Imperial College London

George JACKSON BSc DPhil FRSC FRS

Faculty of EngineeringDepartment of Chemical Engineering

Professor of Chemical Physics
 
 
 
//

Contact

 

+44 (0)20 7594 5640g.jackson Website

 
 
//

Location

 

RODH 605Roderic Hill BuildingSouth Kensington Campus

//

Summary

 

Publications

Publication Type
Year
to

331 results found

Bernet T, Wehbe M, Febra SA, Haslam AJ, Adjiman CS, Jackson G, Galindo Aet al., 2024, Modeling the Thermodynamic Properties of Saturated Lactones in Nonideal Mixtures with the SAFT-γ Mie Approach., J Chem Eng Data, Vol: 69, Pages: 650-678, ISSN: 0021-9568

The prediction of the thermodynamic properties of lactones is an important challenge in the flavor, fragrance, and pharmaceutical industries. Here, we develop a predictive model of the phase behavior of binary mixtures of lactones with hydrocarbons, alcohols, ketones, esters, aromatic compounds, water, and carbon dioxide. We extend the group-parameter matrix of the statistical associating fluid theory SAFT-γ Mie group-contribution method by defining a new cyclic ester group, denoted cCOO. The group is composed of two spherical Mie segments and two association electron-donating sites of type e1 that can interact with association electron-accepting sites of type H in other molecules. The model parameters of the new cCOO group interactions (1 like interaction and 17 unlike interactions) are characterized to represent target experimental data of physical properties of pure fluids (vapor pressure, single-phase density, and vaporization enthalpy) and mixtures (vapor-liquid equilibria, liquid-liquid equilibria, solid-liquid equilibria, density, and excess enthalpy). The robustness of the model is assessed by comparing theoretical predictions with experimental data, mainly for oxolan-2-one, 5-methyloxolan-2-one, and oxepan-2-one (also referred to as γ-butyrolactone, γ-valerolactone, and ε-caprolactone, respectively). The calculations are found to be in very good quantitative agreement with experiments. The proposed model allows for accurate predictions of the thermodynamic properties and highly nonideal phase behavior of the systems of interest, such as azeotrope compositions. It can be used to support the development of novel molecules and manufacturing processes.

Journal article

Valsecchi M, Galindo A, Jackson G, 2024, Modelling the thermodynamic properties of the mixture of water and polyethylene glycol (PEG) with the SAFT-γ Mie group-contribution approach, Fluid Phase Equilibria, Vol: 577, ISSN: 0378-3812

The SAFT-γ Mie group-contribution (GC) equation of state (EoS) is employed to describe the thermodynamic properties of aqueous mixtures of polyethylene glycol (PEG), a polyether of great industrial and scientific interest. This prototypical system is chosen due to the intrinsic complexity of hydrogen-bonding polymers, and represents a critical test of the theory. Water is modelled as a single Mie segment with four association sites and PEG as a linear heteronuclear chain of three types of segments: the associating hydroxymethyl end group (CH2OH); the associating oxygen (cO); and the modified methylene group (CH2OE), which incorporates the effects that the proximity of an electronegative atom has on the electronic environment of the methylene group. The SAFT-γ Mie model parameters characterizing the newly-defined group interactions are estimated to reproduce the liquid–liquid equilibrium (LLE) closed-loop miscibility gaps observed in the orthobaric phase diagram of PEG + water mixtures. The resulting model allows one to predict miscibility gaps in a temperature range between 350 K and 600 K, capturing both the UCST and the LCST within a 2% error with a close description of the overall phase behaviour. The predictive capability of the model is assessed by comparing the calculations with the experimental density of pure PEG, the enthalpy of mixing, and vapour–liquid equilibrium properties of PEG + water mixtures, with a good overall agreement. By coupling the present SAFT model with a recent thermodynamic model describing solubility in semi-crystalline polymers, the solubility of water in PEG below its melting point is semi-quantitatively captured both in the low- and high-humidity regimes. In particular, deliquescence – the melting of semi-crystalline PEG at high relative humidity – is predicted by simply accounting for the melting enthalpy of PEG crystals.

Journal article

Valsecchi M, Galindo A, Jackson G, 2023, Modeling Sorption of Hydrocarbons in Polyethylene with the SAFT-γ Mie Approach Combined with a Statistical-Mechanical Model to Describe Semicrystalline Polymers., Macromolecules, Vol: 56, Pages: 9952-9968, ISSN: 0024-9297

A recently developed statistical-mechanical model is applied systematically to estimate the fraction of tie-molecules (polymer chains linking different crystals directly or via entanglements) in semicrystalline polyethylene (PE) samples. The amorphous domains of the polymer are divided into constrained interlamellar domains and "free" outer-lamellar domains. A set of model parameters is assigned to each sample by correlating previous experimental measurements and minimizing the difference between the predicted solubility of pure hydrocarbons in the sample and the experimental values. We show that the sorption isotherms of multiple pure fluids in each sample can be described by a single parameter set, proving that the polymer-solute interactions (described accurately by the SAFT-γ Mie EoS) are decoupled from the sample-specific properties of the polymer. We find that ∼30% of the crystalline stems in the lamellae of PE are connected to tie-molecules, within the bounds suggested by previous theoretical and computational work. The transferability of the sample-specific parameters is assessed by predicting cosolubility effects and solubility at different temperatures, leading to good agreement with experimental data.

Journal article

Lee YS, Jackson G, Galindo A, Adjiman CSet al., 2023, A predictive model for the techno-economic assessment of CO<inf>2</inf> chemisorption processes applicable to a large number of amine solvents, Chemical Engineering Research and Design, Vol: 200, Pages: 615-636, ISSN: 0263-8762

With the growing need to reduce carbon dioxide (CO2) emissions, there have been substantial efforts to identify new solvents that can improve the overall performance of chemical-absorption CO2 capture processes. Given the large number of potential solvents, computer-aided molecular and process design (CAMPD) approaches can play a critical role in accelerating the search for optimal solvents by enabling the systematic exploration of solvent candidates and process conditions. One of the challenges in developing such a framework is the requirement for a process model that can be used to capture the interactions between process performance and solvent structure without significantly increasing its numerical complexity. In the current work, a model for the absorption–desorption of CO2 is developed using the predictive SAFT-γ-Mie group-contribution approach, allowing the performance of numerous solvents to be assessed without the need for extensive experimental data. In order to avoid convergence difficulties when solving this highly nonlinear model, a tailored initialization strategy is established, using an adapted inside-out algorithm to prime a nonlinear equation solver for each column, providing a good initial guess for the whole flowsheet. Tests on three solvents confirm the robustness of the approach. Building on this enhanced numerical stability, the model is validated by comparison against pilot-plant data, showing good accuracy. A detailed parametric study of the effect of the key process variables is undertaken; the important role of the CO2 capture rate, of the lean solvent temperature and loading, and of the desorber pressure is highlighted. The results of the parametric study are used to formulate an optimization problem which is successfully solved for four solvents. A large reduction in total annualized cost and energy requirements is achieved by tuning the operating conditions to each solvent considered. The predictive capability, robustness

Journal article

Herdes C, Galindo A, Jackson G, 2023, Thermodynamics 2022 conference, University of Bath, Bath, UK, 7-9 September 2022, MOLECULAR PHYSICS, ISSN: 0026-8976

Journal article

Lee YS, Galindo A, Jackson G, Adjiman CSet al., 2023, Enabling the direct solution of challenging computer-aided molecular and process design problems: chemical absorption of carbon dioxide, Computers and Chemical Engineering, Vol: 174, Pages: 1-24, ISSN: 0098-1354

The search for improved CO₂ capture solvents can be accelerated by deploying computer-aided molecular and process design (CAMPD) techniques to explore large molecular and process domains systematically. However, the direct solution of the integrated molecular-process design problem is very challenging as nonlinear interactions between physical properties and process performance render a large proportion of the search space infeasible. We develop a methodology that enables the direct and reliable solution of CAMPD for absorption–desorption processes, using the state-of-the-art SAFT-γ Mie group contribution approach to predict phase and chemical equilibria. We develop new feasibility tests and show them to be highly efficient at reducing the search space, integrating them in an outer-approximation algorithm. The framework is applied to design an aqueous solvent and CO₂ chemical absorption–desorption process, with 150 CAMPD instances across three case studies solved successfully. The optimal solvents are more promising than those obtained with sequential molecular design approaches.

Journal article

Wehbe M, Haslam AJ, Garcia-Munoz S, Jackson G, Galindo Aet al., 2023, Thermodynamic modelling of the nature of speciation and phase behaviour of binary and ternary mixtures of formaldehyde, water and methanol, MOLECULAR PHYSICS, ISSN: 0026-8976

Journal article

Perdomo FA, Khalit SH, Graham EJ, Tzirakis F, Papadopoulos AI, Tsivintzelis I, Seferlis P, Adjiman CS, Jackson G, Galindo Aet al., 2023, A predictive group-contribution framework for the thermodynamic modelling of CO absorption in cyclic amines, alkyl polyamines, alkanolamines and phase-change amines: New data and SAFT- Mie parameters, Fluid Phase Equilibria, Vol: 566, Pages: 1-27, ISSN: 0378-3812

A significant effort is under way to identify improved solvents for carbon dioxide (CO) capture by chemisorption. We develop a predictive framework that is applicable to aqueous solvent + CO mixtures containing cyclic amines, alkyl polyamines, and alkanolamines. A number of the mixtures studied exhibit liquid–liquid phase separation, a behaviour that has shown promise in reducing the energetic cost of CO capture. The proposed framework is based on the SAFT- Mie group-contribution (GC) approach, in which chemical reactions are described via physical association models that allow a simpler, implicit, treatment of the chemical speciation characteristic of these mixtures. We use previously optimized group interaction parameters between some amine groups and water (Perdomo et al., 2021), and develop new group interactions for the cNH, cN, NH2, NH, N, cCHNH, and cCHN groups with CO2; a set of second-order group parameters are also developed to account for proximity effects in some alkanolamines. A combination of literature data and new experimental measurements for the absorption of CO2 in aqueous cyclohexylamine systems obtained in our current work, are used to develop and test the proposed models. The SAFT- Mie GC approach is used to predict the thermodynamics of selected mixtures, including ternary phase diagrams and mixing properties relevant in the context of CO2 capture. The current work constitutes a substantial extension of the range of aqueous amine-based solvents that can be modelled and thus offers the most comprehensive thermodynamically consistent platform to date to screen novel candidate solvents for CO2 capture.

Journal article

Jackson G, 2023, Announcement of the winner of the Longuet-Higgins Early Career Researcher Prize 2022, Molecular Physics, Vol: 121, ISSN: 0026-8976

In molecular ro-vibrational calculations, it is desirable to build a symmetry-adapted basis set where both the rotational and vibrational functions are each separately symmetrised. Enabling rotational symmetrisation requires the use of body-fixed frames whose rotations under molecular symmetry operations are constant. The familiar Eckart and Sayvetz frames are examples of such frames, as are bisector frames for certain molecules. In this work, we introduce alternative frames for CH3Cl-type molecules and C2H6 that can be used for rotational symmetrisation. These are defined by the vibrational coordinates without the need for a reference geometry. We also provide one method to find such frames. Finally, we state a straightforward transformation of the s-vectors when changing frames which facilitates the evaluation of kinetic energy operators in these non-standard frames.

Journal article

Fayaz Torshizi M, Graham E, Adjiman C, Galindo A, Jackson G, Muller Eet al., 2023, SAFT-Υ force field for the simulation of molecular fluids 9: Coarse-grained models for polyaromatic hydrocarbons describing thermodynamic, interfacial, structural, and transport properties, Journal of Molecular Liquids, Vol: 369, ISSN: 0167-7322

Coarse-grained models of polyaromatic hydrocarbons parametrized by employing the SAFT- Mie approach are presented and assessed by comparison with experimental data and all-atom models in their ability to describe liquid densities, isothermal compressibilities, thermal expansivities, viscosities, and interfacial tensions. The structural behaviour characterized by the center of mass and angular radial distribution functions are also benchmarked. The SAFT- Mie force field models are shown to deliver quantitatively accurate predictions while promising significant speedups in the computational cost of performing molecular dynamics simulations.

Journal article

Perdomo FA, Jackson G, Galindo A, Adjiman CSet al., 2023, An approach for modelling simultaneous fluid-phase and chemical-reaction equilibria in multicomponent systems via Lagrangian duality: The Reactive HELD algorithm., Computer Aided Chemical Engineering, Pages: 973-978

An approach for the calculation of simultaneous phase and chemical-reaction equilibria and stability that does not require any assumptions on the number of stable phases and is applicable to any number of reactions is presented. It is based on an extension of the dual extremum principle concept for non-reactive systems (HELD) formulated in terms of the Helmholtz energy, where additional constraints are introduced that relate molar amounts and extents of reaction. The extended R-HELD algorithm is applied to reacting mixtures such as the esterification of acetic acid and the formation of methyl tert-butyl ether.

Book chapter

Jackson G, 2022, Joan Henri van der Waals (1920-2022) OBITUARY, MOLECULAR PHYSICS, Vol: 120, ISSN: 0026-8976

Journal article

Kournopoulos S, Santos MS, Ravipati S, Haslam AJ, Jackson G, Economou IG, Galindo Aet al., 2022, The Contribution of the Ion-Ion and Ion-Solvent Interactions in a Molecular Thermodynamic Treatment of Electrolyte Solutions, JOURNAL OF PHYSICAL CHEMISTRY B, Vol: 126, Pages: 9821-9839, ISSN: 1520-6106

Journal article

Graham EJ, Forte E, Burger J, Galindo A, Jackson G, Adjiman CSet al., 2022, Multi-objective optimization of equation of state molecular parameters: SAFT-VR Mie models for water, Computers and Chemical Engineering, Vol: 167, ISSN: 0098-1354

The determination of a suitable set of molecular interaction parameters for use with an equation of state (EoS) can be viewed as a multi-objective optimization (MOO) problem, where each objective quantifies the quality of the description for a particular type of thermodynamic property. We outline a methodology for the determination of a set of Pareto-optimal interaction parameters. The Pareto front is generated efficiently using a sandwich algorithm where one solves a sequence of weighted-sum scalarized single objective optimization problems. The algorithm presented can be used for any number of objective functions, allowing for the consideration of multiple thermodynamic property types as competing objectives in the MOO. The methodology is applied to the determination of suitable parameter sets for models of water within the SAFT-VR Mie framework. Three competing property targets are considered as objective functions: saturated-liquid density, vapour pressure and isobaric heat capacity. Two different types of molecular models are considered: spherical models of water, and non-spherical model of water. We analyse the two- and three-dimensional Pareto surfaces and parameter sets obtained for different property combinations in the MOO. The proposed methodology can be used to provide a rigorous comparison between different model types. Numerous Pareto-optimal parameter sets for SAFT-VR Mie water models are documented, and we recommend two new models (one spherical model and one non-spherical model) with an appropriate compromise between the competing objectives.

Journal article

Valsecchi M, Ramadani J, Williams D, Galindo A, Jackson Get al., 2022, Influence of Tie-Molecules and Microstructure on the Fluid Solubility in Semicrystalline Polymers., J Phys Chem B - Special Issue in Honor of Doros N. Theodorou

Predicting the absorption of gases and liquids in semicrystalline polymers is of critical importance for numerous applications; the mechanical and transport properties of these materials are highly dependent on the amount of solutes dissolved in their bulk. For most semicrystalline polymers which are in contact with an external fluid, the observed uptake of the solute is found to be lower than that predicted by treating the amorphous domains of the polymer as subcooled polymer melts at the same thermodynamic state. This observation has recently led to the hypothesis that the amorphous domains effectively behave as polymer liquids subject to an additional "constraint pressure" which reduces the equilibrium solubility in the domains. We present a new statistical mechanical model of semicrystalline polymers. The constraint pressure emerges naturally from our treatment, as a property of the interlamellar amorphous domains caused by the stretching and localization in space of the tie-molecules (polymer chains linking different lamellae). By assuming that the interlamellar domains exchange monomers reversibly with the lamellae, the model allows one to simultaneously predict the increase of constraint pressure at low temperatures and the variation of the lamellar thickness as a function of temperature─a phenomenon known as premelting. The sorption isotherms of a range of fluids in different polyethylene and polypropylene samples are determined experimentally and the data is compared with calculations of the new model using the SAFT-VR Mie EoS. In order to accurately predict the absorption close to the vapor pressure of the penetrant, we find that it is essential to include the "free", unconstrained amorphous domains in the description, resulting in a multiscale model with two adjustable parameters (the fractions of tie-molecules and free amorphous domains) that characterize the morphology of a given semicrystalline polymer sample. The trends observed fo

Journal article

Wehbe M, Haslam AJ, Jackson G, Galindo Aet al., 2022, Phase behaviour and pH-solubility profile prediction of aqueous buffered solutions of ibuprofen and ketoprofen, FLUID PHASE EQUILIBRIA, Vol: 560, ISSN: 0378-3812

Journal article

Walker PJ, Zhao T, Haslam AJ, Jackson Get al., 2022, Ab initio development of generalized Lennard-Jones (Mie) force fields for predictions of thermodynamic properties in advanced molecular-based SAFT equations of state, JOURNAL OF CHEMICAL PHYSICS, Vol: 156, ISSN: 0021-9606

Journal article

Kournopoulos S, Haslam AJ, Jackson G, Galindo A, Schoen Met al., 2022, Molecular theory of the static dielectric constant of dipolar fluids, The Journal of Chemical Physics, ISSN: 0021-9606

Journal article

Lee YS, Jackson G, Galindo A, Adjiman CSet al., 2022, Development of a Bi-Objective Optimisation Framework for Mixed-Integer Nonlinear Programming Problems and Application to Molecular Design, Computer Aided Chemical Engineering, Pages: 1225-1230

We present a novel algorithm (SDNBI) to tackle the numerical challenges associated with the solution of bi-objective mixed-integer nonlinear programming problems (BO- MINLPs), with a focus on the exploration of nonconvex regions of the Pareto front. The performance of the algorithm as measured by the accuracy of the resulting approximation of the Pareto front in the disconnected and nonconvex domain of Pareto points is assessed relative to two multi-objective optimisation (MOO) approaches: the sandwich algorithm (SD) and the modified normal boundary intersection (mNBI) method. The features of these MOO algorithms are evaluated using two published benchmark models and a molecular design problem. Initial results indicate that the new algorithm presented outperforms both the SD and the mNBI method in convex, nonconvex-continuous, combinatorial problems, both in terms of computational cost and of the overall quality of the Pareto-optimal set.

Book chapter

Jonuzaj S, Burcham CL, Galindo A, Jackson G, Adjiman CSet al., 2022, Optimizing the selection of drug-polymer-water formulations for spray-dried solid dispersions in pharmaceutical manufacturing, Computer Aided Chemical Engineering, Pages: 2185-2190

In this work we present a systematic computer-aided design methodology for identifying optimal drug-polymer-water formulations with desired physical and chemical properties that are used in the spray drying of drug products. Within the proposed method, the UNIFAC model is employed to predict the solubility and miscibility of binary and ternary mixtures, whereas the Gordon-Taylor equation is used to estimate the glass transition temperature of a wide range of chemical blends. The design methodology is applied to the selection of optimal drug-polymer blends that maximize the loading of naproxen, while ensuring that stable formulations are designed. Finally, we explore the trade-offs between two competing objectives through multiobjective optimization, where the drug loading and water-content of API-polymer-water blends are maximized simultaneously. A ranked list of optimal solutions (mixtures with different chemicals and compositions) that can be used to guide experimental work is obtained by introducing integer cut inequalities into the model.

Book chapter

Evans R, Frenkel D, Galindo A, Jackson Get al., 2021, Special issue in honour of Michael L. Klein FRS, MOLECULAR PHYSICS, Vol: 119, ISSN: 0026-8976

Journal article

Papadopoulos AI, Perdomo FA, Tzirakis F, Shavalieva G, Tsivintzelis I, Kazepidis P, Nessi E, Papadokonstantakis S, Seferlis P, Galindo A, Jackson G, Adjiman CSet al., 2021, Molecular engineering of sustainable phase-change solvents: From digital design to scaling-up for CO<sub>2</sub> capture, CHEMICAL ENGINEERING JOURNAL, Vol: 420, ISSN: 1385-8947

Journal article

Schoen M, Evans R, Gubbins KE, Rabe JP, Thommes M, Jackson Get al., 2021, Gerhard Findenegg (1938-2019), MOLECULAR PHYSICS, Vol: 119, ISSN: 0026-8976

Journal article

Ravipati S, Simoes Santos M, Economou I, Galindo A, Jackson G, Haslam AJet al., 2021, Monte Carlo molecular simulation study of carbon dioxide sequestration into dry and wet calcite pores containing methane, Energy and Fuels, Vol: 35, Pages: 11393-11402, ISSN: 0887-0624

We perform grand canonical Monte Carlo (GCMC) simulations to study the adsorption of carbon dioxide in a calcite slit pore. The injection of carbon dioxide is simulated by increasing the chemical potential of carbon dioxide, which allows for an investigation of adsorption under varying carbon dioxide loadings. The study is carried out for three different environments: an empty pore; a pore containing methane; and a pore containing methane with trace amounts of water. We systematically investigate the impact of the presence of these other fluids on carbon dioxide adsorption. We study the influence of carbon dioxide loading on fluid density in the pore and examine individual fluid-density profiles (in the direction normal to the fluid–solid interface). The order of fluid adsorption affinity to the surface is found to be water > carbon dioxide > methane. The interpretation of our results is informed by the examination of free-energy-averaged fluid–substrate potentials, which are computed independently from the simulations. Our observations suggest that ignoring the presence of water could lead to overestimation not only of methane availability but also of carbon dioxide storage capacity in pores, with important consequences in, for example, modeling carbon dioxide sequestration in calcite-rich reservoirs. Ultimately, it is hoped that the molecular-level insights from this study will aid the multiscale modeling of reservoir fluids in the context of enhanced oil recovery and carbon dioxide sequestration.

Journal article

Febra SA, Bernet T, Mack C, McGinty J, Onyemelukwe II, Urwin SJ, Sefcik J, ter Horst JH, Adjiman CS, Jackson G, Galindo Aet al., 2021, Extending the SAFT-gamma Mie approach to model benzoic acid, diphenylamine, and mefenamic acid: Solubility prediction and experimental measurement, Fluid Phase Equilibria, Vol: 540, Pages: 1-20, ISSN: 0378-3812

The prediction of the solubility of active pharmaceutical ingredients (APIs) is a significant challenge whichis of importance in pharmaceutical applications and solvent selection. Here, we extend the table of groupinteractions (3 like interactions, 47 unlike interactions) of the SAFT-γ Mie group-contribution equation ofstate to model the phase behaviour and solubility of mefenamic acid, a nonsteroidal anti-inflammatorydrug, in a range of solvents. In addition to mefenamic acid, we also consider its molecular synthons:benzoic acid and diphenylamine. New experimental solubility data are presented for the three moleculesin a range of solvents, and three new SAFT-γ Mie functional groups are defined (aCCOOH, aCNHaC andCH3CO) and characterised, together with their interactions with solvent groups. Literature data for thevapour pressure, single-phase density, saturation density, vapourisation enthalpy, bubble temperature,dew temperature, and bubble pressure are used to characterise the new group interactions. Solubilitydata are used to characterise the new group-group interactions only if there are no other experimentaldata available. The transferability and predictive accuracy of the new models are assessed by comparing the theoretical predictions with the experimental solubility data. Our comparison includes alcohols,ketones, and esters as families of solvents and mixed-solvent solubility predictions.

Journal article

Morgado P, Barras J, Galindo A, Jackson G, Felipe Eet al., 2021, Solubility of water in mixtures of (n-alkanes + n-perfluoroalkanes) and in n-perfluoroalkylalkanes: experimental and modeling with the SAFT-γ Mie group-contribution approach, Molecular Physics: An International Journal at the Interface Between Chemistry and Physics, Vol: 119, ISSN: 0026-8976

The solubility of water in liquid n-perfluorohexane and in an equimolar mixture of n-hexane + n-perfluorohexane is experimentally determined as a function of temperature. The solubility of water in the equimolar mixture is significantly higher than the average of the solubilities in the pure solvents suggesting, for the first time, that mixing hydrogenated and perfluorinated chains enhances the solubility of water. The solubility in the equimolar mixture of n-hexane + n-perfluorohexane is also determined theoretically with the SAFT-γ Mie group-contribution approach, allowing a direct quantitative estimate of how much the large deviations from ideality contribute to the solubility of water in the mixture. In addition, the SAFT-γ Mie approach is used to represent the solubility of water in a number of n-perfluoroalkylalkanes, covering a range of relative lengths of the hydrogenated and perfluorinated chains. The theory can be used to predict the relative extent of the solubility of water in the different solvents, in good agreement with the experimental data. This is accomplished by using a single parameter to describe the strong attractive interaction between water and the CH2CF2 group at the junction between the hydrogenated and perfluorinated segments, which is known to be responsible for the increased solubility of water in these substances.

Journal article

Watson OL, Jonuzaj S, McGinty J, Sefcik J, Galindo A, Jackson G, Adjiman CSet al., 2021, Computer aided design of solvent blends for hybrid cooling and antisolvent crystallization of active pharmaceutical ingredients, Organic Process Research and Development, Vol: 25, Pages: 1123-1142, ISSN: 1083-6160

Choosing a solvent and an antisolvent for a new crystallization process is challenging due to the sheer number of possible solvent mixtures and the impact of solvent composition and crystallization temperature on process performance. To facilitate this choice, we present a general computer aided mixture/blend design (CAMbD) formulation for the design of optimal solvent mixtures for the crystallization of pharmaceutical products. The proposed methodology enables the simultaneous identification of the optimal process temperature, solvent, antisolvent, and composition of solvent mixture. The SAFT-γ Mie group-contribution approach is used in the design of crystallization solvents; based on an equilibrium model, both the crystal yield and solvent consumption are considered. The design formulation is implemented in gPROMS and applied to the crystallization of lovastatin and ibuprofen, where a hybrid approach combining cooling and antisolvent crystallization is compared to each method alone. For lovastatin, the use of a hybrid approach leads to an increase in crystal yield compared to antisolvent crystallization or cooling crystallization. Furthermore, it is seen that using less volatile but powerful crystallization solvents at lower temperatures can lead to better performance. When considering ibuprofen, the hybrid and antisolvent crystallization techniques provide a similar performance, but the use of solvent mixtures throughout the crystallization is critical in maximizing crystal yields and minimizing solvent consumption. We show that our more general approach to rational design of solvent blends brings significant benefits for the design of crystallization processes in pharmaceutical and chemical manufacturing.

Journal article

Lindeboom T, Zhao B, Jackson G, Hall CK, Galindo Aet al., 2021, On the liquid demixing of water plus elastin-like polypeptide mixtures: bimodal re-entrant phase behaviour, PHYSICAL CHEMISTRY CHEMICAL PHYSICS, Vol: 23, Pages: 5936-5944, ISSN: 1463-9076

Journal article

Cummings PT, Harold MP, Hall CK, Jackson GG, Palmer JCet al., 2021, A tribute to Keith E. Gubbins, AIChE Journal, Vol: 67, ISSN: 0001-1541

Journal article

Jackson G, Perdomo Hurtado FA, Khalit SH, Adjiman CS, Galindo Aet al., 2021, Description of the thermodynamics and fluid-phase behaviour of aqueous solutions of linear, branched, and cyclic amines, AIChE Journal, Vol: 67, Pages: 1-19, ISSN: 0001-1541

The SAFT‐ɣ Mie group‐contribution equation of state is used to represent the fluid‐phase behaviour of aqueous solutions of a variety of linear, branched, and cyclic amines. New group interactions are developed in order to model the mixtures of interest, including the like and unlike interactions between alkyl primary, secondary, and tertiary amine groups (NH2, NH, N), cyclic secondary and tertiary amine groups (cNH, cN), and cyclohexylamine groups (cCHNH, cCHN) with water (H2O). The group‐interaction parameters are estimated from appropriate experimental thermodynamic data for pure amines and selected mixtures. By taking advantage of the group‐contribution nature of the method, one can describe the fluid‐phase behaviour of mixtures of molecules comprising those groups over broad ranges of temperature, pressure, and composition. A number of aqueous solutions of amines are studied including linear, branched aliphatic, and cyclic amines. Liquid‐liquid equilibria (LLE) bounded by lower critical solution temperatures (LCSTs) have been reported experimentally and are reproduced here with SAFT‐ɣ Mie approach. The main feature of the approach is the ability not only to represent accurately the experimental data employed in the parameter estimation, but also to predict the vapour‐liquid, liquid‐liquid, and vapor‐liquid‐liquid equilibria, and LCSTs with the same set of parameters. Pure compound and binary phase diagrams of diverse types of amines and their aqueous solutions are assessed in order to demonstrate the main features of the thermodynamic and fluid‐phase behaviour.

Journal article

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-html.jsp Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00170163&limit=30&person=true