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Pedro Jorge Carvalho

Pedro Jorge Carvalho
CICECO - Aveiro Institute of Materials, University of Aveiro · Chemistry department

Doctor of Philosophy

About

128
Publications
27,292
Reads
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6,834
Citations
Additional affiliations
February 2018 - present
University of Aveiro
Position
  • Professor (Assistant)
Description
  • Thermodynamics of Chemical Processes
September 2017 - present
University of Aveiro
Position
  • Professor (Assistant)
Description
  • Draft Project in Chemical Engineering
February 2017 - July 2017
University of Aveiro
Position
  • Professor (Assistant)
Description
  • Laboratory B1-MIA
Education
March 2008 - March 2011
University of Aveiro
Field of study
  • Chemical Engineering
December 2007 - April 2008
University of Aveiro
Field of study
  • Chemical Engineering - Measurements of Thermophysical Properties of Perfluorocarbons and Ionic Liquids

Publications

Publications (128)
Article
In the past years large efforts have been placed in the development of novel separation techniques with improved resolution, simplicity, speed and easy to scale-up. Among these, ionic-liquid-based (IL-based) aqueous biphasic systems (ABS) have been broadly proposed for the separation of high-value compounds, allowing improved extraction performance...
Article
Full-text available
The present study focused on the methodology for identification of the wastewater stream that presents the highest phenolic impact at a large oil refinery. As a case-study, the oil refinery, Petrogal S.A., in Sines, Portugal, was selected. Firstly, stripped sour water from the cracking complex was identified as the most relevant wastewater stream c...
Article
The compound 1,3-dimethyl-1,3-diazinan-2-one (N,N’-dimethylpropyleneurea, DMPU) is a dipolar aprotic solvent with very strong electron-donating abilities but which is much less toxic and less carcinogenic than similar solvents such as the widely used HMPA (hexamethylphosphorictriamide). This paper reports densities and viscosities of the binary mix...
Article
With the increasing number of applications being reported for protic ionic liquids (PILs), there is a demand for the development of thermodynamic models that can accurately describe their thermophysical properties and phase equilibria, with equations of state (EoS) derived from the Statistical Associating Fluid Theory (SAFT) being among the best. T...
Article
Full-text available
A cloud point evaluation was performed for the nonionic surfactant Tergitol 15-S-7 in aqueous solutions of McIlvaine buffer (pH 7.0). Cloud point temperatures of the selected nonionic surfactant were studied in relation to the effect that the addition of dicationic ionic liquids (ILs) had on the systems. The dicationic ILs with different alkyl spac...
Article
New experimental density data in a wide range of temperatures (283–363) K and pressures (0.1–95) MPa is here reported for five protic ILs based on the N,N-diethylethanolammonium ([DEEA]) cation, combined with the following anions: acetate ([Ace]), propanoate ([Prop]), butanoate ([But]), pentanoate ([Pent]) and hexanoate ([Hex]) in a 1:1 acid:base p...
Article
The synthesis of protic ionic liquids based in carboxylate anions, too often admitted as being straightforward, is actually challenging and must be carefully addressed. This review discusses the importance of oligomeric anions, in particular those based on carboxylates, in the behavior and nature of protic ionic liquids. There is strong evidence in...
Article
The partitioning behavior of norfloxacin (more hydrophilic) and sodium diclofenac (more hydrophobic) was studied considering the use of aqueous two-phase systems (ATPSs) based in copolymers and dextran. For this research, the phase behavior of systems composed of water, a copolymer (Pluronic PE6400, Pluronic L35, Pluronic PE6800, PEG-ran-PPG monobu...
Article
Technologies for wastewater reclamation and water reuse within oil refineries have been gaining particular attention over the past decade due to legislative pressures associated with the efficient use of water resources and wastewater discharge. Having to constantly rely on access to great amounts of water, the oil and gas industry has been seeking...
Article
Dehydration technologies with low energy consumption using non-toxic materials are important in industrial, residential, and transport applications. Herein, nanocomposite polymeric hollow fibers with high dehydration capability were demonstrated with the incorporation of green amino acid-based ionic liquids. The ionic liquid was encapsulated in des...
Article
Natural bioactive compounds have been attracting growing interest from the industries as a "greener" alternative to synthetic raw materials/products. Rhodotorula glutinis yeast naturally synthesizes added value compounds such as lipids and carotenoids, commonly used for cosmetic, pharmaceutical, and food applications. R. glutinis constitutes a rigi...
Article
This work is inserted in a research program that consists mainly in the experimental and theoretical study of gas/liquid solubility in ionic liquids (ILs). In this study the experimental data of hydrogen sulfide solubility in ammonium-based ionic liquids, namely 2-hydroxyethylammonium acetate [2-HEA][Ace], bis(2-hydroxyethyl)ammonium acetate [B-2-H...
Article
With the increase use of plastics, there is currently a concern with the waste of materials, resulting in a series of challenges and opportunities for the waste management sector. In the present work, poly(ethylene terephthalate) (PET) foam was produced from recycled PET (RPET) from used water bottles. The recycled material was manually prepared an...
Article
Two tricyanomethanide-based ionic liquids (ILs), namely 1-ethyl-3-methylimidazolium tricyanomethanide ([C2C1im][TCM]) and 1-butyl-4-methylpyridinium tricyanomethanide ([4-C4C1py][TCM]) have been recently reported as effective solvents for the BTX extractive distillation from pyrolysis gasoline. The vapor-liquid or vapor-liquid-liquid equilibria (VL...
Article
Ionic liquids have gathered special attention due to their potential for carbon dioxide capture, and their potential as solvents for climate changes mitigation. Following the scope of previous works, amino acid‐based ionic liquids encapsulated (ENILs) into carbonaceous submicrocapsules are here proposed as a novel material for CO 2 capture. The ENI...
Article
Due to the costs involved, the capture of CO2 in post-combustion is not currently seen as economically viable. Aiming at changing the perception of post-combustion CO2 from a costly and non-profitable process to a valuable commodity and fostering the development of the next-generation of technologies, novel solvents and their mixtures have been inv...
Article
Tricyanomethanide-based ionic liquids (ILs) are, probably, the most interesting ILs for separation purposes considering their low viscosity and high thermal stability but mainly due to their enhanced performance in a wide number of applications. However, the scarce high pressure density data (ρpT) limits the development of robust models for process...
Article
In this work, new experimental data on the isobaric vapor-liquid equilibria (VLE) of binary aqueous systems, with six different glycol ethers (glymes), some of which are currently used in the Selexol process, were measured at three different pressures, namely 0.05, 0.07, and 0.1 MPa. From the experimental data, the water activity coefficients were...
Article
Technologies for water recycling within oil refineries have been gaining interest at an extensive rate due to the large volume of wastewater generated, high dependency of water and the progressive scarcity of this valuable resource. Phenols are part of a specific class of organic pollutants that have been contributing to a low-quality effluent in o...
Article
Full-text available
The use of cork granules for cleaning up crude oil or oil derivative spills and further oil recovery appears as a promising option due to their unique properties, which allow a high oil sorption capacity, low water pickup and excellent reuse. The present work reports the effect of oil viscosity on cork sorption capacity by using five types of oils...
Article
Extractive distillation using tricyanomethanide-based ionic liquids (ILs) has been shown to be a promising and feasible process for effectively separate aromatics from pyrolysis gasolines. The high performance of these mass agents has been reported by evaluating simple synthetic n-heptane/toluene binary mixtures, on a wide temperature and solvent t...
Article
The aromatic/aliphatic separation using ionic liquids (ILs) has been proposed as an enhanced technology when compared to conventional liquid-liquid extraction and extractive distillation processes. Some ILs show extractive properties (distribution ratios and selectivities) greater than those of conventional solvents, like sulfolane and N-methylpyrr...
Article
The evidence for surface crystallization in ionic liquids is scarce. The existing reports seem to be contradictory as for its driving forces, since in the two compounds investigated in the literature, the contribution of coloumbic and van der Walls forces are very different. In this work the 1-dodecyl-3-methylimidazolium tetrafluoroborate was studi...
Article
Given the recent boom of applications for deep eutectic solvents (DES), there is a need for robust and accurate thermodynamic models that are able to describe them. Recent works have used molecular-based equations of state, derived from the Statistical Associating Fluid Theory (SAFT), to model DES due to their ability to explicitly account for hydr...
Article
Full-text available
The order of the salting-in or salting-out inducing ability of ions on the aqueous solubility of macromolecules in aqueous solutions is known as the Hofmeister series. Taking into account that ionic liquids (ILs) are constituted by ions, they can exert similar effects on the solubility of other ILs in aqueous media. To expand the knowledge of the s...
Article
Despite the large spectrum of applications being reported for DESs over the last decade, their thermodynamic characterization is often neglected, hindering a better understanding of their nature, and the development of accurate and robust thermodynamic models to describe them, essential for the conceptual and design stages of new industrial process...
Article
Full-text available
Given the recent boom of applications for deep eutectic solvents (DES), there is a need for robust and accurate thermodynamic models able to describe them. Recent works have used molecular-based equations of state, derived from the Statistical Associating Fluid Theory (SAFT), to model DES due to their ability to explicitly account for hydrogen bond...
Article
The water impact on the CO2 and CH4 solubilities and their selectivity in [C4C1im][Ac] was evaluated for [C4C1im][Ac]:H2O molar ratios of 5:1, 2:1, 1:1, and 1:2, for temperatures ranging from (293 to 363) K and pressures up to 70 MPa. In addition, density and excess molar volumes of [C4C1im][Ac] + water binary systems were measured aiming at unders...
Article
Full-text available
In this work, an experimental protocol to determine liquid-liquid phase diagrams of aqueous two-phase systems (ATPS) in a chemical engineering course is described. Throughout this laboratory set of experiments, students will determine liquid-liquid ternary phase diagrams, comprising the solubility curves, tie-lines, tie-line lengths and critical po...
Article
Full-text available
The development of specific 'green' solvents with unique combination of properties and associated techniques for target applications, capable of minimizing the environmental impact from their use in chemical production or by developing sustainable and renewable energy and resources, has been gathering increasing attention over the last years. Emerg...
Article
The development of specific ‘green’ solvents with unique combination of properties and associated techniques for target applications, capable of minimizing the environmental impact from their use in chemical production or by developing sustainable and renewable energy and resources, has been gathering increasing attention over the last years. Emerg...
Article
The alkanolammonium ILs are protic ionic liquids (PILs) with low cost of preparation, simple synthesis and purification methodologies and low toxicity. The knowledge of high-pressure density and speed of sound are fundamental properties either to understand the nature of molecular interactions, structure and packing effects or to determine other th...
Article
This work covers the phase equilibrium characterization of systems containing n-heptane, toluene, and two tricyanomethanide-based ionic liquids (ILs), namely 1-ethyl-3-methylimidazolium tricyanomethanide ([C2C1im][TCM]) and 1-butyl-4-methylpyridinium tricyanomethanide ([4-C4C1py][TCM]). Aiming at evaluating these ILs for the n-heptane/toluene extra...
Article
This work provides a comprehensive evaluation of the effect of the cation alkyl side chain length of the 1-alkyl-3-methylimidazolium chloride series ([C n C1im]Cl, n = 2-14) of ionic liquids (ILs) on their capability to form aqueous biphasic systems (ABSs) with salts and self-aggregation derived properties. The liquid-liquid phase behavior of tern...
Article
Isobaric vapor liquid equilibria (VLE) of binary mixtures of the ionic liquid (IL) 1-butyl-3-methylimidazolium trifluoromethanesulfonate (C4mimTfO) with either water or short chained n-alkyl alcohols (methanol, ethanol, propan-1-ol and butan-1-ol) are described in this study. Two different microebulliometers and a classical VLE apparatus were compa...
Article
The study of carbon dioxide (CO2) solubility in different solvents is important for the development of carbon capture and storage (CCS) technologies as well as for enhanced oil recovery (EOR) through CO2 injection. Using two different experimental methodologies, based on the synthetic method, the high-pressure solubilities of CO2 in four glymes, na...
Article
The alkanolammonium ILs are protic ionic liquids (PILs) with huge potential in a variety of industrial fields. Among other advantages, these PILs have low cost of preparation, simple synthesis and purification methodologies and low toxicity. This study aims at obtaining significant data on the fundamental thermophysical properties of hydroxyethylam...
Article
We present new experimental data on the isobaric vapor–liquid equilibria (VLE) of four binary mixtures of water with ethylene glycol, diethylene glycol, triethylene glycol, or tetraethylene glycol, measured at three different system pressures (0.05, 0.07, and 0.1 MPa). Water activity coefficients were estimated from the mixtures boiling temperature...
Conference Paper
The design, simulation and/or optimization of new processes rely on the availability of robust and accurate models or equations of state (EoS). However, traditional cubic equations of state (EoS’s), traditionally used in many process simulators, fail on describing complex polar and associating behavior of some molecules, leading to unreliable resul...
Article
The knowledge of critical properties is fundamental in engineering process calculations for the estimation of thermodynamic properties and phase equilibria. A literature survey shows a large number of methods for predicting critical properties of different classes of compounds, but no previous study is available to evaluate their suitability for te...
Article
Ionic liquids (ILs) have been object of extensive research during the last years due to their potential for industrial application with special interest on carbon dioxide (CO2) capture. Nonetheless, ILs transport properties have stand out as the major drawback for their use on absorption applications. This work proposes ionic liquids encapsulated (...
Article
The design and optimization of industrial processes relies on the availability of robust and accurate models and equations of state (EoS). Aiming at further advancing soft-SAFT EoS, towards its implementation on industrial processes, a methodology to determine the molecular model and transferable molecular parameters is here discussed. In addition...
Article
New experimental density data of six glycols, namely ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TriEG), tetraethylene glycol (TeEG), pentaethylene glycol (PeEG) and hexaethylene glycol (HeEG), and a polyethyleneglycol (PEG 400) were determined in a wide range of temperatures (283–363 K) and pressures (0.1–95) MPa. The experi...
Article
A systematic isobaric vapor-liquid equilibrium (VLE) study of seven binary mixtures of 1-butyl-3-methylimidazolium chloride, [C4C1im][Cl], and methanol, propan-1-ol, propan-2-ol, butan-1-ol, butan-2-ol, tert-butanol (2-methylpropan-2-ol), iso-butanol (2-methylpropan-1-ol) and pentan-1-ol, was carried out at three different system pressures (0.1, 0....
Article
We have investigated, both theoretically and experimentally, the balance between the presence of alkyl and perfluoroalkyl side chains on the surface organization and surface tension of fluorinated ionic liquids (FILs). A series of ILs composed of 1-alkyl-3-methylimidazolium cations ([CnC1im] with n = 2, 4, 6, 8, 10 or 12) combined with the perfluor...
Article
Ionic liquids are undeniably interesting compounds, with a wide range of potential applications and the ability to be designed to meet a specific set of requirements. This does not mean however that their application can be successful in all fields. These solvents have been object of extensive research for physical sorption of CO2 and a number of m...
Article
The speed of sound in the protic ionic liquids (PILs) N-methyl-2-hydroxyethylammonium butyrate (m2HEAB) and N-methyl-2-hydroxyethylammonium pentanoate (m2HEAP) was measured at atmospheric pressure, and over the range of temperatures T=(293.15 to 343.15) K. The speed of sound and density of aqueous mixtures of the ionic liquid were also determined t...
Article
Experimental data for density, viscosity, refractive index and sound speed of 11 glycols and glymes were measured in the temperature range between (283.15 and 373.15) K and at atmospheric pressure. The compounds evaluated include ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TriEG), tetraethylene glycol (TeEG), ethylene glycol...
Article
Ionic liquids (ILs) with cyano-functionalized anions are a set of fluids that are still poorly characterized despite their remarkably low viscosities and potential applications. Aiming at providing a comprehensive study on the influence of the number of -CN groups through the surface tension and surface organization of ILs, the surface tensions of...
Article
Isobaric vapor-liquid equilibria of 1-butyl-3-methylimidazolium thiocyanate ([C4C1im][SCN]), 1-butyl-3-methylimidazolium dicyanamide ([C4C1im][N(CN)2]), 1-butyl-3-methylimidazolium tricyanomethanide ([C4C1im][C(CN)3]) and 1-ethyl-3-methylimidazolium tetracyanoborate ([C2C1im][B(CN)4]), with water and ethanol were measured over the whole concentrati...
Article
In order to evaluate the impact of the alkyl side chain length and symmetry of the cation on the thermophysical properties of water-saturated ionic liquids (ILs), densities and viscosities as a function of temperature were measured at atmospheric pressure and in the (298.15 to 363.15) K temperature range, for systems containing two series of bis(tr...
Conference Paper
The operation of modern industrial plants would be very difficult, if not impossible, without automation and computer control. Safe efficient plant operation requires that thousands of process variables, like temperature, pressure, flow rate, liquid level, and chemical composition, be controlled within specified limits on a regular basis (as often...
Conference Paper
Full-text available
The operation of modern industrial plants would be very difficult, if not impossible, without automation and computer control. Safe efficient plant operation requires that thousands of process variables, like temperature, pressure, flow rate, liquid level, and chemical composition, be controlled within specified limits on a regular basis (as often...
Article
Full-text available
Abstract Experimental data for density, viscosity, refractive index and surface tension are reported, for the first time, in the temperature range between 288.15 and 353.15 K and at atmospheric pressure for two protic ionic liquids, namely 2-(dimethylamino)-N,N-dimethylethan-1-ammonium acetate, [N11{2(N11)}H][CH3CO2], and N-ethyl-N,N-dimethylammoni...
Article
A new high pressure cell was developed to measure the high pressure phase behavior of gas + aqueous salt solutions and validated through the measurement, and comparison against literature data, of two systems, the H2O + CO2 and H2O + CO2 + NaCl, at temperatures up to 363 K and pressures up to 13 MPa. As previously reported by others, a salting out...