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•Important properties of ChCl-PG 1:3 as extraction solvent were determined.•Efficiency of model fuel denitrification over 70% was achieved using ChCl-PG 1:3.•ChCl-PG 1:3 showed ...potential for removing N-compounds from real gasoline.•DES was regenerated by evaporating the extracted components between stages.•LLE in three-component systems were described by UNIQUAC activity coefficient model.
The use of deep eutectic solvents (DES) as “green” solvents could solve at least some of the environmental problems associated with the chemical and petrochemical industry. This paper investigates the applicability of DES made of choline chloride and propylene glycol in a molar ratio of 1:3 for the removal of sulfur and nitrogen compounds from hydrocarbon mixtures. Extraction experiments were performed in quasi-three-component systems, quasi-seven-component model systems and real fuel systems. All the experiments confirmed better solubility of pyridine (compared to thiophene) and nitrogen compounds (compared to sulfur ones) in the investigated DES, indicating its potential use as a denitrification agent. The basic application physico-chemical properties of the investigated DES were determined. Its applicability in multistage extraction processes was confirmed, its extraction capacity was determined and the ability of its regeneration by evaporation was demonstrated. Liquid–liquid equilibria in investigated quasi-three-component systems were described successfully by UNIQUAC activity coefficient model.
Research on plastic pollution has recently evidenced the ubiquitous presence of tiny plastic particles called microplastics. Microplastics alter organisms because microplastics tend to bioaccumulate, ...they contain hazardous additives, and they carry other contaminants and pathogens adsorbed on their surface. Here, we review the biodegradation of the five most common microplastics: polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, and polystyrene. Despite the fact that most plastics are hardly biodegradable, biodegradation is still a popular remediation techniques because it is highly economical and environmentally friendly. Biodegradation can be done applying single or combined bio-cultures such as bacteria, mold, yeast, and algae. We present analytical and microbiological methods used for monitoring microplastic biodegradation. Actually, no microbial method removes completely microplastics from the environment within a reasonable time interval. As a consequence, the last developments combine biodegradation with other methods such as membrane filtration.
In an attempt to develop alternative methods that meet the criteria of ‘green’ technology in gasoline production, choline chloride and ethylene glycol (ChCl-EG) based deep eutectic solvents (DESs) in ...molar ratios of 1:2, 1:3 and 1:3.5 were tested for desulfurization, denitrification and dearomatization of model and real gasoline. Using ChCl-EG 1:3.5 denitrification efficiency of 70.9% with respect to pyridine was achieved in a single extraction stage; efficiency above 99% was obtained in four stages. The DESs were regenerated by evaporating extracted components between stages, allowing for its multiple use. The equilibrium phase compositions in model fuel experiments were fairly predicted by UNIQUAC model. Physical properties of DESs important for application as extraction solvents were determined, too. The extraction data collected on real fuels shown that only the loose qualitative correlation with the model fuel experiments can be established.
Ovaj dokument definira nazive povezane sa svojstvima pojedinačnih makromolekula, makromolekulskih nakupina, polimernih otopina i amorfnih polimernih tvari. U odjeljku o polimernim otopinama i ...amorfnim polimernim tvarima razmatraju se opće i termodinamičko nazivlje, razrijeđene otopine, fazno ponašanje, transportna svojstva, metode raspršenja svjetlosti i separacijske metode. Preporuke su revizija i proširenje nazivlja IUPAC-a objavljenog 1989., koje se ticalo pojedinačnih makromolekula, makromolekulskih nakupina i razrijeđenih polimernih otopina. Uvedeni su novi nazivi koji pokrivaju glavna teorijska i eksperimentalna saznanja do kojih se u međuvremenu došlo. Polielektroliti nisu uključeni.
The aim of this work was to develop a simple and easy-to-apply model to predict the pH values of deep eutectic solvents (DESs) over a wide range of pH values that can be used in daily work. For this ...purpose, the pH values of 38 different DESs were measured (ranging from 0.36 to 9.31) and mathematically interpreted. To develop mathematical models, DESs were first numerically described using σ profiles generated with the COSMOtherm software. After the DESs’ description, the following models were used: (i) multiple linear regression (MLR), (ii) piecewise linear regression (PLR), and (iii) artificial neural networks (ANNs) to link the experimental values with the descriptors. Both PLR and ANN were found to be applicable to predict the pH values of DESs with a very high goodness of fit (R2independent validation > 0.8600). Due to the good mathematical correlation of the experimental and predicted values, the σ profile generated with COSMOtherm could be used as a DES molecular descriptor for the prediction of their pH values.
•LLE for C5mimTf2N – (pyridine or thiophene) – hydrocarbon were determined.•The equilibrium data were well described with NRTL and UNIQUAC models.•Equilibrium in the seven-component systems was ...successfully predicted.•C5mimTf2N has potential for denitrification of real refinery FCC gasoline.
Liquid–liquid equilibria for the three-component systems with ionic liquid C5mimTf2N – (pyridine or thiophene) – hydrocarbon (toluene or n-hexane or n-heptane or i-octane) were determined at T=298.15K and atmospheric pressure. In addition, the applicability of C5mimTf2N as selective solvent for desulfurization, denitrification and dearomatization of a model six-component hydrocarbon solution as well as real refinery FCC gasoline was investigated on the laboratory scale. The equilibrium data in three-component and seven-component (model solution+ionic liquid) systems were well described with NRTL and UNIQUAC models. The suitability of ionic liquid for extractive desulfurization and denitrification was evaluated in terms of solute distribution ratio and selectivity, as well as extraction effectiveness.
Liquid-liquid equilibrium for eight ternary systems involving one hydrocarbon (from a series involving aliphatics n-hexane, n-heptane, i-octane or aromatics toluene) one solute (thiophene or ...pyridine) and an ionic liquid (IL, 1-benzyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) was experimentally measured at atmospheric pressure and 25 °C. Equilibrium data are presented qualitatively, with solubility curves and quantitatively, with tie lines. The appropriateness of IL for extractive desulfurization, denitrification and dearomatization was evaluated with respect to solute distribution ratio, selectivity and efficiency of IL. Extraction experiments with seven-component systems model solutions and real refinery FCC gasoline have been performed. The equilibrium data were used for the calculation of interaction parameters of NRTL and UNIQUAC activity coefficient models.
•Experimental LLE for bzmimTf2N – (pyridine or thiophene) – hydrocarbon.•LLE representing by NRTL and UNIQUAC.•Prediction of LLE in the seven-component systems.•bzmimTf2N has a potential for denitrification and dearomatization of FCC gasoline.
•The firing temperature of sewage sludge ash (SSA) affects the brick properties.•The best results were obtained with mixed-in SSA fired at 900 °C.•The soluble salts level rises with SSA addition but ...remains within allowed limits.•Higher firing temperatures reduce the soluble salts level in the bricks.
The influence of combustion temperature on the properties of sewage sludge ash (SSA) as a substitute material for the production of fired clay bricks was studied. The experiments were performed with sewage sludge (SS) from wastewater treatment plants (WWTP) in Zagreb (ZG) and Karlovac (KA). SS samples were fired at temperatures of 800, 900 and 1000 °C, and the properties of the resulting SSA were determined and compared with clay and SS. Bricks with 5 wt% SSA as clay substitute were prepared and compared with clay bricks (control). SSA bricks produced at higher temperatures are of higher strengths and lower water absorption, which are both desirable properties. Compressive strength tests showed that SSA obtained at a firing temperature of 900 °C is the most suitable for use in bricks. For the first time, the influence of SSA on the content of soluble salts in bricks was tested. The content of soluble salts, expressed by the electrical conductivity of leachate, in SSA bricks showed increased values compared to the control bricks, which were 2.8 and 4.6 times higher in bricks with SSA produced at 800 °C. Still, bricks with SSA prepared at higher temperatures had lower content of soluble salts and also SSA from KA had lower soluble salts content than SSA from ZG. The total amount of Na+, K+, Mg2+ in all bricks made with SSA was below the limits for category S2 according to EN 771-1.
Information on drug equilibrium solubility is crucial in producing a stable drug product, prolonging its shelf-life and maintaining its reported properties. Such data regarding the antipsychotic drug ...lurasidone hydrochloride (LRS HCl), were non-existent up to this date. We have presented results that could facilitate the formation of stable LRS HCl solid dispersions using amorphous poly(vinyl-pyrrolidone) (PVP) as a carrier.
For the purpose of drug solubility enhancement, solid dispersions with different drug loads were prepared by solvent evaporation method and characterized by thermogravimetric analysis, differential scanning calorimetry, and Fourier-transform infrared spectroscopy (FT-IR). Thermal analysis has been used to detect the changes in heat capacity (c
p
) occuring upon formation of a binary drug-polymer solid dispersion. Thermodynamic model accounting for those c
p
changes is used to estimate the Gibbs free energy of mixing (G
M
) and thus the equilibrium solubility of LRS HCl in PVP solid dispersions.
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