Miguel ZanuttiniUniversidad Nacional del Litoral | UNL · Faculty of Chemical Engineering FIQ
Miguel Zanuttini
Doctoral
About
71
Publications
11,403
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673
Citations
Citations since 2017
Introduction
Pulping - Cellulosic products - Bio-based Materials - Hemicelulose - Xylan - Cellulose nano fibers (CNF) - Paper properties -
Statistics in Quality Control
Additional affiliations
March 2010 - present
Position
- Professor (Full)
Description
- Imprementation of Statistic in Industrial Quality Control.
May 1992 - present
March 1990 - present
Position
- Professor (Full)
Description
- Institute of Cellulose Technology. Biorefinery - Pulping - Papermaking
Education
March 1982 - April 1986
Publications
Publications (71)
The effect of different ethanol concentrations (0; 3; 9; 12 and 16 wt%) on the degree of ionization of xylan and chitosan, the characteristics of polyelectrolyte complex (PEC) suspensions, and the derived films, were exhaustively analyzed through several analytical techniques. Results indicate that the degree of ionization of both polyelectrolytes...
A novel procedure based on the addition of polyelectrolyte complexes (PECs) onto the pulp containing lignocellulosic micro/nanofibers (LCMNF) is presented. This procedure allows increasing paper strength avoiding an excessive loss in drainability. LCMNF were obtained from partially delignified kraft pine sawdust using a high-pressure homogenizer. C...
The present work analyzes the effect of process variables and the method of characterization of cellulose micro/nanofibers (CMNFs) obtained by different treatments. A chemical pre-treatment was performed using oxalic acid at 25 wt.% and 50 wt.%. Moreover, for mechanical pre-treatments, a rotary homogenizer or a PFI mill refiner were considered. For...
This work investigates film formation using polyelectrolyte complexes (PECs) of xylan and polyethylenimine (PEI). Different xylan/PEI mass ratios (from 50/50 to 90/10) and pH values (5.0 and 7.0) are analyzed and both parameters have an effect on complex size and film properties. Furthermore, the mass ratio corresponding to the neutralization charg...
The present work analyzes the production and characterization of cellulose micro/nanofibers (CMNFs) obtained from different treatments. A chemical pre-treatment was performed using oxalic acid at 25 wt.% and 50 wt.%. Besides, a rotary homogenizer or a PFI mill refiner were used for mechanical pretreatments. Then, mechanical fibrillation to obtain C...
Sugar cane is a promising raw material for the extraction of hemicelluloses. An alkali treatment of sugar cane bagasse under proper conditions followed by a precipitation using a reasonable quantity of ethanol can be an effective method to isolate these polysaccharides. In this work, bagasse is treated to obtain two products: (a) polymeric hemicell...
Novel hemicellulose-based films from polyelectrolyte complexes (PECs) of chitosan and xylan from sugar cane bagasse were prepared and characterized. PEC suspension from two different xylan to chitosan mass ratios (70/30 and 80/20) were considered. With the aim of shorten the whole film preparation process, PEC suspension was concentrated through a...
The influence of the processing conditions and composition on the properties of biocomposites made of a bioplastic matrix from soybean protein, crosslinked with glutaraldehyde, reinforced with lignocellulosic material from wood sawdust (Wood Bio-Plastic Composite, WBPC) was investigated. The WBPCs were obtained by thermocompression applying a press...
Hydrogels were prepared from colloidal suspensions of polyelectrolyte complexes of xylan (Xyl) and chitosan (Ch) (mass ratio: 70 wt% Xyl/30 wt% Ch). They were formed at pH 5.0, at which both polyelectrolytes were highly charged according to their corresponding potentiometric titrations. They were treated with a polycarboxylic acid, sodium citrate,...
This work analyzes the main characteristics of hemicellulose alkali and peroxide/alkali extracted from sugar cane bagasse and precipitated by 1:1 ethanol/liquor ratio and studies the influence of the chemical charge on these characteristics. It also evaluates the film forming capacity of these hemicelluloses when they are combined in a polyelectrol...
Hemicelluloses, the second most abundant polysaccharides in nature after cellulose, can be used for hydrogels, in packaging-films, or biomedical materials, among other purposes. In the case of eucalyptus wood, glucuronoxylans are the main constituents of hemicellulose. Hot water extraction can be used as a pretreatment for purposes of hydrolysis of...
Films from colloidal suspensions of cationic polyelectrolyte complexes of xylan (Xyl) and chitosan (Ch) were formed and characterized by measuring: oxygen and water vapor barrier properties, solubility, and mechanical properties. High xylan content (Xyl/Ch mass ratio: from 70/30 to 85/15) was used, and a low amount of plasticizer (10 wt% glycerol)...
Ceramic paper discs were made by employing a dual papermaking technique and by partially substituting cellulosic fibres by SiO2-Al2O3 ceramic ones. Ulexite (NaCaB5O6(OH)6·5(H2O)), extracted from the natural mineral, was added as a binder to give ceramic paper the necessary strength for its manipulation and catalytic use.
Either La,Co or Ba,Co was i...
Cationic (CatPECs) and anionic (AnPECs) polyelectrolyte complexes from xylan and chitosan were formed, characterized and adsorbed onto unbleached fibers for improving the papermaking properties. They were prepared at a level of 30% of neutralization charge ratio by modifying the order of addition of polyelectrolytes and the ionic strength (0.01 N a...
The effects of three different fungal treatments on several technology characteristics of Eucalyptus grandiswood, were studied on industrial chips and blocks. The percentage of the substrate mass loss by the fungal treatment, and the relative amount of extractives and lignin were determined. The effective capillarity of wood, pH and total reducing...
The adsorption behavior of polyelectrolyte complexes (PECs) of poly(allylamine hydrochloride) (PAH) and 4-O-methylglucuronoxylan (Xyl) onto silica surface, cellulose nanofibrils (CNFs) model surfaces, and unbleached softwood kraft fibers was studied. Different charge ratios and ionic strengths of the liquid medium (q
−/q
+: 0.3, 0.5 and 0.8 in 1 mM...
Catalytic ceramic papers were developed by incorporating Pt-NaY zeolite to ceramic papers. The nec-essary mechanical strength was enhanced by the addition of natural borate compounds, which confer elasticity and resistance similar to those obtained using colloidal sus-pensions, which are the most commonly used binders. Pt-NaY zeolite was incorporat...
A deep understanding of alkali impregnation including the profiles of alkali concentration and hemicellulose degradation is necessary to analyze the optimization of current and innovative processes. In this paper, the impregnation of Scots pine (Pinus sylvestris L.) wood is analyzed and modeled under consideration of deacetylation, reactions of aci...
In this work, polyelectrolyte complexes (PECs) were formed by adding polyacrylic acid (PAA) or 4-O-methylglucuronoxylan (Xyl) on poly(allylamine hydrochloride) (PAH) solutions, at different ionic strength and neutral pH. Turbidity curves, charge densities of the cationic complexes determined by polyelectrolyte titration method, and z- potential val...
The effects of the dual-polyelectrolyte adsorption of poly(allylamine hydrochloride) (PAH) and lignosulfonate (LS) on a recycled unbleached softwood kraft pulp were studied and the method used for the determination of LS concentration was discussed. Adsorption isotherms of LS on untreated and on previously PAH-treated pulps at neutral pH, and diffe...
The relative ion transport capacity of wood – the “effective capillary cross sectional area” (ECCSA) – is determined in this work, based on the analogy with the relation between the electrical conductivities of wood and liquid medium. Wood was treated under different conditions and then the corresponding ECCSA A (the index A is for alkali) is estim...
During the impregnation stage of a Kraft cooking, dynamic changes occur in wood properties due to the alkali action. Particularly, its ion transport capacity, the effective capillary cross sectional area (ECCSA), is changed due to chemical reactions and swelling. In this work, the ECCSA in the transverse wood direction has been determined for Pinus...
NaY zeolite-containing ceramic papers were prepared by a papermaking technique with a dual polyelectrolyte retention system that implied the use of cationic and anionic polymers. To improve their mechanical
properties, we found that some borate compounds could be successfully used as ceramic binders. Three types of sodium and/or calcium borates wer...
The effects of a double polyelectrolyte adsorption of poly(allylamine hydrochloride) (PAH) and xylan (Xyl) on a recycled unbleached softwood kraft pulp were studied. The kinetics of PAH adsorption on this pulp was analyzed by building adsorption isotherms and by estimating the surface nitrogen adsorbed through the X-ray photoelectron spectroscopy (...
In wood pulping processes, the quality of the impregnation stage has a significant influence on the final pulp properties. In this work, a refined version of a previously published model is used to analyze this operation stage. For liquor containing NaOH and Na2S, the study considers the reaction of wood acetyls and acidic groups. The Donnan effect...
Polyelectrolytes containing amine functional groups such as PAH (poly(allylamine hydrochloride)) can be useful, under certain conditions, for improving paper strength. In this work, the charge density of PAH was determined at different pH and ionic strengths; PAH adsorption onto the cellulosic fibers was characterized, and the effects of low PAH do...
This work analyzes the application of a ceramic paper to the diesel soot combustion reaction in air. The catalytic paper is made of ceramic fibers, cerium oxide and potassium nitrate. The synthesis of this material is easy and fast, and provides a high-temperature resistant paper that can be readily adapted to different conformations and geometries...
The effects of the Fenton reagent on recycled unbleached pulp in the absence and presence of a model chemical contaminant, the p-hydroxybenzoic acid (HBA), were studied. In the absence of HBA, the Fenton system clearly modified the chemical and papermaking properties of the pulp. The kappa number was reduced and the specific light absorption coeffi...
Wood impregnation is crucial in any pulping process. The impregnation of chips of eucalyptus wood by a liquor of constant alkali concentration is here analyzed. A mass balance that considers kinetics of the main reactions and a dynamic diffusion coefficient is applied for the six chemical species analyzed. The diffusion rate is assumed dependent on...
The removal of native acetyl groups from hardwood O-acetyl-glucuronoxylan has a strong effect on physical characteristics, accessibility and structure of this polymer. The removal also has effects on the swelling and ion transport capacity of the cell wall of hardwoods. In this work, a kinetic expression for Eucalyptus wood deacetylation is determi...
The main shortcoming of the papermaking properties of recycled fibres refers mainly to the hornification effect, as a consequence of drying during papermaking. An alkaline treatment is potentially useful to reverse this effect. The present paper discusses the consequences of alkaline and alkaline peroxide treatments on unbleached recycled softwood...
The authors studied the oxidative and delignifying effects of the Trametes hirsuta laccase-HBT (1-hydroxybenzotriazole) system (LMS) on the papermakmg properties of an unbleached recycled softwood kraft pulp. The effects of pulp washing with a non-ionic surfactant (Tween 20) as a way to recover the enzyme and the effects of a final alkaline treatme...
Wood diffusion is strongly affected by the effective capillary cross-sectional area (ECCSA), which is the area of paths available for diffusion. The ECCSA varies dynamically according to the conditions and progress of the alkaline action. The alkali diffusion in natural wood is a complex process in the course of which the local transport properties...
Oxidative treatments, without and with assistance of a Laccase-Mediator System (LMS), were characterized in relation to their effects on the chemical composition and strength properties of the fibrous fraction of an unbleached recycled softwood kraft pulp. The LMS, composed of a Trametes hirsuta laccase extract and 1-hydroxybenzotriazole (HBT), was...
Medium or high charge density cationic polyelectrolytes are frequently used for water treatment. In the papermaking wet-end they are used as retention agents or as flocculating aids. Negative polyelectrolytes that enter the papermaking system increase the demand for cationic poly-electrolytes. Polyelectrolyte concentration can be determined by the...
Alkali impregnation is modelled on the basis of a mass balance which considers the main chemical reactions and the changes in transport capacity of the wood under different conditions. The deacetylation is considered as the controlling reaction and is used to establish the degree of chemical treatment. The Stone’s effective capillary concept, i.e....
This study evaluated the application of low levels of ozone at medium consistency to improve the properties of old corrugated container (OCC) pulp. Pulps obtained from kraft liner and corrugating medium were also tried. Ozone reduces the kappa number of the pulp, but the surface charge of the fiber is not changed. Ozonation clearly increases the re...
The effects of drying on the properties of the recycled fibers of unbleached softwood kraft pulp are first analysed. It is shown how temperature and the drying conditions (under restraint or not) affect the papermaking properties of this pulp. The consequences of the presence of a cationic starch adsorbed onto the cellulosic fibers on the surface c...
Alkali impregnation can be thought of as a process of reactive diffusion in which a moving front separates a reacted, swollen outer zone from an intact inner zone. In the alkaline impregnation of hardwood,the reaction zone becomes wider, and its movement slows, but the mechanism is always the same. The advance of the impregnation front can be deter...
A method commonly used to measure surface charge is the quantification of the polyelectrolyte adsorption capacity of the fibers. A linear cationic polyelectrolyte with high charge density and high molecular mass, pDMDAAC (poly-dimethyldiallylammonium chloride), is used under the assumption that it does not penetrate the micropores of the cell wall....
When wood undergoes an acidic or alkaline chemical action or a moderate thermal action, acetyl groups are easily removed. As deacetylation favourably increases the accessibility of the cell wall and the fibre swelling, mechanical properties of wood and responses of wood to pulping are modified. In this paper, the importance of the deacetylation eff...
The pattern of alkaline impregnation of eucalyptus and pinewood under industrial conditions, i.e. presteaming and pressurized impregnation, is analyzed. Differences between the external and central zones in the log section for 8-year-old Eucalyptus grandis and between earlywood and latewood of 25-year-old Pinus elliottii wood are examined. Profiles...
The specific modification of the removing of lignin from recycled high-kappa number pulps could be an alternative for improving their paper-making properties. In this series of experiments the application of a ligninolytic enzyme was considered. Virgin softwood kraft pulp was refined, dried, repulped and classified to obtain the R30 fraction as sta...
Alkali impregnation can be thought of as a process of reactive diffusion in which a moving front separates a reacted, swollen outer zone from an intact inner zone. In the alkaline impregnation of hardwood, the reaction zone becomes wider, and its movement slows, but the mechanism is always the same. The advance of the impregnation front can be dete...
The problem of optimizing the alka- line impregnation of wood chips is posed and solved under usual restrictions. The cost to be optimized balances opposite criteria by taking economics and product quality into account, and is conditioned by the system dynamics. Evolution is modeled from typical transport phenomena equations. Optimiza- tion is atta...
The action of alkali on milled and solid poplar wood is analyzed under medium levels of alkali concentration and temperatures below 100degreesC. Under these conditions, as much as 6% NaOH on wood can be consumed by deacetylation and other chemical reactions. For both transverse directions of solid wood, profiles of the alkali concentration are anal...
The action of alkali on milled and solid poplar wood is analyzed under medium levels of alkali concentration and temperatures below 100°C. Under these conditions, as much as 6% NaOH on wood can be consumed by deacetylation and other chemical reactions. For both transverse directions of solid wood, profiles of the alkali concentration are analyzed a...
In order to analyse the fundamentals of alkaline chemi-mechanical pulping of hardwoods, the chemical state of the wood was related to both the swelling level of fibres and the papermaking properties of pulp. Wafers of poplar wood were alkali treated following a factorial experimental design for two variables: temperature and alkali concentration. T...
A mathematical model describing isothermal alkali diffusion and reaction with acetyl groups in moist wood chips was derived and validated against experiments. A coupled mass balance for the acetyl groups and the alkali was posed and solved numerically. Differences observed earlier between model-predicted and experimentally obtained alkali concentra...
The impregnation pattern of alkali in fresh Cottonwood is analysed. Isothermal process, medium alkali-concentration, temperature below 100°C and tangential direction are considered. The degree of deacetylation in the wood is taken as an indicator of the whole chemical action of the alkali. Profiles of alkali concentration, alkali content, liquid co...
and time between 15 and 60 minutes. Experimental data, i.e. treatment yield, chemical consumption, acid groups content and
swelling measured by WRV are fitted to polynomial equations. The relationship between swelling and the chemical state of the
wood is analysed. The evolution of swelling reaches maximum levels within the time period. The ionic c...
The low temperature alkaline treatment of Cottonwood (Populus deltoides) was studied by applying a factorial experimental design. The effects of treatment time and alkali concentration on alkali consumption, as well as treatment yield, carboxyl groups and acetyl groups contents were investigated. Relationships between these contents and wood swelli...
The quantitative determination of acetyl groups in milled cottonwood treated with alkali by IR spectroscopy is presented. The diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy quantification is based on the variation of the peak height at 1735 cm(-1) due to the hemicellulose carbonyl groups, which is then normalised to the 1510cm(...
The kinetics of alkaline deacetylation of cottonwood (Populus deltoides) was experimentally studied. In order to minimize resistance to mass and heat transfer, wood meal (40/60 mesh) was employed. Wood samples were isothermally treated with alkali which was maintained at constant concentration. The temperature range was 50-90 degrees C and the alka...
Factors determining the quality of mechanical and alkaline chemi-mechanical pulps from bagasse are discussed. It is shown that intense depithing notably reduces silica content and metal ions, and improves bagasse brightness. Mechanical and chemimechanical pulps obtained at two working scales are compared. At a higher scale, properties of the cleane...
The effects of digestion variables alkali charge and temperature on bagasse defibrability and semichemical pulp properties are analyzed. A 3 × 4 factorial experimental design is applied for an alkali charge ranging from 8 to 11% NaOH and a temperature ranging from 100 to 145°. Second order regression models show a strong effect of cooking temperatu...
The effect of temperature and alkali charge on a 20-minute soda-semichemical bagasse pulping is analyzed. A 3x4 factorial experimental design is applied for an alkali charge ranging from 8 to 11 % and temperature ranging from 100 to 145 ºC. Special attention is paid to the region of high cooking temperature. While hemicellulose content of pulp is n...
The main effects of mild alkaline action on poplar wood are studied. The changes in water retention value (WRV) with the treatment time are analyzed as parameters of wood swelling. The WRV is related to carboxyl and acetyl group contents, which are both strongly affected. While carboxyl group content, as measured by ionic exchange capacity, increas...
The effects of sodium hydroxide charges up to 5% in cold soda chemimechanical pulping of thoroughly depithed bagasse were studied. Tear and tensile increase notably and light scattering coefficient decreases with increasing alkali. In addition to these properties, drastic changes are observed in refining energy, minishives and sheet porosity for so...
The effects of wet depithing of fresh and stored bagasse were initially studied. Intense wet depithing in the presence of a chelating agent reduces colour and metal ions content. The effects of sodium hydroxide charge up to 5% on o.d. bagasse in cold soda chemimechanical pulping of thoroughly depithed bagasse were later studied. Pretreatment at 90o...
A non-convencinal refining for chemimechanical pulp for paper is tested at laboratory scale. A controlled mechanical action over the pulp aggregates is intended, such aggregates being made to roll between highly rough continuous surfaces. The practical feasibility of the process is verified and, in addition, the different effects produced are compa...
Refining by rolling of nodules of pulp between rough plane disks is studied. The mechanism is conceives as an alternative refining, able to attain a greater internal fibrillation in comparison with usual refinings, as a way of improving the present quality of chemimechanical pulps. The rolling refining of sugar cane bagasse chemimechanical pulp in...
In most research papers on the characterization and evaluation of mechanical pulps, the characterization factors correspond to the average fiber length and shape of the particles in the pulp. Taking into account that the drainage behavior is important in evaluating a pulp, the authors studied the drainage phenomenon as it occurs in the standard she...
Es ampliamente aceptada la importancia de la carga superficial de las fibras celulósicas en la
interacción con otras fibras o cargas minerales y principalmente en la formación del enlace
interfibrilar. El método de la adsorción de polielectrolitos en medio acuoso se está utilizando en
forma creciente para estimar la carga superficial de las fibras...
Medium or high charge density cationic polyelectrolytes are frequently used for the treatment of wastewater, as retention agent or as flocculating aids. Negative polyelectrolytes can enter in the system and increase the cationic polyelectrolyte demand. The polyelectrolyte concentration can be determined by colloidal titration as well as by streamin...
Se analizan los efectos de la aplicación de ozono sobre pulpas de reciclo de papel kraft linerindustrial. El estado químico de la pared fibrosa es caracterizado por la carga superficial de lasfibras y el número kappa de la pulpa. De las propiedades papeleras se analizan especialmentelas propiedades de papeles para embalaje por ser este el destino m...
In pulping processes, the homogeneity of the chemical treatment and the quality and yield of the pulp obtained are strongly affected by the quality of the alkaline impregnation. In this work, unidirectional differential balance of the impregnating phenomenon is applied considering the main species and chemical reactions and, in addition, the speed...
Questions
Question (1)
Have you compared the chelation capacity of your complexes with traditional chelating agent in terms of equilibrium constant?
Projects
Projects (3)
Analyze variables and effect of hot water treatment as a pre-treatment for pulping and any other bio-refinery process.
Analyze alkali impregnation and extraction for biomass.
I am working in the synthesis of structured catalysts for two reactions mainly. One of these reactions is the catalytic combustion of soot, in this case the objective is the manufacture of diesel particulate filter (DPF), currently we are using two type of structured: ceramic paper (Al2O3:SiO2) and wire mesh (stainless steel). The other reaction is the oxidative deshidrogenación of ethane for producing ethylene; in this case we are working with different, metallic and ceramic structures.