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BACKGROUND: The tetrahydrofuran–ethanol azeotrope cannot be separated by common distillation, but can be effectively separated by extractive distillation. Extractive distillation can be simulated by Aspen Plus software. The minimum annual cost of the process can be calculated to assess ionic liquid separation ability. The interaction energy can be used to explain the separation mechanism. RESULTS: The non‐random two‐liquid model parameters of ternary mixtures for tetrahydrofuran and ethanol containing tributylmethylammonium acetate or 1‐octyl‐3‐methylimidazolium acetate were obtained. Thermodynamic property databases of tributylmethylammonium acetate, 1‐hexyl‐2,3‐dimethylimidazolium acetate and 1‐octyl‐3‐methylimidazolium acetate were established. Based on the thermodynamic model parameters and properties, the sequential iterative method was used to determine the best operating conditions and minimum total annual cost the of extractive distillation process. The interaction energy was calculated to explain the separation mechanism. CONCLUSIONS: The separation performance of tributylmethylammonium acetate is better than that of 1‐hexyl‐2,3‐dimethylimidazolium acetate or 1‐octyl‐3‐methylimidazolium acetate. The selection and design of the ionic liquids can be conducted in terms of the interaction energy. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The chemical formula of basic zinc chloride is Zn5(OH)8Cl2 · H2O (denoted as ZHC). It is a new type of zinc source additive, widely used in the feed industry. In this article, micron‐sized hexagonal flake ZHC with a diameter of 10–60 µm is directly prepared by ammonia precipitation method using ZnCl2 as raw material. The products are characterized and analyzed by X‐ray diffraction, scanning electron microscopy, and laser particle size analyzer. The effects of reaction temperature, ammonia flow rate, aging time, and reactant concentration on the product morphology are studied. Under the optimum reaction conditions, the ZnCl2 concentration is 2.0 mol L−1, NH3 flow rate is 300 mL min−1, the reaction time is 1 h, the reaction temperature is 80 °C, and the aging time is 5 h. Lastly, the yield reaches 49.06%. The growth habit of ZHC is theoretically analyzed by the Morphology program. The calculation results are in good agreement with the experimental results. The change of (003) crystal plane exposure caused by temperature is an important reason for the non‐ideality of macroscopic morphology. [ABSTRACT FROM AUTHOR]

BACKGROUND: The binary benzene–n‐propanol azeotrope can be formed in chemical production. Extractive distillation is an important azeotrope separation technology and an ionic liquid is a type of excellent entrainer. Aspen Plus software was used to simulate the extractive distillation process. The separation performance of ionic liquids was evaluated in terms of total annual cost of the extractive distillation process. The separation mechanism of the azeotrope was quantitatively explained using intermolecular interaction energy. RESULTS: The thermodynamic properties databases of 1‐octyl‐3‐methylimidazolium acetate, trioctylmethylammonium acetate and 1‐decyl‐3‐methylimidazolium acetate were established in Aspen Plus software. The extractive distillation process was established through combining the thermodynamic properties of the three ionic liquids and the vapor–liquid equilibrium data of benzene–n‐propanol–ionic liquid. The optimal operating conditions were obtained by minimizing the total annual cost of the separation process through a sequential iterative method. The interaction energy was calculated using density functional theory through Gaussian 09 software and used to explain the principle of the benzene–n‐propanol azeotropic system separation. CONCLUSIONS: 1‐Octyl‐3‐methylimidazolium acetate has the best separation performance among the three ionic liquids. The interaction energy can be used to screen and design ionic liquids in the process of benzene–n‐propanol extractive distillation separation. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

In this study, traditional strongly endothermic anaerobic retorting (AR) and relatively novel self‐heating retorting (SHR) processes for oil shale (OS) were investigated and compared in detail. These studies mainly involve the structural and quantitative evolution of organic matters in OS during retorting, including varieties of crystallite parameters, carbon framework structure, amounts of various structural carbons and toxic polycyclic aromatic hydrocarbons, and so on. The obtained results well elucidate some reaction pathways in AR and SHR as well as certain differences between the two retorting processes. Moreover, based on our former work that verifies SHR greatly simplifies retorting operation by in situ generating heat to replace external heat carrier/provision, this study further demonstrates that SHR also alleviates the environmental effect of organic toxic residues as compared to AR. The present study provides some critical results not only for penetrating the reaction mechanism but also for assessing or controlling the environmental impact of both retorting processes. [ABSTRACT FROM AUTHOR]

Oil shale (OS) is a particularly promising alternative fossil fuel source. However, very different from coal, its inorganic mineral content is very high. The organic matters (mainly kerogen) are finely distributed in the inorganic minerals. Therefore, the minerals may affect the processing of OS, whose elucidation is critical to the choice of processing conditions. In this work, different minerals (SiO2, CaCO3, and Al2O3) were added to OS with different mass ratios of OS to mineral, respectively. Then, the thermogravimetric (TG) technique was employed to analyze the reaction behavior of these different OS/mineral mixtures in N2and in air for studying the influence of minerals on the OS pyrolysis in N2(i.e., retorting) and on the OS combustion in air. The results show that CaCO3and Al2O3have a promoting effect on both pyrolysis and combustion of OS, and they can decrease the reaction activation energy of both kinds of processes. However, SiO2has an inhibitive effect and can increase the reaction activation energy for both kinds of processes. It is hoped that the present study can further increase the understanding toward the effect of different minerals on the OS reactions. [ABSTRACT FROM PUBLISHER]

Multi-walled carbon nanotube (MWCNT)/polythiophene (PTh) composites have been prepared by in situ chemical oxidative polymerization. PTh is synthesized onto the sidewalls of the MWCNTs, which play a role as hard templates for PTh to produce one-dimensional nanostructures. The morphology and structures of the MWCNT/PTh composites are characterized by High-resolution transmission electron microscopy, x-ray diffraction, and Fourier transform infrared spectrometry. Their electrical property and thermal stability are determined using vector network analyzer and thermal gravimetric analyzer. Moreover, the mechanism of MWCNT/PTh nanowire formation is described. The studies show that the composites are nanowires with core-shell structure, in which the outer shells and inner cores are formed by PTh and MWCNTs, respectively. The addition of MWCNTs does not change the backbone structure of PTh and affect the amorphous condition of PTh very slightly, however, it improves the electrical conductivity and thermal stability of PTh. [ABSTRACT FROM AUTHOR]