Solvent Blends Research Articles

Cyrene™ blends: a greener solvent system for organic syntheses

A Cyrene™ blend system was developed using “viscosity blending” to lower the viscosity of Cyrene™. The solvent blends were successfully used in many applications in chemical syntheses.

Castor-oil based polyurethane/NiCo-OLDH nanocomposites with improved flame retardant properties

Polymer nanocomposites are known for improved thermal properties, mechanical properties, gas permeability and flame retardant properties compare to neat polymer matrix or conventional composites. Polymer matrix nanocomposites are widely used in defense use, equipment, automobiles and aircraft components, housings, packaging, coating applications. The present work aims to prepare polymer matrix nanocomposites to improve the flame retardant properties of a matrix where reinforcement is flame retardant in nature. The castor-oil based polyurethane has been synthesized by reacting castor-oil and isophorone diisocyanate which is flammable. It is very important to mention that inorganic nanofillers i.e. layered double hydroxides have been used as a reinforcement in castor-oil based polyurethane to increase the flame retardant, thermal and mechanical properties of nanocomposites. In this study, nickel–cobalt organomodified layered double hydroxide (NiCo-OLDH) has been prepared by the co-precipitation method. The prepared NiCo-OLDH has been characterized by various techniques. The average particle size of the OLDH nanoparticles is 68 nm as analyzed by particle size analyzer. The morphology of the OLDHs are in fibril form as shown in transition electron microscopy (TEM). The different weight percentages of NiCo-OLDH (1.5–5%) have been incorporated into synthesized castor oil based polyurethane (COBPU) to prepare COBPU/NiCo-OLDH nanocomposites using solvent blending method and characterized by FTIR, XRD, SEM, TGA techniques. FTIR has been used to confirm the functional group and metal oxide present in the nanocomposites. COBPU/NiCo-OLDH nanocomposites have shown a 10 % improvement in thermal stability and an increased in tensile strength of 26% as compared to neat COBPU. Flame retardancy as measured by LOI of the nanocomposites are in the range of 23–28%.

Role of Polyamine as a Promoter in Enhancing Co2 Absorption in a Piperazine and Methyldiethanolamine Solvent Blend System: Comparative Study and Economic Assessment

Role of Polyamine as a Promoter in Enhancing Co2 Absorption in a Piperazine and Methyldiethanolamine Solvent Blend System: Comparative Study and Economic Assessment

Solubility, solvent effect, enthalpy–entropy compensation and solvation thermodynamics of 4-(bromomethyl)-2(1H)-quinolinone in several aqueous blends

The current study was mainly devoted to solubility for the systems formed by 4-(bromomethyl)-2(1H)-quinolinone (BMQ) and blended solvents of isopropanol, N-methyl-2-pyrrolidinone (NMP), ethanol and n-propanol with water. Experiments for solubility determination were conducted by employing the shake-flask equilibration method from 278.15 to 318.15 K under 101.2 kPa. For each aqueous cosolvent mixture, the minimum solubility was recorded in water at 278.15 K; and the maximum value, in neat organic solvents at 318.15 K. The solubility performance was illustrated by Hansen solubility parameters of water, BMQ and co-solvents. No occurrence of polymorphic transformation or solvation was observed after experiments based on the XRD spectra of raw BMQ and excess solids analyzed. The satisfactory correlation results for solubility data was obtained by modified Wilson model, mixture response surface model, modified van’t Hoff-Jouyban–Acree model and Jouyban–Acree model. The relative average deviations were calculated to be no more than 8.72 %. Investigation on the relative contributions from inter- and intra-molecular interactions to the solubility variation of BMQ at temperature of 298.15 K was quantitatively performed via the linear solvation energy relationships (LSER). The descriptors of solvent blends including solubility parameter, dipolarity-polarizability and hydrogen-bond basicity were primarily responsible for the solubility variation. As well, the preferential solvation of BMQ was researched quantitatively via the inverse Kirkwood–Buff integrals method on the basis of some obtainable properties of solvent blends. The positive preferential solvation parameters for BMQ in middle and cosolvent-rich blends strongly suggest that the crystalline solute of BMQ is preferentially solvated by cosolvents of isopropanol, NMP, ethanol and n-propanol. The transfer and apparent dissolution properties including apparent Gibbs energy change (298.15 K), dissolution enthalpy and dissolution entropy (298.15 K) were derived and discussed. Analysis of enthalpy–entropy compensation indicates the entropy-driven mechanism of BMQ dissolved in all blend solvents.

Regeneration of CO2‐rich aqueous amine‐ionic liquid blends in CO2 capture process

AbstractIn this present work, solvent regeneration of CO2‐rich aqueous solvent blends containing Monoethanolamine (MEA) and Ionic liquids was studied experimentally. The ionic liquids (ILs) used are tetrabutylammonium acetate [TBA][OAC] and tetrabutylammonium bromide [TBA][Br]. The solvent mixture composition of ILs are 2, 5, 10 wt% and their respective MEA as 28, 25, 20 wt%. CO2 absorption and desorption process were performed using solvent blends. The recovery of solvent was performed for three different temperatures 358, 368 and 373 K. The findings reveal that solvent blends of MEA with [TBA][Br] exhibit higher regeneration efficiency and lower regeneration energy than MEA with [TBA][OAC] blends with a minimum composition of 2 wt% [TBA][Br]. Energy consumption for recovery of 2 wt% [TBA][Br] blend with 28 wt% MEA was found to be 65.66 KJ mole−1 of CO2 which is 41.97% less than 30 wt% MEA. Furthermore, physicochemical properties such as pH, density, viscosity, carbon loading and surface tension have been measured before and after CO2 absorption and desorption process. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.

Designing Safer Solvents to Replace Methylene Chloride for Liquid Chromatography Applications Using Thin-Layer Chromatography as a Screening Tool

Methylene chloride, commonly known as dichloromethane (DCM), is a widely used chemical for chromatography separation within the polymer, chemical, and pharmaceutical industries. With the ability to effectively solvate heterocyclic compounds, and properties including a low boiling point, high density, and low cost, DCM has become the solvent of choice for many different applications. However, DCM has high neurotoxicity and is carcinogenic, with exposure linked to damage to the brain and the central nervous system, even at low exposure levels. This research focuses on sustainability and works towards finding safer alternative solvents to replace DCM in pharmaceutical manufacturing. The research was conducted with three active pharmaceutical ingredients (API) widely used in the pharmaceutical industry: acetaminophen, aspirin, and ibuprofen. Thin-layer chromatography (TLC) was used to investigate if an alternative solvent or solvent blend could show comparable separation performance to DCM. The use of the Hansen Solubility Parameter (HSP) theory and solubility testing allowed for the identification of potential alternative solvents or solvent blends to replace DCM. HSP values for the three APIs were experimentally determined and used to identify safer solvents and blends that could potentially replace DCM. Safer solvents or binary solvent blends were down-selected based on their dissolution power, safety, and price. The down-selected solvents (e.g., ethyl acetate) and solvent blends were further evaluated using three chemical hazard classification approaches to find the best fitting nonhazardous replacement to DCM. Several safer solvent blends (e.g., mixtures composed of methyl acetate and ethyl acetate) with adequate TLC performance were identified. Results from this study are expected to provide guidance for identifying and evaluating safer solvents to separate APIs using chromatography.

Applications of NIR spectroscopy and chemometrics to illicit drug analysis: An example from inhalant drug screening tests

The “loló” stands out among the most used inhalant drugs in Brazil. This drug is a non-specific blend of organic solvents, traditionally composed of ether and chloroform. Reports in the literature and forensic practice have revealed changes in the composition profile of this drug, based on availability of acquisition. This diversity has an effect on the efficiency of the preliminary tests used to detect illicit substances in situations that require rapid response time from the criminal investigations, such as arrests in the act. Considering the diversity of volatile substances with potential use as inhalant drugs and the limited detection abilities of preliminary exams routinely used by forensic laboratories, this present work applied NIR spectroscopy associated with chemometric models to detect the presence of organic solvents in samples of “loló”. Initially, the chemical profile of the seized samples was surveyed in the geographic region of study (Paraiba State, Brazilian northeast), and from the observation of the prevalent substances, classification models were produced using samples made in the laboratory and samples from real apprehensions. Then, an analysis protocol was developed, based on SIMCA models, to detect the predominant solvents in the regional composition profile (dichloromethane, trichloroethene and chloroform). The proposed analysis protocol obtained an overall accuracy of 94.7% in detecting halogenated hydrocarbons in suspect samples and 100% accuracy in characterizing the composition of samples composed exclusively of the studied halogenated hydrocarbons and their binary mixtures. Considering that the colorimetric tests used in the routine of forensic laboratories do not detect many components, the proposed method was technically and economically viable in preliminary tests for samples seized as suspicious of being "loló".

Low-Mass Liquid Crystalline Materials Blended in Recycled Thermoplastic Polyester Elastomer for Corrosion Inhibitor Application

In this work, the development and application of multicomponents obtained from recycled polyethylene terephthalate (r-PET) waste and monotropic liquid crystals as anticorrosion coatings are reported. The r-PET raw material was alcoholyzed and reproduced as a thermoplastic polyester elastomer (TPEE) with different amounts (n%, n = 0, 1, 3, and 5) of 1,6-hexanediamine (HDA). Then, a fluorine-containing liquid crystal (4-cyano-3-fluorophenyl 4-ethylbenzoate (4CFE)) was incorporated into the TPEE mixture via solvent blending to modify and enhance the water resistance. The adhesion behavior of the coating on glass and iron substrates was evaluated by cross-cut tests and immersion tests in aqueous NaCl. In the corrosion resistance measurements, all of the coating samples fabricated with 10 ± 1 mm thickness were less active toward electrochemical corrosion (PEF% > 99%) than the bare iron plate, indicating that our work provided better protection against corrosion of the iron plate.

Identifying sustainable alternatives to dimethyl formamide for coating applications using Hansen Solubility Parameters

The toxicity of certain organic solvents utilized in industrial processes has been a major concern in the last few decades. The stricter regulations and increased public awareness around the use of toxic solvents are driving industries towards safer alternatives. Dimethyl formamide (DMF) is an important industrial solvent used to solubilize several polymers used in the coating industry (more than 200 thousand tons globally), especially polyurethanes (PU). However, DMF is toxic and can potentially create an unsafe work environment for workers, and therefore safer alternatives are needed. The Hansen Solubility Parameter (HSP) theory is one of the accepted methodologies used for predicting the solubility of polymers. Using the HSP principles and the Hansen Solubility Parameters in Practice (HSPiP) software, alternative solvent blends are identified for two commercial polyurethanes - Desmopan® and Desmocoll®. The alternative solvent blends dissolve the polymers at 25% w/w loading and have comparable costs to DMF. They are also less toxic in comparison to DMF. In addition, other physical properties like evaporation rate and boiling point are also matched. Coating trials are carried out using an industrial pilot coating line to ensure that the solvent system is a ‘drop-in’ replacement for DMF. This research establishes a methodology for rapidly identifying safer alternatives for various toxic solvents.

ISOLATION AND CHARACTERIZATION OF A SECONDARY METABOLITE FROM THE AERIAL PARTS OF Launaea (Lactuca) taraxacifolia

Launaea (Lactuca) taraxacifolia also known as wild lettuce is a medicinally important plant of the Asteraceae family. The plant was selected for this study due to its widespread use in traditional medicine and on the basis that the plant is almost going into extinct in Nigeria. The extraction was carried out by subjecting the air dried pulverized plant materials into trichloromethane solvent for a period of some days, followed by filtration and concentration. Separation and purification of the various constituents of the crude were done using thin layer and column chromatography. The mobile phases and solvent blends employed were: normal hexane, trichloromethane, ethyl ethanoate and methanol. The extraction, purification, concentration and chromatographic separations of the extracts were carried out at Post-graduates, chemistry laboratory, Michael Okpara University of Agriculture, Umudike, Nigeria. The NMR spectra analysis was investigated at Monash University Malaysia while the FTIR and GC-MS were carried out at Nanotechnology and Research Institute Malaysia. The NMR analysis was done using a Bruker VSP 500MHZ model machine. The GC-MS was performed using an Agilent 7000 model while the FTIR analysis was carried out on an Agilent 4500 series FTIR system. The structural elucidation of the proposed compound was deduced using GC-MS, FTIR, NMR (13C and 1H) and 2D COSY NMR spectra. This chemical investigation resulted in the isolation of a novel compound SB3 (Octadecahydro-10-(1,2,3,4-tetrahydronaphtalen-3-yl)-4,4-dimethoxy-6b,12b,14b-trimethyl Picen-3-(4H,6bH,14bH)-one. Compound SB3 was isolated using 50% hexane and 50% trichloromethane at an Rf value of 0.692. The MS spectrum of compound SB3 gave a molecular ion peak at m/z 545.81, which corresponded to a molecular formula of C37H53O3.

Solubility, solvation thermodynamics and solvent effect of thiabendazole in several cosolvent blends

Equilibrium solubility determination and model correlation were performed in the present research for the systems formed by solid solute of thiabendazole and binary aqueous blends of acetonitrile, methanol, n-propanol and isopropanol. Experiments at temperatures ranging from 283.15 to 323.15 K were conducted by the use of the shake-flask saturation technique at 101.2 kPa. For the given binary solvent blends, the minimum mole fraction solubility was recorded in water at 283.15 K; and the maximum one, in neat organic solvent at 323.15 K. The generated equilibrium solubility was satisfactorily described by two models, modified van’t Hoff-Jouyban–Acree and Jouyban–Acree, with the relative average deviations (%) of no more than 6.08. Good prediction results of extend Hildebrand solubility approach (relative average deviations < 4.10%) were observed in terms of quartic polynomial for the four solution systems to correlate the interaction parameter (W) and solubility parameters of the solvents’ blends in the absence of thiabendazole (δ1+2). Analysis of the relative contributions from intra- and inter-molecular interactions to solubility variation of solid solute of thiabendazole (298.15 K) was quantitatively carried out via the linear solvation energy relationships (LSER). The descriptors of blended solvents comprising solubility parameter and hydrogen-bond basicity were principally responsible for the variation of determined solubility. Besides, the preferential solvation of thiabendazole was quantitatively researched via the inverse Kirkwood–Buff integrals method on the basis of some accessible properties for blended solvent systems. The positive preferential solvation parameters for thiabendazole in the middle and cosolvent-rich blends powerfully suggested that thiabendazole was preferentially solvated by cosolvents of isopropanol, acetonitrile, n-propanol, ethanol and methanol. The conjecture was reasonable that in above compositions, thiabendazole mainly served as Lewis acidic in terms of its interactions with alcohol molecules; while for the acetonitrile mixtures, this behavior was contributed by polarization effect. Besides, thiabendazole was preferentially solvated by ethanol (2) in ethyl acetate (1) + ethanol (2) solutions with ethyl acetate-rich compositions, and by water (2) solvent in aqueous blends with rich water compositions.

The Influence of the Blend Ratio, Solvent Additive, and Post-production Treatment on the Polymer Dynamics in PTB7:PCBM Blend Films

The Influence of the Blend Ratio, Solvent Additive, and Post-production Treatment on the Polymer Dynamics in PTB7:PCBM Blend Films

Safer Solvent Blends for Food, Dye, and Environmental Analyses Using Reversed-Phase High Performance Liquid Chromatography

Liquid chromatography (LC) is a technique widely used to identify and quantify organic compounds in a complex mixture. Typical operations of high-performance liquid chromatography (HPLC) involve continuous use of harmful solvents. Replacing these harmful solvents with safer alternatives will provide significant environmental, health, and safety benefits. In this work, a systematic approach for searching safer solvent blends to replace acetonitrile for reversed-phase (RP) HPLC operations is presented. GreenScreen® for Safer Chemicals was used as the first filter to down-select safer solvent candidates from thousands of chemicals based on their safety ratings. A list of LC operation parameters was then employed to determine final solvent candidates. Finally, Hansen Solubility Parameters in Practice (HSPiP) software was utilized to identify the most probable compositions of blends from these solvents for actual LC testing. It was found that a blend of 75% ethanol and 25% methyl acetate by volume provided the chromatograms with the best performance, which had similar response factors and column efficiency compared to acetonitrile when surrogate food additives, dyes, and water pollutants were tested, suggesting that this solvent blend is a potential safer alternative to replace acetonitrile for certain LC applications.

Microwave-Assisted Two-Step Liquefaction of Acetone-Soluble Lignin of Silvergrass Saccharification Residue for Production of Biopolyol and Biopolyurethane.

The application of microwave heating facilitated efficient two-step liquefaction of acetone-soluble lignin obtained from saccharification residue of Miscanthus sacchariflorus (silvergrass), which was prepared by enzymatic hydrolysis, to produce biopolyol with a low acid number and favorable hydroxyl number. The acetone-soluble lignin was liquefied using a crude glycerol and 1,4-butanediol solvent mixture at various solvent blending ratios, biomass loadings, acid loadings, and reaction temperatures. The optimal reaction condition was determined at a solvent blending ratio of crude glycerol to 1,4-butanediol of 1:2, 20% of biomass loading, and 1% of catalyst loading at a reaction temperature of 140 °C for 10 min. Subsequently, the optimal biopolyol was directly used for the preparation of biopolyurethane foam as a value-added product. The chemical and physical properties of biopolyurethane foams derived from acetone-soluble lignin were characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and high-resolution scanning electron microscopy (HR-SEM). In addition, mechanical properties of produced biopolyurethane foams, including compressive strength and density, were also characterized to suggest their appropriate applications. The results indicated that the biopolyurethane foam can be used as a green replacement for petroleum-based polyurethane foam due to its comparable thermal properties, mechanical strength, and morphological structure.

Computer Aided Design of Solvent Blends for Hybrid Cooling and Antisolvent Crystallization of Active Pharmaceutical Ingredients.

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.

Polymers and Solvents Used in Membrane Fabrication: A Review Focusing on Sustainable Membrane Development.

(1) Different methods have been applied to fabricate polymeric membranes with non-solvent induced phase separation (NIPS) being one of the mostly widely used. In NIPS, a solvent or solvent blend is required to dissolve a polymer or polymer blend. N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide (DMF) and other petroleum-derived solvents are commonly used to dissolve some petroleum-based polymers. However, these components may have negative impacts on the environment and human health. Therefore, using greener and less toxic components is of great interest for increasing membrane fabrication sustainability. The chemical structure of membranes is not affected by the use of different solvents, polymers, or by the differences in fabrication scale. On the other hand, membrane pore structures and surface roughness can change due to differences in diffusion rates associated with different solvents/co-solvents diffusing into the non-solvent and with differences in evaporation time. (2) Therefore, in this review, solvents and polymers involved in the manufacturing process of membranes are proposed to be replaced by greener/less toxic alternatives. The methods and feasibility of scaling up green polymeric membrane manufacturing are also examined.

Asphaltene precipitation from heavy oil mixed with binary and ternary solvent blends

Abstract Models are required to predict the onset and precipitation of asphaltenes from mixtures of heavy oil and solvents for a variety of heavy oil applications. The regular solution approach is well suited for this objective but has not yet been tested on solvent mixtures. To do so, the onset and amount of asphaltene precipitation were measured and modeled for mixtures of heavy oil with solvent blends made up from n-alkanes, cyclohexane, and toluene at temperatures of 21 and 180 °C and pressures of 0.1 and 10 MPa. Temperature dependent binary interaction parameters (BIP) between the cyclohexane/asphaltene and toluene/asphaltene pseudo-component pairs were proposed to match the data. All other BIP were set to zero. The model with BIP determined from asphaltene precipitation in heavy oil and binary solvents predicted asphaltene precipitation from heavy oil and ternary solvent blends, generally to within the experimental error.

Development of a bioactive chitosan HPMC-based membrane with tea polyphenols encapsulated in β-cyclodextrin as an effective enhancement

Biodegradable membranes of chitosan and its composite with other natural polymers provide a promising solution for biomaterials. To further improve the antibacterial activities of chitosan (CS)/hydroxypropyl methyl cellulose (HPMC) membrane, natural extracts tea polyphenols (TP) were employed in this work. And TP was encapsulated by β-cyclodextrin (CD) beforehand to improve its compatibility with HPMC. To our knowledge, it’s the first time ever reported to use CD encapsulated TP in CS/HPMC membranes. And variety characterization results such as Fourier transform infrared spectroscopy (FTIR), ultraviolet spectra (UV) and dynamic light scattering (DLS) showed that TP had successfully encapsulated with CD. After the solvent blending of CS/HPMC and CDTP, CS/HPMC/CDTP membrane was prepared by a casting method and exhibited good toughness and tensile strength. Finally, bacterial inhibitive rate and inhibition zones of the membrane with E. coli and S. aureus proved the enhanced antibacterial as expected. And the morphology of the bacteria was observed to estimate the possible interaction approach of materials and bacteria. The novel biodegradable membrane can be used for antibacterial coating application.

Removing Acrylic Conformal Coating with Safer Solvents for Re-Manufacturing Electronics.

Conformal coating is typically composed of polymeric film and is used to protect delicate electronic components such as printed-circuit boards. Without removing conformal coating, it would be difficult to repair these complicated electronics. Methylene chloride, also called dichloromethane (DCM), has a widespread usage in conformal coating stripper products. The high toxicity of DCM increases human health risk when workers are exposed to DCM during the conformal coating removal processes. Therefore, the replacement of DCM would be beneficial to greatly improve the overall safety profile for workers in the electronics and coating industries. This research identified and evaluated alternative chemicals for replacing DCM used in acrylic conformal coating stripping operations. The solubility of an acrylic conformal coating was measured and characterized using Hansen solubility parameters (HSP) theory. Coating dwell time tests using various solvent blends verified the accuracy of the created HSP solubility sphere. A data processing method was also developed to identify and screen potential alternative solvent blends in terms of safety, toxicity, and cost-effectiveness. The identified safer solvent blends were demonstrated to provide equivalent stripping performance as compared to DCM based coating strippers within an acceptable cost range. The results of this research will be of value to other types of conformal coatings, such as silicone and polyurethane, where DCM is commonly used in similar coating stripping operations. By safely removing conformal coating, delicate electronics would be available for re-manufacturing, enabling a circular economy.

Modeling Aerosol Growth for a Solvent Blend

Management of aerosol in amine scrubbing requires the modeling of aerosol growth at the conditions of the absorber and water wash. If the amine aerosol grows well above 3 µm, it is collected through impaction on the packing and mist eliminator. Although aerosol models for single amine solvents have been developed, none have been reported for blended amine solvents. The presence of a second amine in the bulk liquid might affect the aerosol growth mechanism, composition, and size. Without a model for an amine blend, it is difficult to identify operating conditions that can grow the aerosol to larger sizes for mitigation. This work simulates aerosol growth for a proprietary solvent blend of amines AM1 and AM2. The model calculates the size and composition of a single aerosol drop traveling through the absorber and water wash. It tracks the water, CO2, AM1, and AM2 in the bulk gas phase and aerosol phase with mass transfer occurring at the bulk gas-drop interface and the bulk gas-solvent interface. The approach to modeling aerosol growth in the absorber and water wash involved two steps: (1) process modeling with ProTreat® and Aspen Plus® and (2) aerosol transport modeling with gPROMS®. The simulation was performed for two run conditions with 90% CO2 capture but different lean solvent and intercooling temperatures. The results show that the aerosol grows by picking up water, CO2, and AM1 in the absorber, and only water in the water wash. The aerosol grows to sizes well above 3 µm at the absorber mid-point, absorber outlet, and water wash outlet and will be easily collected. It grows fastest at cold zones in the absorber where the gas and aerosol are not in equilibrium. More packing and colder circulation water in the water wash were found to increase aerosol growth.