SPU-W 分子筛催化异丙醇制备异丙醚参数优化的研究

以SPU-W分子筛为催化剂,研究了异丙醇脱水反应制备异丙醚的工艺条件,考察了硅铝比、反应温度以及分子筛用量对SPU-W分子筛催化异丙醇脱水反应的影响,并利用扫描电子显微镜(SEM)对催化剂进行表征。研究结果表明:硅铝比为25的SPU-W分子筛的催化效果最好, SPU-W分子筛催化异丙醇制备异丙醚的最佳反应温度和最佳用量分别为180℃、0.5 g,在此条件下,异丙醇的转化率为42.72%,异丙醚的选择性为87.08%。     

汽车前挡玻璃黏结支架脱落行为研究

针对3个制件（西南区域失效件：重庆件;华南失效件：广州惠州件和正常人为破坏件）分别使用傅里叶红外光谱仪、超景深显微镜和扫描电子显微镜3种仪器对它们进行观察并作对比分析,同时也分析了清洁溶剂异丙醇对支架的影响。结果表明,清洁溶剂异丙醇对支架的影响极小;,2个失效件的底涂部位和脱胶部位有不同程度的缺陷和裂纹,说明黏结部位的界面结合力降低是支架脱落的直接原因;底涂的厚度对支架的界面结合力有较大的影响。     

Simulated annealing-based optimal design of energy efficient ternary extractive dividing wall distillation process for separating benzene-isopropanol-water mixtures

This article investigates the performances of different extractive distillation processes intensified with dividing-wall column for separating benzene-isopropanol-water ternary mixtures. All the processes with ethylene glycol as solvent are optimized with the minimal total annual cost (TAC) as target. In order to get the global optimal solution intelligently, an improved simulated annealing algorithm is adopted, which is programmed in MATLAB and linked to Aspen Plus. The results show that the extractive dividing wall column-solvent (EDWC-S) process consisting of an extractive dividing wall column and a solvent recovery column is the best scheme. It can reduce the TAC by 28.65％and CO2 emissions by 32.84％com-pared to the conventional triple-column extractive distillation process.     

Dehydration of C2–C4 alcohol/water mixtures via electrostatically enhanced graphene oxide laminar membranes

The dehydration of alcohol/water mixtures using pervaporation membranes requires less energy than is required by conventional separation technologies. In this paper, we report electrostatically enhanced graphene oxide (GO) membranes for the highly efficient pervaporation dehydration of C₂–C₄ alcohol/water mixtures. Positively charged molecules were introduced as the interlayer of negatively charged GO layers via layer-by-layer assembly, thereby creating an electrostatic attraction that drives the assembly of GO nanosheets into ordered interlayer channels. The effects of the feed temperature, water concentration, and continuous operation on the membrane transport behavior were systematically investigated. In the dehydration of 90 wt% alcohol/water mixtures at 70°C, the membrane exhibited ethanol/water, isopropanol/water, and n-butanol/water fluxes of 2.35, 2.98, and 4.69 kg/(m² hr), respectively, as well as separation factors for the same mixtures of 3,390, 5,790, and 4,680, respectively. This excellent alcohol/water dehydration performance outperforms those of state-of-the-art polymeric membranes and GO-based membranes.     

Three extraction methods for determination of lipids in fish meal: Evaluation of a hexane/isopropanol method as an alternative to chloroform-based methods

Three different extraction methods were compared for the determination of lipids in both oxidised and antioxidant-stabilised brown fish meal. The three methods under investigation were those of Smith-Ambrose-Knobl using chloroform/methanol/water, Bligh and Dyer also using chloroform/methanol/water but monophasic, and Hara and Radin using hexane/isopropanol. The fat content, determined gravimetrically, was significantly lower (P < 0.05) when hexane/isopropanol was used for lipid extraction from both oxidised and antioxidant-stabilised fish meal, than when either of the chloroform systems was used. Determination of lipid classes in the lipid extracts using silica gel thin-layer chromatography on Chromarods-SIII, with flame ionisation detection by latroscan, suggested that the lower lipid recovery by the hexane/isopropanol method may be due to a less effective extraction of the more polar lipid classes. including oxidation products, present in brown fish meal.     

丙酮一步法生产MIBK装置的副产物精馏分离研究

针对丙酮一步法生产MIBK装置的副产物(丙酮、异丙醇、水、MIBK混合物),采用间歇精馏分离得到纯度大于98%的丙酮、纯度大于99%的异丙醇和水恒沸物、纯度大于90%的MIBK。对分离得到的纯度大于99%的异丙醇和水恒沸物用乙二醇作为萃取剂进行萃取精馏分离得到纯度99.5%异丙醇,同时减压精馏回收乙二醇。     

液膜反应器中异丙醇脱氢性能及反应动力学

研究了反应物进料速度、催化剂用量和反应温度对以非晶态合金雷尼镍为催化剂的液膜多相反应模式下异丙醇脱氢反应的影响,考察了反应动力学. 结果表明,温度的影响最显著,与搅拌釜液相脱氢相比,该反应模式有效提升了产氢速率,Langmuir?Hinshelwood反应动力学表达式计算结果与实验结果吻合良好.     

极性界面对海藻酸钙凝胶单元形态与降解性能的影响

生物支架的降解直接影响其结构、功能及所装载细胞的存活率.以海藻酸钠为原料,氯化钙为交联剂,制备海藻酸钙水凝胶生物支架;通过交联剂溶剂中异丙醇(IPA)与去离子水(DWⅣ)比例的变化,获得不同极性条件的同轴反应流界面,从而影响海藻酸钙凝胶的凝胶单元聚集形态,考察界面极性对其降解进程的调控能力.结果 表明,随着交联剂中IP...     

锂电池负极材料四氧化三钴的结构优化及其电化学性能研究

以异丙醇作为溶剂,通过溶剂热法在不同反应时间下制备了前驱体碳酸钴,再采用高温煅烧法制备了超细纳米/微米多孔四氧化三钴粉末,研究了反应时间对前驱体碳酸钴及四氧化三钴的组成及形貌的影响,并测定了四氧化三钴负极材料电化学性能.结果表明,纳米/微米球(2～4μm)由细小且均匀的四氧化三钴纳米颗粒和孔洞组成;以四氧化三钴作为锂离...     

异丙醇生产副产物中异丙醚的分离精制技术

采用萃取精馏和共沸精馏的试验方法,从异丙醇装置副产品中分离精制异丙醚．结果表明,以甘油为萃取剂,甲醇为夹带荆,可分别得到质量分数大于99％的异丙醚和质量分数大于99．5％的异丙醇,异丙醚收率为70．35％,具有明显的经济效益。