No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Glycerin as a Renewable Feedstock for Epichlorohydrin Production. The GTE Process
Abstract
A significant improvement in a process to produce epichlorohydrin through the use of glycerin as renewable feedstock is presented. The glycerin to epichlorohydrin (GTE) process proceeds in two chemical steps. In the first step, glycerin is hydrochlorinated with hydrogen chloride gas at elevated temperature and pressure to a mixture of 1,3-DCH (1,3-dichlorohydrin, 1,3-dichloropropan-2-ol) and 2,3-DCH (2,3-dichlorohydrin, 2,3-dichloropropan-1-ol), using a carboxylic acid catalyst. In the second step, the mixture of dichlorohydrins is converted to epichlorohydrin with a base. This solventless process represents an economically and environmentally advantageous, atom-efficient process to an existing commodity chemical that can employ a renewable resource for its primary feedstock.
... Currently, chiral ECH is industrially obtained using a two-step chemical approach including the saponification of 1,3-dicholoro-2-propanol (1,3-DCP) to prepare racemic ECH and the subsequent kinetic resolution route to get optical pure ECH. The approach was developed and widely employed for decades (Bell et al. 2008;Santacesaria et al. 2010). However, the low yield (42-44%), high-salt wastewater as well as the high production cost have limited the green production of chiral ECH (Bell et al. 2008;Santacesaria et al. 2010;Zou et al. 2018). ...
... The approach was developed and widely employed for decades (Bell et al. 2008;Santacesaria et al. 2010). However, the low yield (42-44%), high-salt wastewater as well as the high production cost have limited the green production of chiral ECH (Bell et al. 2008;Santacesaria et al. 2010;Zou et al. 2018). Asymmetric biosynthesis of chiral ECH from 1.3-DCP has come into sight of scientists and engineers with the significant advantages such as high theoretical yield, low catalyst cost, mild reaction conditions, environmental friendliness etc. (Xue et al. 2015a). ...
Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM⁻¹ s⁻¹), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM⁻¹ s⁻¹. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides.
... The conventional method for the production of epichlorohydrin (C3H5ClO) uses energy-intensive multistep processes involving the addition of chlorine to propene (C3H6) at high temperatures to give allyl chloride (C3H5Cl) and, subsequently, reacting the product with hypochlorous acid (HOCl) to form two dichlorohydrins isomers. Finally, dichlorohydrins are reacted with sodium hydroxide (NaOH) to yield epichlorohydrin (C3H5ClO) [89,90]. In addition to the high energy requirements, this method has major drawbacks, including the application of hazardous chlorine, low atom efficiency of the chlorine and a large number of by-products for disposal [91]. ...
... The conventional method for the production of epichlorohydrin (C 3 H 5 ClO) uses energy-intensive multistep processes involving the addition of chlorine to propene (C 3 H 6 ) at high temperatures to give allyl chloride (C 3 H 5 Cl) and, subsequently, reacting the product with hypochlorous acid (HOCl) to form two dichlorohydrins isomers. Finally, dichlorohydrins are reacted with sodium hydroxide (NaOH) to yield epichlorohydrin (C 3 H 5 ClO) [89,90]. In addition to the high energy requirements, this method has major drawbacks, including the application of hazardous chlorine, low atom efficiency of the chlorine and a large number of by-products for disposal [91]. ...
The chemical industry is considered to be one of the largest consumers of energy in the manufacturing sector. As the cost of energy is rising rapidly, coupled with the increasingly stringent standards for the release of harmful chemicals and gases into the environment, more attention is now focused on developing energy efficient chemical processes that could significantly reduce both operational costs and greenhouse gas emissions. Alkene epoxidation is an important chemical process as the resultant epoxides are highly reactive compounds that are used as platform chemicals for the production of commercially important products for flavours, fragrances, paints and pharmaceuticals. A number of epoxidation methods have been developed over the past decade with the ultimate aim of minimising waste generation and energy consumption. In this review paper, some of the recent advances in epoxides synthesis using energy efficient processes are discussed. The epoxidation methods may provide sustainability in terms of environmental impact and energy consumption.
... Epichlorohydrin (ECH) is produced by two industrial processes: the glycerin route and the propene route via allyl chloride [61]. Here, the dominant commercial propene route is analysed [61]. ...
... Epichlorohydrin (ECH) is produced by two industrial processes: the glycerin route and the propene route via allyl chloride [61]. Here, the dominant commercial propene route is analysed [61]. The process has conventionally three steps [33]: ...
Renewable sources of energy supply an increasing share to the electricity mix although they show much more fluctuations than conventional energy sources. Hence, net stability and availability represent very large challenges. Demand response can positively contribute to the solution of this issue as large electricity consumers adapt their consumption to the available electricity. In the past, chloralkali electrolysis has been suggested as such a large consumer. Unfortunately, its main product, chlorine, cannot be easily stored in large amounts, so that downstream processes have to operate based on a fluctuating feed. This work reviews the processes within the chlorine value chain, determines the most promising ones for flexibilisation based on their chlorine consumption, and analyses these processes in more detail to assign them to one of four flexibility categories. It is shown that 45% of the theoretical potential could be used for demand response right away.
... Currently, traditional production methods of ECH, such as high-temperature chlorination of propylene and glycerol chlorination, are gradually being banned due to severe environmental pollution. 5,6 Direct epoxidation of allyl chloride (ALC) is the most promising green synthesis technology for producing ECH. 7,8 Compared to traditional methods for preparing ECH, it has the advantages of low energy consumption, low waste treatment investment and environmental friendliness. ...
BACKGROUND
The direct epoxidation of allyl chloride is a clean and efficient synthesis method for producing epichlorohydrin (ECH), which is a crucial organic intermediate widely used in the fields of renewable energy and aerospace. However, the presence of multiple azeotropes in the synthesized product using this method complicates the separation process and results in high energy consumption. To efficiently separate high‐purity ECH, this paper investigates and analyzes three separation schemes based on phase‐equilibrium analysis: hybrid extractive distillation (HED), pressure swing distillation (PSD) and three‐column batch distillation (TCBD).
RESULTS
The operating parameters of the three separation processes are optimized by the sequential iterative optimization method such that the minimum total annual cost can reach $493 491 yr⁻¹. The thermal integration method is used for process energy‐saving optimization, and the total annual cost can be further reduced by 6.9%. In addition, a comprehensive evaluation based on economic, energy, environmental and exergy analysis is conducted, and reveals that the TCBD process with thermal integration is optimal. A control structure is designed for the TCBD process to enhance its robustness such that the purity of ECH remains above 99.9 mol% under ±10% disturbances in feed flowrate and composition.
CONCLUSIONS
Compared with the HED and PSD processes, the TCBD process has better economic and environmental benefits, and its control structure can effectively resist disturbances. It is reasonable to believe that the TCBD process can be an excellent solution for the industrial production of ECH. © 2024 Society of Chemical Industry (SCI).
... It is also used in the commercial manufacture of epichlorohydrin. Epichlorohydrin is produced in a similar manner by Solvay and Dow Chemical Company [43]. When the principal hydroxyl groups in glycerol are selectively oxidised, the economically valuable chemicals glyceraldehyde [44], glyceric acid [45] and tartronic acid [46] are formed. ...
Globally, there is a climate change due to greenhouse gases, hence the production processes for chemicals should comply with green chemistry principles to decrease the impact it has on the climate. This book chapter focuses on the catalytic production of glycerol, which is a platform chemical that is widely used in the manufacture of various industrially important chemicals and derivatives, namely 2,3-dihydroxypropanal, glycerol ether, glycerol ester, acrolein, 1,2-propanediol and glycidol. The literature reviewed compares the production of glycerol using homogeneous and heterogeneous catalysts, to determine efficient and environmentally benign glycerol catalysts and to study glycerol as a platform chemical and its value in application.
... 8,9 In this route, glycerin is directly converted to 1,3-DCP by chlorination (also with a small part of 1,2-DCP), leading to the significant improvement of chlorine atom economy. 10 Consequently, in the increasingly popular glycerin route, the dehydrochlorination process of 1,3-DCP is an essential step to obtain EPCH. 11 Hence, the kinetics of this reaction has been highly concerned by researchers. ...
Dehydrochlorination of 1,3‐dichloropropanol with alkali is a key step to industrially produce epichlorohydrin. But there are many side reactions involved in the synthesis process. In this work, a complete mechanism and kinetics investigation of the related reaction network was constructed. Density functional theory simulation method was first used to simulate the possible reactions so as to confirm the reaction mechanism and simplify the reaction network. Based on the simulation results, the complex reaction network was simplified into a three‐step consecutive reaction. The kinetic parameters of the three consecutive steps, including the order of the reaction, the pre‐exponential factor, and activation energy, were experimentally determined by conductance and other methods. All the experimental results are basically consistent with the simulation. The obtained kinetics data provide a basis for epichlorohydrin synthesis process optimization.
... Epichlorohydrin (ECH), a colorless, volatile oily liquid, one of the most crucial organic synthetic intermediates, is applied extensively in the industrial manufacture from production of epoxide resins, chlorohydrin rubbers [1][2][3][4], several pharmaceutical products, CO2 reutilization to functionalization material [5][6][7][8][9]. There have been several industrial synthesis approaches recorded for the manufacture of ECH from propylene chlorination [10][11][12], glycerol chlorination [13], to propylene acetate hydrolysis. Among these routes, the chlorination of propylene under high temperature is more widely used, deriving benefit from its lower fixed-asset investment and abundant raw material storage. ...
Mass production of Epichlorohydrin (ECH) via epoxidizing allyl chloride suffers from determining the optimal reaction parameters and reproducibility. Titanium silicalite-1 (TS-1) catalyst has been successfully employed to reduce activation energy, but many reaction conditions are involved in the process. To optimize ECH production by analysing its yields, Taguchi method was implemented for reducing time and cost. Included in the reaction parameters were reaction temperature, reaction time and the reactant ratio. This study investigated preparation of heterogeneous catalysts using hydrothermal method and their characterization by XRD, IR, SEM and TEM, which confirmed the presence of ordered MFI structure. Plots of S/N suggested that reaction time was the most influential factor, followed by reaction time in ECH production. The optimum factor parameters were acquired as follows, a reaction time of 40 min, reaction temperature of 90 oC and the molar ratio of H2O2: allyl chloride equal to 1. Aimed at the final confirmation, ECH production experiment was also practiced. Established on the obtained results, the yield of ECH was hugely upgraded to the value of 83.13and#177;1.03 % with only ~0.7% deviated from predicted value.
... 41 Glycerin is a waste product of bio-diesel production and can be transformed into epichlorohydrin. 42 Despite its high toxicity and mutagenicity, several reports of its alternating copolymer with CO2 exist. 43 1,2-epoxy-4-cyclohexene (CHDO) is promoted as a sustainable alternative to CHO. ...
Here a successful synthesis of a fully biobased polycarbonate starting from menthol was established. Therefore, an upscalable route for the synthesis of menthene oxide was installed. Direct elimination of the hydroxyl moiety of menthol was not possible; thus, a tosylation and subsequent elimination had to be performed. Epoxidation using mCPBA resulted in the necessary monomer for the polymerization. Two catalytic systems were tested for the copolymerization of MenO and CO2. The first was a β-diketiminate complex of zinc. A controlled reaction was possible and the polycarbonate PMenC was obtained without ether defects. However, the reaction lacked sufficient monomer conversion, limiting its molecular weight to an Mp of 44400. Thermal properties exceeded that of PLimC and PCHC. Its Tg of 145 °C and T5% of 308 °C were both extraordinarily high and provided a reasonable processing window of over 160 °C for potential melt processing applications. Hydrolysis of the polymer showed a stereoselectivity towards a single configuration at the cyclohexane ring. The second catalytic system relied on the combination of the Lewis acid TEB and an initiating Lewis base. Here a full screening of the reaction parameters was performed to establish a metal-free route for the synthesis of PMenC. Conversions up to 70% were achieved, but molecular weight could not be raised above an Mn of 28500. 1H-NMR spectroscopy revealed differences in the polymers obtained with the zinc catalyst depending on the reaction temperature. Hydrolysis identified these differences as the incorporation of the two different diastereomers at the cyclohexane ring. Furthermore, terpolymers of MenO and CO2 with BO or undecene oxide were synthesized to increase chain mobility. Although the reaction was successful and the Tg could be varied from 6 °C to 165 °C, it was only possible to prepare films with polymers, which contained a high content of PBC. After crosslinking with a bifunctional UV-crosslinker, these films were even stable at temperatures above room temperature. These terpolymers were then electrospun to fibers in the nanometer scale. The formation of beads, which occurred upon the addition of the crosslinker, could be suppressed by the use of a solvent mixture with methanol as a non-solvent. Yarns and fiber mats were obtained, which were applied as air filtration membrane or for the separation of water and apolar solvents.
... ab-DCP and ac-DCP, meanwhile, are produced in two ways, from allyl chloride leaving mixtures with a higher concentration of ab-DCP which is not very efficient due to its low reactivity compared with ac-DCP to produce epichlorohydrin (Bell et al., 2008;de Araujo Filho et al., 2013;Luo et al., 2009;Wang et al., 2007). ...
A homogeneously catalyzed gas-liquid process, glycerol hydrochlorination was studied in a semibatch reactor with gaseous hydrogen chloride (HCl) as a continuous phase and acetic acid as homogeneous catalyst. Several experiments were conducted varying the temperature in the jacket of the reactor in the range 70-115 °C and the catalyst mole fraction between 0-15 mol-%. The effects of HCl on the kinetics was investigated by changing the partial pressure of HCl in the range 0.25-1 atm by diluting HCl with inert gas, while the absolute pressure of the reactor was remained constant at atmospheric pressure. The experiments revealed new information about this particular reaction system. Considerable changes in the reactor temperature occurs, temperature changes close to 20 °C, which are an effect of the absorption process of gaseous HCl. The HCl uptake in the liquid phase exhibits a strange behavior at the beginning of the reaction, associated to the appearance of water and the temperature change during the experiments. The experiments also revealed that a part of the catalyst is transformed into esters in the presence of glycerol and 3-chloro-1,2-propanediol (α-MCP), particularly at high catalyst concentrations. These esters were detected and an improved gas-chromatographic method was developed to analyze these quantitatively. In long run, the the esters are converted back to the original catalyst, acetic acid, as the reaction stops because of lack of glycerol. The information provided by the experiments in this work gives better understanding of the reaction mechanism and thus they are the basis for a rational design of glycerol hydrochlorination reactors.
... Epichlorohydrin is a high-volume commodity chemical used in the production of epoxy resins, synthetic elastomers, and sizing agents for the papermaking industry, and also, a for polymers, [89] the epichlorohydrin manufacture, from propylene and chlorine as primary raw materials in a multi-step process. [90]. ...
Glycerol is now used in a large variety of applications because the unique structure, and renewability feature, and chemical and physical properties, and because it is physiologically innocuous.
The use of glycerol for advanced organic syntheses and the conversion of glycerol into value-added chemicals is now emerging as a fascinating challenge. such as Oxidation, Esterification, Chlorination, Dehydration, Hydrogenolysis, Polymerization, Etherification, glycerol is nowadays considered one of the most relevant platform chemicals.
... The bio-based carbon content (BCC) of the developed materials was determined on the basis of the study of Pan et al., 67 where in the first step was calculated the carbon percentage for each compound and then the bio-based carbon content for all formulations. Both epoxy monomers are compounds synthetized by glycidylation 26−28,68 of phloroglucinol and vanillyl alcohol, renewable compounds, with biobased epichlorohydrin (produced from glycerine as renewable feedstock 69 ), so they are 100% bio-based, while HMPA and MNA are for the moment 100% petrochemical-based compounds. The BCC by weight of the designed thermoset resins was calculated using ...
... On the other hand, ECH is usually synthesized from allyl chloride, which is obtained by the reaction between chlorine and propylene, a petro-sourced reagent [75]. However, ECH can be produced from bio-based glycerol (Fig. 7) [76,77]. An example of a commercial biobased ECH is Epicerol® marketed by the Solvay group. ...
Cationic photopolymerization is among the greenest processes used to obtain polymers since light is abundant, inexpensive and allows for rapid and waste-less curing at room temperature. Moreover, in the current search for the reduction of the environmental impacts of polymers, the use of biobased monomers is one of the most crucial stakes. At the crossroads of these domains, biobased monomers photopolymerization offers the best of both. Hence, this review aims at underlying the increasing importance of cationic photopolymerization in combination with bio-based photopolymerizable monomers, and describes the numerous reactive species derived from bioresources that can lead to innovative materials through cationic photopolymerization reactions. This review intends to be a guide to orient academic teams and industries involved in reducing both environmental impacts and toxicity towards the synthesis of environmentally safe materials. The recent advances on the photochemical systems used, the toxicity of the cationic photoinitiating systems, the reactivity of the new epoxy bio-sourced monomers, their thermomechanical properties as well as the applications of the targeted materials will be described.
... Epichlorohydrin can be produced using glycerol from renewable feedstock. The glycerol-to-epichlorohydrin (GTE) is a process based on two chemical steps: (1) hydrochlorination of glycerin with hydrogen chloride gas at elevated temperature and pressure, using a carboxylic acid as catalyst, (2) conversion of the dichlorohydrin formed in the first step to epichlorohydrin with a base [135]. This new GTE process can reduce energy consumption by about one-third, generate less than 1/10th of the waste water and produces less chlorinated organics, when compared to conventional processes [136,137]. ...
Thermosets from renewable sources have been the research focus of last few decades. Biobased thermoset resins are considered important candidates for sustainable development since they present the potential to reduce both CO2 footprint and the dependency on petroleum. In order to reduce the ecological impact of plastic without compromising mechanical and thermal behavior, in some cases, partially biobased raw materials are accepted. High biocontent resins based on low toxicity raw materials are the goal for the future biobased thermoset polymers. Free-formaldehyde biobased phenol resins and free-bisphenol-A epoxy resins are some examples of this green chemistry concept. The importance of the conversion of biomass into sustainable biobased polymers will be discussed. Chemical pathways developed to make monomers for thermoset polymers from vegetable oils, carbohydrates, lignocelluloses, algae, and even plastic waste will be reviewed. Application and commercialized production of the biobased thermoset polymers will also be highlighted.
... However, another oil-based substance, epichlorohydrin (ECH) remains an important precursor in manufacturing glycerol glycidyl ether (GGE), which is monomer for the synthesis of polyGGE via cationic ring-opening polymerization [10][11][12]. Although bio-based glycerol can be used as a renewable feedstock for ECH production [13,14], ECH residues and its organochloride derivatives are still toxic to cells and may limit the cell and tissue compatibility as well as biomedical applications of glycerol-based epoxy networks [15]. ...
Glycerol-based epoxy networks have great potential for surface functionalization, providing anti-microbial and protein repellant function. However, the synthesis of glycerol glycidyl ether (GGE) monomer often requires excessive epichlorohydrin (ECH). ECH derived organochloride containing byproducts from monomer production maybe present in the eluent of the polymer networks prepared by cationic ring-opening polymerization. Here, the cytotoxicity analysis revealed cell damages in contact with the polyGGE eluent. The occurrence of organochlorides, which was predicted based on the data from high-performance liquid chromatography/electrospray ionization mass spectrometry, as confirmed by a constant chloride level in GGE and polyGGE, and by a specific peak of C–Cl in infrared spectra of GGE. The resulting polyGGE was densely crosslinked, which possibly contribute to the trapping of organochlorides. These results provide a valuable information for exploring the toxins leaching from polyGGE and propose a feasible strategy for minimizing the cytotoxicity via reducing their crosslink density.
Graphic abstract
The eluent of poly(glycerol glycidyl ether) (polyGGE) films impaired the viability and metabolic activity of L-929 cells due to the organochloride byproducts or epichlorohydrin precursors originating from the GGE monomer, which was predicted based on the data from high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC–ESI–MS) and confirmed by chloride content analysis and attenuated total reflection fourier transform infrared (ATR-FT-IR) spectroscopy.
... Many microorganisms were able to metabolize glycerol aerobically and anaerobically but none of them were used at industrial scale [29]. ...
Glycerol is a valuable by-product in the biodiesel industries. However, the increase in biodiesel production resulted in an excess production of glycerol, with a limited market compared to its availability. Precisely because glycerol became a waste to be disposed of, the costs of biodiesel production have reduced. From an environmental point of view, identifying reactions that can convert glycerol into new products that can be reused in different applications has become a real necessity. According to the unique structural characteristics of glycerol, transformation processes can lead to different chemical functionalities through redox reactions, dehydration, esterification, and etherification, with the formation of products that can be applied both at the finest chemical level and to bulk chemistry.
... The reaction will then produce a mixture composed of 1,3dichlorohydrin, 1,3-dichloropropan-2-ol, 2,3-dichlorohydrin, and 2,3-dichloropropoan-1-ol. The second step consists of converting the dichlorohydrin mixture into epichlorohydrin using NaOH [129,141,163]. Simola and Iosco [164] developed a process aiming at a continuous production of epichlorohydrin in the presence of an alkaline solution. ...
Glycerol is a common by‐product of industrial biodiesel syntheses. Due to its properties, availability, and versatility, residual glycerol can be used as raw material in the production of high value‐added industrial inputs and outputs. In particular, products like hydrogen, propylene glycol, acrolein, epichlorohydrin, dioxalane and dioxane, glycerol carbonate, n‐butanol, citric acid, ethanol, butanol, propionic acid, (mono‐, di‐ and triacylglycerols), cynamoil esters, glycerol acetate, benzoic acid, and other applications. In this context, the present study presents a critical evaluation of the innovative technologies based on the use of residual glycerol in different industries, including the pharmaceutical, textile, food, cosmetic, and energy sectors. Chemical and biochemical catalysts in the transformation of residual glycerol are explored, along with the factors to be considered regarding the choice of catalyst route used in the conversion process, aiming at improving the production of these industrial products. This article is protected by copyright. All rights reserved
... Carboxylic acids have been used as catalysts in the chlorination of glycerol [31]. Briggs and coworkers and Yin and coworkers separately revealed that the catalytic efficiency of carboxylic acids is influenced by their steric hindrance [32,33] rather than their pKa [33]. Less hindered carboxylic acids tended to exert higher catalytic activity. ...
Developments that result in high-yielding, low-cost, safe, scalable, and less-wasteful processes are the most important goals in synthetic organic chemistry. Continuous-flow reactions have garnered much attention due to many advantages over conventional batch reactions that include precise control of short reaction times and temperatures, low risk in handling dangerous compounds, and ease in scaling up synthesis. Combinations of continuous-flow reactions with homogeneous, metal-free catalysts further enhances advantages that include low-cost and ready availability, low toxicity, higher stability in air and water, and increased synthetic efficiency due to the avoidance of the time-consuming removal of toxic metal traces. This review summarizes recently reported continuous-flow reactions using metal-free homogeneous catalysts and classifies them either as acidic catalysts, basic catalysts, or miscellaneous catalysts. In addition, we compare the results between continuous-flow conditions and conventional batch conditions to reveal the advantages of using flow reactions with metal-free homogeneous catalysts.
... The optimal reaction conditions were established using epichlorohydrin (ECH) as substrate and dimethylamino pyridine DMAP as base. Epiclorohydrin was selected as model substrate because is one of the most interesting epoxides that can be produced from glycerin obtained from vegetable oil [32] and DMAP as base due its proved efficiency compared with other bases [12,[33][34][35]. The excellent catalytic activity in presence of this base was firstly reported by Paddok et al. [36] who attributed it to the coordination of DMAP to the metal generating more electron-rich centers in the metal-catalyst. ...
Commercial iron (II) phthalocyanine (FePc) was knitted with biphenyl using a Friedel–Crafts reaction to yield a micro-meso porous organic polymer (FePc-POP) with a specific surface area of 427 m²/g and 5.42% of iron loading. This strategy allowed for the direct synthesis of a heterogeneous catalyst from an iron containing monomer. The catalytic system, formed by the knitted polymer containing FePc and DMAP (4-dimethylamino pyridine) as base, results in an efficient heterogeneous catalyst in the cycloaddition of CO2 to epichlorohydrin to selectively obtain the corresponding cyclic carbonate. Thus, a TON (mmol substrate converted/mmol catalysts used) value of 2700 was reached in 3 h under mild reaction conditions (solvent free, 90 °C, 3 bar of CO2). The catalyst does not exhibit leaching during the reactions, which was attributed to the excellent stability of the metal in the macrocycle.
... Low prices favor the development of new applications for glycerol (e.g., epichlorohydrin) and created new markets, especially in Asia. For example, DowChemical designed a process to produce epichlorohydrin from crude glycerol [GTE (glycerine-to-epichlorohydrin) process] to capitalize on the low crude glycerol price (Bell et al. 2008). Refined glycerol is sometimes perceived as an application of crude glycerol. ...
Rapidly increasing environmental problems and limited fossil resources are motivating the development of sustainable energy options. In terms of this, microbial fuel always fascinated world community, but their implementation has number of hurdles. However, evolvement of metabolic engineering converts these microbes into efficient cell factories for biofuel production. It incorporates the techniques that work in a frame or synchronized manner to modify the existing enzyme and pathway, related to desired product. This chapter gives brief insight into different strategies and techniques conferring metabolic engineering and highlights the challenges on more advanced level.
Konjac glucomannan (KGM) is a non-toxic, biodegradable polysaccharide known for its excellent gel-forming properties and high water retention. This study presents a novel tannin-enhanced KGM hydrogel, tailored for controlled solvent release and improved surface adaptability in artwork cleaning applications. Hydrogel formulation consisting of KGM crosslinked with borax was optimized generating borax through the reaction of boric acid and sodium hydroxide. This resulted in uniformly crosslinked gels with improved tensile strength and high moisture retention, essential for controlled cleaning. Moreover, tannins were incorporated in the optimised KGM-based polymer matrices. This modification was introduced as a novel and sustainable strategy to enhance crosslinking, leveraging natural polyphenols to add functional properties. Two tannins were tested: a condensed tannin isolated from Vitis vinifera, and a hydrolyzable tannin isolated from oak, tannic acid. Tannins were incorporated either through hydrogen bonding or covalently. Covalent attachment was achieved using epichlorohydrin (ECH) to add an epoxide motif to the tannin, enabling covalent binding with KGM. The resulting gels were thoroughly characterized for their chemical, rheological and morphological properties, showing that novel crosslinking via in situ borax formation improved moisture retention and surface adaptability, while the incorporation of tannins enhanced water absorption, maintaining high retention and favorable mechanical properties.
This review critically examines the dual nature of chlorine as both an indispensable base chemical and a potential risk. Chlorine and its byproduct hydrogen chloride play essential roles in the production of pharmaceuticals, plastics, agrochemicals, and disinfectants. However, their inherent toxicity, risks of handling, and environmental impacts necessitate a reassessment of their use and sustainability. The review explores emerging and established chlorine‐free technologies, such as the hydrogen peroxide to propylene oxide process and phosgene‐free routes for polycarbonate production, evaluating their potential to reduce reliance on chlorine. For applications where chlorine remains indispensable, innovations such as trichloride‐ and bichloride‐based ionic liquids provide safer storage and handling options for chlorine and hydrogen chloride, respectively. These ionic liquids not only enhance safety but also support renewable energy integration through their potential as indirect energy storage solutions. While chlorine is unlikely to be fully replaced in the near future, ongoing innovations in chlorine‐free processes and safer technologies may redefine its industrial use, contributing to a more sustainable and secure chemical industry.
Epoxy resins (EPs) are crucial for high‐performance applications like lightweight materials, due to their excellent properties. However, the commonly used diglycidyl ether of bisphenol A (DGEBA) has two major disadvantages: it is synthesized mainly from petrochemicals and includes the health concerning bisphenol A. Eugenol is a bio‐based aromatic compound that can be modified into di‐ or triglycidyl ether. Through investigations four monomers are obtained based on eugenol and crosslinked with two curing agents isophorone diamine and 4,4′‐diaminodiphenyl sulfone to compare the properties of the resulting EPs with references containing DGEBA. Using new synthesis routes, the bio‐content of the monomers can be increased up to 94 wt%. Intramolecular cyclization occurs if a hydroxy group is in ortho‐position to the glycidyl ether group. The crosslinking conditions of the bio‐based monomers are comparable to or lower than those of DGEBA. The eugenol‐based triglycidyl monomers exhibit very high glass transition temperatures of up to 271 °C, almost 50 °C above the reference value, which can enable their use for lightweight construction such as matrices for fiber‐reinforced plastics. The char content of all bio‐based EPs after pyrolysis is significantly higher in comparison to the references, which may have a favorable effect on fire resistance.
Modeling and optimization of real chemical reactors is challenging. A program to systematically compare the performance of an existing reactor with basic reactor models was built. The program was tested on the hydrochlorination of bio‐based glycerol in a bubble column. The model‐based approach provided insights into the reactor's concentration profiles, mass transfer, and mixing. In this case study, a plug‐flow tubular reactor (PFTR) is sufficient as a model for process intensification. Based on the results, a novel reactor design that significantly improves yields was proposed and simulated.
Vanillyl alcohol has emerged as a widely used building block for the development of biobased monomers. More specifically, the cationic (photo‐)polymerization of the respective diglycidyl ether (DGEVA) is known to produce materials of outstanding thermomechanical performance. Generally, chain transfer agents (CTAs) are of interest in cationic resins not only because they lead to more homogeneous polymer networks but also because they strikingly improve the polymerization speed. Herein, the aim is to compare the cationic chain‐growth photopolymerization with the thermally initiated anionic step‐growth polymerization, with and without the addition of CTAs. Indeed, CTAs lead to faster polymerization reactions as well as the formation of more homogeneous networks, especially in the case of the thermal anionic step‐growth polymerization. Resulting from curing above the T G of the respective anionic step‐growth polymer, materials with outstanding tensile toughness (>5 MJ cm ⁻³ ) are obtained that result in the manufacture of potential shape‐memory polymers.
Traditional epoxy resins are made from non‐renewable fossil resources, which are difficult to reprocess and recycle, and their flammability makes them unsafe during use. In this experiment, an epoxy resin containing Schiff base (TA‐VAN‐EP) was synthesized successfully with biomass‐derived raw materials. This new material not only had favorable mechanical properties but also had good flame retardancy and degradation properties. The chemical structure of TA‐VAN‐EP was characterized by Fourier transform infrared (FTIR) spectroscopy and ¹ H nuclear magnetic resonance (NMR) spectroscopy. Its mechanical properties, thermal stability, flame‐retardant properties, and other properties were tested. The results showed that, compared with the pure epoxy resin (EP), the mechanical properties of TA‐VAN‐EP were significantly improved, and the glass transition temperature ( T g ) was increased from 152°C to 190°C. Additionally, TA‐VAN‐EP reached a V‐1 rating during the UL‐94 test, and the limited oxygen index (LOI) value increased from 24.7% to 28.4%. Also, the total heat release (THR), smoke production rate (SPR), and total smoke release (TSR) decreased extremely. Moreover, TA‐VAN‐EP demonstrated good degradation performance under acidic conditions. In conclusion, this work provided a new idea for the production of bio‐based flame‐retardant epoxy resin with promising degradable abilities and mechanical properties.
The synthesis of bio‐derived cyclic carbonates is attracting a lot of attention as the incorporation of bio‐derived functionality into these compounds provides the opportunity to prepare previously unknown structures, whilst also improving their sustainability profiles. This study presents a facile preparation of diastereomerically pure bio‐derived cyclic carbonates displaying a range of optical rotation values. These compounds are obtained from glycidol, amino acids and CO2 in a facile two‐step approach. Initially, the diastereomerically pure amino acid functionalised epoxides are prepared through a robust Steglich esterification of enantiopure glycidol (R or S) and an amino acid (D or L). Thereafter, in a second step, cycloaddition of the epoxide with CO2 results in the retention of the initial stereochemistry of the epoxide, furnishing novel diastereomerically pure and optically active cyclic carbonate products. A DFT study has explained the basis of this observed retention of configuration for these compounds. Further, results from this DFT study also provide new mechanistic information concerning a co‐catalyst‐free cycloaddition reaction starting from glycidol when using the gallium‐catalyst, which is found to operate through metal‐ligand cooperativity.
In the present study, an epoxy compound, 1,2-epoxy-6-methyl-triglycidyl-3,4,5-cyclohexanetricarboxylate (EGCHC) synthesized from sorbic acid, maleic anhydride, and allyl alcohol is proposed. Using commodity chemicals, a bio-based carbon content of 68.4 % for the EGCHC resin is achieved. When cured with amine hardeners, the high oxirane content of EGCHC forms stiff cross-linked networks with strong mechanical and thermal properties. The characterization of the epoxy specimens showed that EGCHC can compete with conventional epoxy resins such as DGEBA. A maximum stiffness of 3965 MPa, tensile strength of 76 MPa, and T g of 130°C can be obtained by curing EGCHC with isophorone diamine (IPD). The cured resin showed to be decomposable under mild conditions due to the ester bonds. The solid material properties of EGCHC expose its potential as a promising bisphenol A, and epichlorohydrine free alternative to conventional petroleum-based epoxies with an overall high bio-based carbon content.
The development of efficient catalysts that include the advantages of homogeneous and heterogeneous catalysts is a challenge that can be achieved with metal-organic frameworks (MOFs) since they can incorporate different functionalities in their structure that make them promising catalysts for different processes. Herein, two new isoreticular nitrogen-rich naphthalene cobalt-MOFs, Co-NDTz and Co-NDPhTz, were successfully prepared under solvothermal conditions from the corresponding linkers (H2NDTz=2,6-naphthaleneditetrazole and H2NDPhTz=2,6-bis(4-(1H-tetrazol-5-yl)phenyl)naphthalene). These Co-tetrazole-based MOFs combine Lewis acid and redox functionalities and good CO2 adsorption and after being thermally activated resulted to be excellent efficient catalysts for the epoxidation of alkenes and CO2 cycloaddition to epoxides yielding cyclic carbonates, reaching turnover numbers up to 2500. Furthermore, these two reactions take place following a highly desired one-pot tandem process and a cyclic carbonate was obtained from styrene and CO2 under solvent-free conditions. In addition, the heterogeneous catalysts are easily recycled without noticeable loss of catalytic activity and without important structural deterioration.
The synthesis of bio-based functional molecules and their further conversion to value-added products are among the most investigated research fields within the green chemistry community. In this work, we review the preparation of bio-based glycidol and its use as starting material for other chemicals. Herein, we discuss the catalytic approach for the synthesis of several classes of glycidol-derived organics characterized by relevant industrial applications. In detail, glycidol conversion to 1,2 and 1,3-propanediol, glycerol carbonate, solketal, monoalkyl glyceryl ethers, and polymers is reported and future perspectives in this context are proposed.
Endocrine disrupting compounds (EDCs) are one of the many classes of harmful pollutants frequently found in water resources. Even at low concentrations, EDCs might accumulate in the organisms and interfere on numerous processes controlled by hormones. Parabens, for example, are preservatives widely used in pharmaceutical and cosmetic industries, but several studies related them to human breast cancer. It is well-known that electrochemical technologies are an efficient alternative for wastewater treatment, promoting the appropriate destruction of EDCs. However, most studies are applied to single target contaminant solutions, which may neglect the impact from co-exited inorganic/organic pollutants. Based on that, this study aimed to elucidate the interfering effects of two target organic contaminants of very different nature during electrochemical mediated process. For that, methyl paraben (MeP) and propylene glycol (PG) were selected as models of aromatic/phenolic and carboxylate compounds versus low-molecular aliphatic alcohols. These two compounds are often together used in preservative blends and cosmetic/pharmaceutical formulations. PG is not a harmful chemical, but it is present in several types of effluents in relatively high concentrations. Thus, it may interfere on the degradation of numerous pollutants of low concentrations. The electrochemical treatment of a mixture containing 100 mg L-1 MeP +1000 mg L-1 PG showed that both contaminants suffered interfering effects. The presence of MeP negatively interfered on PG degradation; the carboxylate compound is more easily oxidized even at lower molecular concentration. On the other hand, the presence of PG showed an unexpected positive effect on MeP degradation, that was not reflected on its mineralization. The results indicate that in addition to the expected effect of anodic competition, polymerization and copolymerization reactions may also occur in the studied system. The use of an acidic buffer medium increased the removal of both contaminants and favored the oxidation pathway over the polymerization. In this case, the increase in the removal was reflected in the mineralization process, which increased up to 6 times when the mixture was treated in the buffered medium.
The paper describes the properties of glycerol produced by transesterification, especially the ester content in the glycerol phase (ester losses) including the distribution of esters according to higher fatty acids. Glycerol, produced by transesterification of oil as a side product – the polar glycerol phase, is an important chemical raw material. The decreasing of ester losses is important because it (i) increases the ester yield and especially (ii) decreases the cost of glycerol purification. The transesterification of oils (rapeseed, olive, palm, sunflower and Camelina Sativa) with various distributions of fatty acids was carried out by methanol, ethanol and butanol including different transesterification stopping. The losses of ethyl and butyl esters are much higher than losses of methyl ester (approximately 2-3x). The distribution of ethyl and butyl esters in the glycerol phase is the same as in the ester phase, whereas distribution of methyl ester is different and depends on the way of transesterification stopping. The reason is the different polarity of methyl esters, which depends on the type of fatty acid. The polarity increases with increasing of double bonds, i.e. the most soluble is methyl ester of linolenic acid in the glycerol phase.
In the paper industry, polyaminopolyamide-epichlorohydrin (PAE) resins are the principal commercial products, introduced in the 1950s, used to manufacture wet-strengthened paper, that is paper that holds it strength despite being wet. Nowadays, these wet-strengthened products are used in liquid packaging board (for milk and juice and other beverage carriers), tea bag and coffee filter paper, paper towels, and specialty grades such as currency paper.
Cumulative plastic production worldwide skyrocketed from about 2 million tonnes in 1950 to 8.3 billion tonnes in 2015, with 6.3 billion tonnes (76%) ending up as waste. Of that waste, 79% is either in landfills or the environment. The purpose of the review is to establish the current global status quo in the plastics industry and assess the sustainability of some bio-based biodegradable plastics. This integrative and consolidated review thus builds on previous studies that have focused either on one or a few of the aspects considered in this paper. Three broad items to strongly consider are: Biodegradable plastics and other alternatives are not always environmentally superior to fossil-based plastics; less investment has been made in plastic waste management than in plastics production; and there is no single solution to plastic waste management. Some strategies to push for include: increasing recycling rates, reclaiming plastic waste from the environment, and bans or using alternatives, which can lessen the negative impacts of fossil-based plastics. However, each one has its own challenges, and country-specific scientific evidence is necessary to justify any suggested solutions. In conclusion, governments from all countries and stakeholders should work to strengthen waste management infrastructure in low- and middle-income countries while extended producer responsibility (EPR) and deposit refund schemes (DPRs) are important add-ons to consider in plastic waste management, as they have been found to be effective in Australia, France, Germany, and Ecuador.
A series of hydroxy‐functionalized phosphonium salts were studied as bifunctional catalysts for the conversion of CO2 with epoxides under mild and solvent‐free conditions. The reaction in the presence of a phenol‐based phosphonium iodide proceeded via a first order rection kinetic with respect to the substrate. Notably, in contrast to the aliphatic analogue, the phenol‐based catalyst showed no product inhibition. The temperature dependence of the reaction rate was investigated, and the activation energy for the model reaction was determined from an Arrhenius‐plot (Ea=39.6 kJ mol⁻¹). The substrate scope was also evaluated. Under the optimized reaction conditions, 20 terminal epoxides were converted at room temperature to the corresponding cyclic carbonates, which were isolated in yields up to 99 %. The reaction is easily scalable and was performed on a scale up to 50 g substrate. Moreover, this method was applied in the synthesis of the antitussive agent dropropizine starting from epichlorohydrin and phenylpiperazine. Furthermore, DFT calculations were performed to rationalize the mechanism and the high efficiency of the phenol‐based phosphonium iodide catalyst. The calculation confirmed the activation of the epoxide via hydrogen bonding for the iodide salt, which facilitates the ring‐opening step. Notably, the effective Gibbs energy barrier regarding this step is 97 kJ mol⁻¹ for the bromide and 72 kJ mol⁻¹ for the iodide salt, which explains the difference in activity.
As one of the main plastic resin types, polycarbonate-based plastics play an important role in manufacturing and wide applications. However, with increasing awareness of environmental challenges related to petroleum-based polycarbonates, demand for production of bio-based polycarbonates from carbon dioxide (CO2) and renewable feedstocks has attracted significant attention in view of green chemistry and sustainable development. This present review highlights recent advances in the efficient conversion of CO2 and bio-based feedstocks to value-added bio-based polycarbonates with attractive properties. Specifically, an emphasis has been put to renewable bio-based feedstocks that provide bio-based epoxides with long chains, resulting in “soft” bio-polycarbonate materials via innovative and efficient synthetic pathways. These bio-based feedstocks, including plant oils, industrial byproducts (crude glycerol) and pure fatty acids as the comparison, trigger new platform to fully take advantage of CO2 and agricultural or industrial byproducts to bio-degradable polycarbonate plastics. But, some challenges regarding comparable mechanical properties and scale-up do exist. A comprehensive overview of epoxide properties, synthetic mechanism, and state of the art of bio-based polycarbonates from designed bio-based feedstocks are discussed in details. Additionally, an outlook of further engineering consideration has been touched providing insights and forecasts for developing value-added bio-products from CO2 and bio-based feedstocks.
A new reaction mechanism for the glycerol chlorination is proposed. This mechanism is based on theoretical calculations within density functional theory combined with polarizable continuum model . Two possibilities were investigated, the first is the SN2 chlorination forming mono‐ and dichlorinated products and the second one is through an ester intermediate formed by glycerol esterification in the presence of acetic acid as catalyst. Our results indicate that the first chlorination reaction can occur in the absence of the catalyst and the main product is 3‐monochloropropane‐1,2‐diol (1‐MCP). The inhibitory role of water in the second chlorination is also revealed, that is, water formation suppresses the second chlorination when reaction is conducted in the absence of a carboxylic acid. In the presence of the catalyst, oxonium species are formed as reaction intermediates and the main products are 1‐MCP and 1,3‐dichloropropan‐2‐ol (1,3‐DCP). Our results are in agreement with the experimental data, which indicate that the 1,3‐DCP is the main product when an acid catalyst is employed and, also, there is no significant formation of 2‐monochloropropane‐1,2‐diol and 1,2‐dichloropropan‐3‐ol.
Glycerol is a by-product of transesterification, fat splitting, and saponification processes. The rise in biofuels led to excess glycerol and price volatility. Crude glycerol from the biodiesel and the oleochemical industries contains methanol or other impurities, and constitutes a disposal problem. This waste glycerol has invigorated the development of new processes, both chemical and biological, for crude and refined glycerol valorization. Nature has evolved sophisticated microbial pathways for glycerol uptake and dissimilation. The advancement of genetic engineering has allowed us to capitalize on this opportunity and developed microbial production hosts to manufacture a wide array of value-added chemicals from glycerol, ranging from bulk to fine chemicals. Although there are technical challenges associated with microbial glycerol utilization (feedstock composition, substrate and product inhibition, downstream processing, and process economics, to name a few), strain engineering and bioprocess optimization have empowered us to address some, if not all, of these issues. Therefore, the future for utilizing glycerol as a renewable raw material for biomanufacturing holds great promises. This book chapter seeks to consolidate the advances made in the sector of biological glycerol use, by putting equal weight on our discussions of feedstock (i.e., glycerol) and of microbial cell factory.
Alkylation and Hydrogenation Products of BenzeneOxidation and Secondary Products of BenzeneOther Benzene Derivatives
Although glycerol has been a well-known renewable chemical for centuries, its commercial relevance has increased considerably in the last few years because of its rising inevitable formation as a by-product of biodiesel production. The present review gives a broad overview on the chemistry of glycerol starting from the classic esters and oligomers to new products like glycerol carbonate, telomers, branched alkyl ethers, propanediols and epoxides. In particular, the novel possibilities to control the numerous addition, reduction and oxidation reactions via heterogeneous, homogeneous and biocatalysis will be presented. A benchmark will be given to determine the products which will have the best chances of entering the market and which processes are currently most developed.
A new steric substituent constant, Ωs, was proposed in order to evaluate the kinetic steric effect. Ωs is isotropic and dependent most significantly on the number of β-carbon atoms. The rates of several reactions were shown to be correlated with Ωs better than with Es.
It has been recently demonstrated by Mcllwain, Fildes, Gladstone and Knight1 that glutamine is an essential growth factor for most strains of luemolytic streptocci freshly isolated from pathological processes. By the use of glutamine, these investigators have been able to replace completely the hitherto essential meat extractives in their culture medium.
The present work was directed toward elucidation of the mechanism of the substitution reaction which introduces the first of the two halogen atoms in the stereospecific conversion of diacetates to dibromides with fuming hydrobromic acid. To isolate the first replacement reaction for inspection, fuming hydrochloric instead of hydrobromic acid was employed. The cis- and trans-1,2-cyclohexanediols and their acetates, as well as ethylene glycol, were treated with the hydrochloric acid reagent. Chlorocyclohexanol or its acetate was not formed from trans-1,2-cyclohexanediol or its diacetate. On the other hand, chlorocyclohexanol or its acetate, exclusively trans, was obtained from either cis-1,2-diacetoxycyclohexane or the cis-glycol to which some acetic acid was added. No chlorohydrin was obtained from cis-glycol in the absence of the acetic acid catalyst. Analogously, ethylene chlorohydrin was obtained from ethylene glycol in the presence of, but not in the absence of added acetic acid. The suggested mechanism for the introduction of the halogen atom involves the reaction of the glycol monoacetate in the tautomeric ortho-monoacetate form. The latter ionizes to the olefin acetoxonium ion, which occasionally reacts with chloride ion to yield acetoxy-chloride. This mechanism, involving "front-side participation" of an acetoxy group, explains: (i) the catalytic effect of acetic acid; (ii) the successful reaction of the cis-glycol derivative contrasted with the failure of the trans; (iii) the stereochemical result of clean-cut inversion of configuration in the conversion of diacetate or glycol to chlorohydrin.
The reactions involved in epichlorohydrin industrial production have been studied. The reactions can be divided into two groups: ring closure (dehydrochlorination) and ring opening (epoxide hydrolysis). Two analytical techniques, potentiometry and gas chromatography, have been employed in order to follow the time evolution of the reagents. The kinetic parameters of the reactions have been determined and a kinetic model of the overall system is offered.
Methyl methacrylate can be derived from Methacrylic acid. Alternative methods of producing the ester rely on acetone cyanohydrin poduced from acetone and hydrogen cyanide. The cyanohydrine is then treated with H2SO4 and eventualy leads to the desired product with an NH4HSO4 side product.,
There is considerable interest in alternative routes to methacrylic acid that avoid the cyanohydrin route but presently these are not economical.
,
This particular use of CO2 is of great interest, as the materials obtained may have a long life, on the order of several decades. This
property differentiates polymers from monomeric compounds,
which are quickly converted back to CO2 after use. Therefore,
the development of routes to new polymeric materials based on
CO2 is relevant to the storage of CO2.
An oxygen atom on every carbon--this is the problem! While nature provides linear C(3) to C(6) building blocks in the form of sugar alcohols in large and renewable abundance, they are overfunctionalized for the purpose of most chemical applications. Selective deoxygenation by anthropogenic catalyst systems may be one answer to this challenge.
- G P Gibson
G. P. Gibson, Chem. Ind. 1931, 20, 949 -975.
- J B Conant
- O R Quayle
J. B. Conant, O. R. Quayle, Org. Synth., 1941, CV1, 292 -297.
- A Behr
A. Behr et al., Green Chem. 2008, 10 (1), 13 -30.
- T Komatsuzaki
- I Akai
- K Sakakibara
- M Hirota
T. Komatsuzaki, I. Akai, K. Sakakibara, M. Hirota, Tetrahedron 1992 48
(9), 1539.
- S Carra
- E Santacesaria
- M Morbidelli
- P Schwarz
- C Divo
S. Carra, E. Santacesaria, M. Morbidelli, P. Schwarz, C. Divo, Ind. Eng.
Chem. Proc. Des. Dev. 1979, 18 (3), 424 -427.