白酒中氨基甲酸乙酯检测方法比较

建立并使用了高效液相色谱法(HPLC)与气相色谱-质谱联用法(GC-MS)两种白酒样品中EC的检测方法,两种方法定量分析的线性关系良好,相关系数在0.997以上。其中HPLC法检出限为4.0μg/L,回收率在84.9%~105.1%之间,RSD<6.84%;GC-MS法检出限为1.3μg/L,GC-MS检测回收率在95.3%~104.7%之间,RSD<4.26%。结果显示,两种方法的准确性和重复性均符合实验要求。其中HPLC法具有前处理操作方便,且试剂毒性相对较低的优点,但GC-MS方法的精确性和稳定性则比HPLC法更高,且检出限更低、总体处理及进样时间更短,单位时间内能更快、更精确地对酒样中氨基甲酸乙酯进行检测。结合产业实际发展情况,白酒的氨基甲酸乙酯检测量日益增多,检测限要求更低,故使用GC-MS法检测白酒中的氨基甲酸乙酯更能满足今后的检测工作需求。     

超声微波耦合制备P(AM-DMC-BA)及其污泥脱水研究

以丙烯酰胺(AM)为主单体、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为阳离子单体、丙烯酸丁酯(BA)为疏水单体,偶氮二异丁脒盐酸盐(V-50)为引发剂,通过微波和超声耦合技术合成新型高效阳离子共聚物絮凝剂P(AM-DMC-BA)。考察了原料对P(AM-DMC-BA)特性黏度及转化率的影响,P(AM-DMC-BA)对其进行了表征,并用于污泥脱水实验。结果表明,当单体AM、DMC、BA的质量分数分别为22.5%、7.5%、1%,引发剂V-50的质量分数为2%,尿素的质量分数为1.2%,聚合体系pH为3.5,制得的P(AM-DMC-BA)的特性黏度及转化率最高。当共聚物投加量为45 mg/L、污泥溶液pH为7时,其对污泥有较好的脱水性能,且具有良好的pH抗性。     

新型氨基甲酸乙酯人工抗原的制备与表征

目的合成新型氨基甲酸乙酯(ethylcarbamate,EC)人工抗原并对其效果进行表征分析。方法用4-(二苯基羟甲基)苯甲酸对EC衍生化合成半抗原,用核磁氢谱(proton nuclear magnetic resonance, NMR)、核磁碳谱和质谱法(massspectrometry,MS)对其结构进行表征;用活化酯法将EC半抗原与牛血清蛋白(bovine serum albumin, BSA)偶联得到EC人工抗原。用紫外光谱和荧光光谱法对人工抗原进行表征并计算偶联比,用考马斯亮蓝法测定蛋白含量,间接竞争酶联免疫法鉴定其免疫活性。结果 EC半抗原结构与理论结构一致,半抗原与BSA成功偶联,偶联比为13:1,冻干粉的蛋白含量为0.695 mg/mg,用该新型人工抗原免疫小鼠,得到的抗血清效价为1:10000,且特异性较好。结论该新型氨基甲酸乙酯半抗原具有较好的免疫活性。     

月桂酸乙酯的液相音速测量

脂肪酸甲酯(FAMEs)、脂肪酸乙酯(FAEEs)是生物柴油中的重要成分,为了计算发动机燃油喷射角度,需要获取生物柴油组分的音速。利用动态光散射法,在0.1、2.0、4.0、6.0、8.0 MPa下测量了月桂酸乙酯的液相音速,温度为295.15～353.15 K。为满足工程应用需求,根据实验数据,给出了月桂酸乙酯音速与温度和压力的关联式。在实验温、压范围内,实验值与关联式计算值的相对偏差绝对平均值为0.32%。     

Comparison of co-current and counter-current flow in a bifunctional reactor containing ammonia synthesis and 2-butanol dehydrogenation to MEK

In this study, a multi-tubular thermally coupled packed bed reactor in which simultaneous production of ammonia and methyl ethyl ketone (MEK) takes place is simulated. The simulation results are presented in two co-current and counter-current flow modes. Based on this new configuration, the released heat from the ammonia synthesis reaction as an extremely exothermic reaction in the inner tube is employed to supply the required heat for the endothermic 2-butanol dehydrogenation reaction in the outer tube. On the other hand, MEK and hydrogen are produced by the dehydrogenation reaction of 2-butanol in the endothermic side, and the produced hydrogen is used to supply a part of the ammonia synthesis feed in the exothermic side. Thus, 30.72% and 31.88% of the required hydrogen for the ammonia synthesis are provided by the dehydrogenation reaction in the co-current and counter-current configurations, respectively. Also, according to the thermal coupling, the required cooler and furnace for the ammonia synthesis and 2-butanol dehydrogenation conventional plants are eliminated, respectively. As a result, operational costs, energy consumption and furnace emissions are considerably decreased. Finally, a sensitivity analysis and optimization are applied to study the effect of the main process parameters variation on the system performance and obtain the minimum hydrogen make-up flow rate, respectively.     

酯交换法合成碳酸甲乙酯催化剂的研究进展

碳酸甲乙酯（EMC）是一种环境友好型的不对称碳酸酯，因其独特的结构性质被广泛用作溶剂或有机合成中间体，特别是随着锂离子电池的迅猛发展，其作为电池电解液主要成分市场需求量急增。文中简单介绍了光气法、氧化羰化法和酯交换法合成碳酸甲乙酯的研究进展。重点针对最具发展前景的酯交换法合成EMC工艺路线中所用催化剂进行了综述；讨论和分析了该路线所用催化剂的类型、结构、性质及性能，并对当前研究中存在的问题进行了归纳和分析总结。最后本文分析并展望了酯交换法合成EMC催化剂的研究方向及新型合成工艺发展趋势，提出研发经济、高效、稳定且制备工艺简单的非均相催化剂，并与反应精馏技术耦合是今后的主要发展趋势，期望为EMC的高效合成提供参考和借鉴。     

甲乙酮装置剩余丁烯的循环利用

对甲乙酮装置剩余丁烯的循环利用进行了研究,采用聚结器脱水-净化的方法,脱除了剩余丁烯中的仲丁醇、仲丁醚、甲乙酮和水分等杂质,使得剩余丁烯得到了循环使用,满足了水合工段的进料要求,同时提高了甲乙酮的产品质量。     

Combination of nuclear magnetic resonance spectroscopy and nonlinear methods to analyze the copolymerization of phosphonic acid derivatives

We demonstrate in this study that the combination of modern inline monitoring methods [here: inline nuclear magnetic resonance (NMR)] with simulations gains more exact and profound kinetic results than previously used methods like linearization without that combination. The ¹H-NMR spectroscopic data (more than 100 data points) are used to construct the copolymerization diagram. The reactivity ratios are obtained applying the van Herks nonlinear least square method. The examination of the radical copolymerization of 2-hydroxyethyl methacrylate (HEMA) with (2-{[2-(ethoxycarbonyl)prop-2-en-1-yl]oxy}ethyl) phosphonic acid (ECPPA) as important adhesive monomer used in dentistry yields reactivity ratios of r_HEMA = 1.83; r_ECPPA = 0.42. The copolymerization diagram reflects nonideal, non-azeotropic copolymerization. The sequence distribution of the obtained by Monte Carlo simulation indicates the generation of statistical copolymers. As an important finding, it is demonstrated that the repeating units responsible for etching and adhesion are arranged over the whole polymer chain, which is necessary to achieve proper functionality. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48256.     

Process design and techno‐economic analysis of ethyl levulinate production from carbon dioxide and 1,4‐butanediol as an alternative biofuel and fuel additive

Carbon dioxide capture, utilization, and storage (CCUS) is one of the promising negative emission technologies (NET). Within various CCUS routes available, CO₂ conversion into fuels is one of the attractive options. Currently, most of CO₂ conversion into fuels requires hydrogen, which is expensive and consume large energy to produce. Hence, a different route of producing fuel from CO₂ by utilizing 1,4‐butanediol as the raw material is proposed and evaluated in this study. This alternative route comprises production of levulinic acid from the reaction between CO₂ and 1,4‐butanediol and production of ethyl levulinate, an alternative biofuel and biofuel additive, via an esterification reaction of levulinic acid with ethanol. The process is designed and simulated according to the available data and evaluated in terms of its technical features. Because of the unavailability of reaction data for synthesis of levulinic acid from 1,4‐butanediol and CO₂, several assumptions were taken, which may implicate the accuracy of the studied design. This technical evaluation is followed by cost estimations and sensitivity analysis. Because of the free CO₂, the profitability of the plant depends strongly on the prices of the other chemicals and the price difference between 1,4‐butanediol (raw material) and ethyl levulinate (product). Monte Carlo simulation indicates that the proposed plant will always be profitable if the ethyl levulinate is slightly more expensive than the 1,4‐butanediol, highlighting that the process of producing ethyl levulinate from CO₂ is economically profitable. Future research should be directed towards a catalytic system that can effectively convert CO₂ into levulinic acid, by‐products produced from the two reaction steps, and reduce the excess ethanol used in the second reaction.