With the growing emphasis on green chemistry and sustainable development, the resource utilization of waste salt has garnered significant attention. The production of soda ash from waste sodium sulfate presents a viable and sustainable pathway for the green transformation of the chemical industry. Current studies on this production method primarily focuses on single-factor effects on product purity, often overlooking the critical synergistic or antagonistic interactions between key process parameters. To address the aforementioned issues, this study systematically investigated the key factors and their interactions using response surface methodology. The process began with a pretreatment stage that effectively removed total organic carbon and color, while also adsorbing organic impurities such as heterocycles, anilines, ketones, phenols, and long-chain alkanes. For the soda ash synthesis via the double decomposition reaction of the pretreated waste sodium sulfate, single-factor experiments and response surface methodology optimization established the following optimal conditions: a reaction time of 1.96 h, a reaction temperature of 39 °C, and a material mass ratio of 1.284 (m (ammonium bicarbonate): m (sodium sulfate)). Under these conditions, the maximum soda ash purity of 99.35% was achieved. Furthermore, a binary regression model was developed for the process, with predictions showing excellent agreement with experimental data, confirming its reliability and practical utility. Additionally, the kinetics of the double decomposition reaction were determined by fitting a pseudo-second-order kinetic model in combination with the Arrhenius equation, and the resulting expression is as follows.1/tlnβ0−Xβ01−X−βX/t=exp−69475/RT+4.3637×10−16. Through this waste-salt valorization pathway, not only can the accumulation of industrial waste sodium sulfate and associated environmental pollution risks be effectively reduced, the production cost per ton of sodium carbonate can be reduced by approximately 600 RMB, yielding significant sustainable economic benefits and providing strong support for advancing a green and low-carbon economy.

Dimethylphenols serve as important intermediates in synthesizing pharmaceuticals and agrochemicals, yet traditional distillation struggles to separate their isomers due to minimal boiling point differences, and the development of melt crystallization is hampered by lacking solid-liquid equilibrium (SLE) data for some isomers. Therefore, the SLE data of both binary and ternary mixtures of 2,3-dimethylphenol (2,3-DMP), 3,5-dimethylphenol (3,5-DMP), and 3,4-dimethylphenol (3,4-DMP) were determined by using differential scanning calorimetry in this work. Additionally, crystallographic analysis was conducted to investigate the thermodynamic characteristics of these mixtures. The experimental results indicated that all the systems investigated in this research exhibited eutectic behavior. The experimentally obtained SLE data were well correlated with the Wilson and non-random two-liquid models. The excess thermodynamic functions were calculated to analyze the types and intensities of the molecular interactions occurring in the mixtures. Furthermore, this study developed a model for the correlation between the theoretical crystallization yield and the actual cooling yield and final yield in melt crystallization. This study has furnished reliable data essential for developing and optimizing the melt crystallization process of mixtures of 2,3-DMP, 3,5-DMP, and 3,4-DMP. (c) 2025 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Methyl diphenylmethane dicarbamate (MDC) was synthesized by condensation of methyl phenylcarbamate (MPC) using trioxane as methylenation reagents over sulfonic acid resin catalyst. The effect of Brønsted's acid amount on the condensation reaction was investigated, and the optimal sulfonic acid resin (NKC-9) with an acid amount of 4.57 was determined. 2-MDC, featuring a methylene-bridged biphenyl structure, achieved 91.6% selectivity and 83.2% yield after response surface methodology optimization. In situ FTIR spectroscopy was employed to monitor the condensation process. The spectroscopic results unequivocally demonstrate that trioxane undergoes catalytic depolymerization to formaldehyde over NKC-9 resin, which subsequently reacts with MPC to form MDC. After sulfuric acid regeneration, NKC-9 maintains its catalytic performance after 4 cycles.

This work investigates the bubble breakup process with and without particles in turbulent conditions using the image-based method. A binocular high-speed camera was employed to capture breakup events. A deep learning-based image identification software (Large Deformation Dispersed Phase Analysis in Multiphase Flows) and a highly deformed bubble volume/surface area quantification method (Dense Adaptive Segmentation Method) are proposed. An energy barrier is found during the bubble breakup process, with the maximum increase in surface area (Delta Smax) being two to three times the final increase after breakup (Delta Sfinal). This indicates that the critical energy required for bubble breakup is underestimated in most breakup models. The presence of suspended particles raises this energy barrier, thus reducing the breakup probability. The daughter bubble size distribution follows an M-type distribution in water, while the addition of particles leads to a tendency towards equal-size breakup. This work provides a reliable technology and the experimental data for further clarifying the bubble breakup mechanism.

Dimethyl hexane-1,6-dicarbamate (HDC), the vital intermediate for nonphosgene production of hexamethylene-diisocyanate (HDI), was effectively synthesized via carbonylation of 1,6-hexanediamine (HDA) using methyl carbamate (MC) as a carbonyl source over a silanol-rich MCM-41 catalyst. The effects of reaction conditions, including the reaction temperature, molar ratio of raw materials, methanol dosage, catalyst dosage, and reaction time, on the HDC yield were evaluated. Under the reaction conditions with a reaction temperature of 190 °C, a molar ratio of HDA, MC, and methanol of 1:6:50, a catalyst dosage of 10 wt %, and a reaction time of 3 h, the yield of HDC can reach as high as 92.6% with 100% HDA converted. Characterizations based on N2 physical adsorption/desorption, scanning electron microscopy (SEM), X-ray diffractometry (XRD), NH3-temperature-programmed desorption (TPD), Fourier transform infrared spectroscopy (FTIR), and 1H magic-angle spinning (MAS) NMR indicated that the abundance of silanol groups on the surface of MCM-41 probably resulted in the good performance of MCM-41. After five cycles of MCM-41, the HDC yield decreased from 92.6 to 67.9%, probably due to the loss of surface silanol groups and the carbon deposition on the catalyst as well as the particle agglomeration. The study on the substrate scope suggested that MCM-41 shows good-to-excellent catalytic performance in the synthesis of a variety of aliphatic and alicyclic dicarbamates.

《物理化学》是一门面向工科专业开设的学科基础必修课，是化工、材料、环境等工科专业各门理论课程的基础，课程内容复杂、公式概念多、不易理解。针对课程理论性强、抽象难学的特点，本文设计了串联知识模块、注重工程背景、融入课程思政、线上结合线下的教学思路，力求激发学生的学习兴趣，培养学生的科学思维和家国情怀，力求使课程能够适应新工科建设背景。

Photocatalytic degradation is a very eco-friendly technology, which provides a new way for the degradation of many organic pollutants. A comprehensive experiment on the degradation of ethyl xanthate by titanium dioxide/activated carbon photocatalyst is designed to address the bottleneck issue of organic pesticide residues in tailings and tailings wastewater that are difficult to treat, including preparation of titanium dioxide / activated carbon, determination of xanthate concentration, photocatalytic degradation experiment and recycling of composite photocatalyst. The experimental results show that activated carbon can load titanium dioxide well. The optimum calcination temperature of titanium dioxide / activated carbon photocatalyst is 500 ℃, and the optimum doping ratio of activated carbon is 20%. The teaching experiment involves physical chemistry, material chemistry, instrumental analysis and other curriculum knowledge, which is helpful to train students' experimental operation ability and cultivate their creative thinking.

The carbonylation of 1,6-hexanediamine (HDA) is an important method for the production of dimethyl hexane-1,6-dicarbamate (HDC), which is of great significance for the non-phosgene synthesis of hexamethylene-diisocyanate. This research focuses on the synthesis of HDC through the methoxycarbonylation of HDA using methyl carbamate as a carbonyl source. The study investigates the utilization of CeO2 catalyst prepared via H2O2assisted precipitation. Various characterization techniques, including N2 physical adsorption and desorption, SEM, TEM, XRD, NH3TPD, CO2TPD, and XPS are employed to analyze the texture and structure of CeO2 catalysts prepared through different methods. In situ FTIR experiments are conducted to monitor the potential process of the carbonylation reaction. The results of the in situ FTIR spectroscopy clearly indicate the formation of polyurea as an intermediate compound, which subsequently converts into HDC. The findings demonstrate that CeO2 prepared using the hydrogen peroxide precipitation method exhibits a larger specific surface area, stronger acid-base properties, and a higher content of surface-adsorbed oxygen. These characteristics are favorable for the carbonylation reaction. Under optimized conditions, the HDC yield reaches 96.0% with complete conversion of HDA. The catalyst's activity essentially maintained throughout ten cycles. Additionally, a substrate versatility study reveals that CeO2 exhibits excellent catalytic properties for synthesizing a range of aliphatic and alicyclic dicarbamates.

TiO 2 is a semiconductor material with excellent photocatalytic activity, good stability, and low cost. However, it has some disadvantages,such as a large band gap and easy recombination of electron-generating holes. Biochar is a carrier material with excellent performance because of its loose and porous structure, large specific surface area, rich surface functional groups, and easy modification. The TiO 2 /biochar composite exhibits advantages such as good visible light response, excellent electron transport capacity, strong adsorption capacity, and less electron-hole recombination,which has a broad application prospect in water pollution treatment. This paper reviews the preparation and modification methods of TiO 2 /biochar composites, expounds on the synergistic effect and photocatalytic mechanism of the composites, summarizes the current application of TiO 2 /biochar composites in the treatment of different pollutants, and the development prospect and direction of TiO 2 /biochar composites have prospected.

利用装填有CaY分子筛的固定床对乙二醇和1,2-丁二醇吸附分离进行研究,从水、甲醇、乙醇和正丙醇中筛选出正丙醇为最佳洗脱溶剂,并探究了进样流速(0.4,0.8,1.2mL/min)及操作温度(298,318,338 K)对穿透曲线的影响,对测得的穿透曲线采用Modified Dose-Response模型进行拟合,与实验结果能够高度吻合.并采用巨正则蒙特卡洛(GCMC)研究混合醇在CaY分子筛内部的竞争吸附,模拟了乙二醇和1,2-丁二醇在CaY分子筛内部的吸附位点,发现其吸附位点几乎重合,且CaY分子筛对乙二醇的吸附量要大于1,2-丁二醇,此模拟结果为实验结果提供了微观理论支撑.

化工热力学是化学化工类专业的必修课,在专业人才培养中发挥着重要作用,但课程内容原理性强、学习难度大、蕴含思政元素少.本文以基于学习产出的教育理念为指导,挖掘每一章节内容中蕴涵的思政元素,探索化工热力学思政教学的设计方法,并以流体p-V-T关系相关内容为例,展示化工热力学课程思政的教学实践.结果表明:化工热力学与课程思政两者可以很好地融合,通过思政元素的挖掘和依托知识点的选择,可以产生良好的教学效果;学生对于课程思政的学习都表现出积极的态度.借助课程思政教学,可以提高学生们的学习热情和专业认同感.

Carbonylation of m-xylylene diamine (XDA) with ethyl carbamate to produce m-xylylene dicarbamate (XDC), which is the crucial intermediate for the production of m-xylylene diisocyanate (XDI), over the hierarchical TS-1 (HTS-1) zeolite catalyst was studied. The catalysts were characterized by Brunauer-Emmett-Teller, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and temperature-programed desorption of ammonia techniques systematically. The results showed that the high performance of HTS-1 could be attributed to the weak acidity and high V meso/V total ratio of the catalyst. Impacts of reaction time and reusage on the HTS-1 catalyst were also investigated. Under 6 h and 200 °C, XDA conversion could reach 100% with 88.5% XDC yield. Furthermore, partial loss of Ti active sites with Lewis acidity on the catalyst surface led to the decrease of XDC yield during recycling. Moreover, a possible reaction mechanism for the title reaction was primarily proposed.

The effect of polyethylene glycol (PEG) with different molecular weights on carbamazepine (CBZ) crystallization was investigated by experiments and molecular dynamics (MD) simulations. The influence of PEG on the crystal morphology and solvent-mediated phase transition of CBZ was studied. It was found that PEG inhibited the CBZ III nucleation and CBZ II transition. The crystal morphology changes significantly from needle to rod when adding PEG with a molecular weight greater than 1500. MD simulations show that the binding energy sequence between the additive and the crystal surface is: Eb(1 -1 -1) > Eb(2 -2 1) > Eb(2 -1 0), which explains the suppression of axial crystal growth. The results provide a possible method to stabilize the metastable crystal form of CBZ and improve crystal morphology.

基于传统化工原理实验教学过程中存在的主要问题,提出了结合仿真平台、课前自讲、实验操作和报告撰写+考试的"四位一体"教学模式.通过课前的仿真练习和测验强化预习效果和安全意识,引入课前自讲环节强化课堂上学生的参与程度和生师互动,加强教学团队建设实现差异化考评,构建完善的考核制度强化过程考核."四位一体"教学模式更加切合工程教育专业认证以学生为中心、产出导向和持续改进的理念,有利于推动构建重能力、强创新、差异化的人才培养体系.

During utilization of high silicon solid wastes, a characteristic and complex desilication solution (DSS) generated, remains an important subject to be as precursor of calcium silicate hydrate (C-S-H) crystallization. By using the mixed suspension mixed product removal (MSMPR) crystallizer, the crystallization behavior of C-S-H in DSS was investigated. The effects of temperature, initial Ca/Si ratio, silicate concentrations, solvent alkalinity on the morphology and structure of synthesized C-S-H were investigated through X-ray diffraction, scanning electron microscopy, laser particle size analyzer, and 29Si magic angle spinning nuclear magnetic resonance. The crystallization growth rate and particle size of C-S-H were positively correlated with temperature. The elevation of Ca/Si molar ratio will lead to shortening of the silicate chain to form more monomers. The increase of silicate concentration and solvent alkalinity will result in the formation of shorter silicate chains. This work provides theoretical guidance for precise preparation and design of C-S-H synthesized by a causticization strategy.

黄药是硫化矿和氧化矿等浮选作业中广泛应用的一种捕收剂.有色金属选矿废水中的残留黄药对生态环境存在极大危害,有效处理后可回用于浮选作业,节约成本,并减小对环境的污染风险,具有重要现实意义.本文简述了目前选矿废水中残留黄药的处理方法及研究进展,总结了现有方法的优缺点并提出展望,为实现选矿废水中黄药的绿色高效处理提供重要参考.

在"新工科"建设背景下,传统化工专业面临新的形势与挑战.文章基于学科交叉融合视角,针对行业高校化工专业的特点,从优化重组课程体系、融入课程思政元素、完善实践教学体系、整合创新教学环节、开设国际化课程组等方面进行了阐述.

我国土壤铬(Cr)污染的形势较为严峻,目前对重金属Cr(Ⅵ)的治理迫在眉睫.本文通过对铬污染的来源、修复机理、形态转化与毒性危害进行阐述,论述了目前多种常见的土壤重金属铬污染修复技术,通过分析各方法的运用实例与实验室试验结果,指出土壤铬污染的主要问题以及传统方法、新型方法和联合修复方法的发展与前景.相比而言,一些新型修复方法和联合修复可避免单一修复的不足之处,其修复效果较好、经济效益高、产生的不利影响较小.

间苯二亚甲基二氨基甲酸酯(XDC)是非光气绿色合成特种异氰酸酯间苯二亚甲基二异氰酸酯(XDI)的关键中间体.本工作以TiO2作为催化剂,以尿素、间苯二甲胺(XDA)和乙醇为原料绿色高效合成XDC.通过气质联用,分析了 XDC合成的主副反应,推测了主反应路径,并优化了反应工艺条件.结果表明,以TiO2作为催化剂时,催化剂用量为0.2g,即约为15wt％XDA,乙醇用量为0.2mol,n(urea):n(XDA)=3:1,反应温度为205℃,反应时间为6h时,XDA转化率为100％,XDC收率可达82.4％.本研究提供了 XDC绿色高效的合成方法.

化工热力学概念杂、公式难、模型多,使学生感到枯燥乏味,毫无兴趣.将Aspen Plus软件融入到教学过程中是增强学生理解的有效手段之一.然而学生使用Aspen Plus软件时,极易忽略依据化工热力学的所学内容选择物性方法,往往通过不断地尝试从而确定可用的物性方法,这不仅违背了引入Aspen Plus软件的初衷,还助长学生浮躁的学习习惯.