一种新型医药中间体的合成研究

N-苄基-N-甲基乙醇胺是一种合成医药、染料、农药等的中间体。文章通过对N-苄基-N-甲基乙醇胺的工业生产流程的介绍,以N-甲基苄胺和环氧乙烷为原料,探索最佳反应控制条件,合成出具有高收率和高选择性的N-苄基-N-甲基乙醇胺。     

医药中间体N,N-二乙基乙醇胺的合成

常压下用二乙胺溶液中通环氧乙烷的方法来合成N，N-二乙基乙醇胺，回收过量二乙胺后，蒸馏得到98％以上的产品，该路线工艺简单，收率高。     

由乙醇胺制备N,N—二甲基乙二胺

该文以乙醇胺为原料经酸化、氯化、氮甲基化合成Ｎ、Ｎ－二甲基乙二胺,收率７７．３％。     

N,N—二苄基苯胺的制备

本文主要叙述了Ｎ，Ｎ－二苄基苯胺的产品特点，技术规格及工艺操作方法。     

N—甲基—N—羟乙基苯胺制备

以Ｎ－甲基苯胺和环氧乙烷为原料，采用气相非均相法合成了Ｎ－甲基－Ｎ－羟乙基苯胺。在反应温度１２０－１４０℃，反应压力０．４－０．６ＭＰａ，催化剂 ０．３％－０．４％的条件下，得到了较好的产品质量和收率。     

N—甲基二乙醇胺脱硫剂发展动向

介绍了N-甲基二乙醇胺脱硫剂在脱除酸性气体方面的性质及其在国内外的发展动态。     

N-乙基-N-苄基间磺酸苯胺中异构体的分离研究

对N-乙基-N-苄基间磺酸苯胺中间位、对位及邻位异构体进行了分离研究，用苯甲醛邻磺酸与N-乙基-N-苄基闯磺酸苯胺混合物缩合，制成衍生物，再用HPLC(色谱柱：CLC-ODS，检测波长：254nm，流动相：甲醇／四丁基溴化铵=60％／40％)分离，可使异构体得到有效分离，并能判断N-乙基-N-苄基间磺酸苯胺商品中间位物主含量的高低。     

中空纤维膜接触器中N,N-二甲基乙醇胺吸收CO2的特性

N,N-二甲基乙醇胺（DMEA）是一种很有前途的吸收剂,具有较快的反应速率和较高的CO₂捕集能力。在本研究中,DMEA作为一种新型吸收剂被应用于中空纤维膜接触器,用于从CO₂/CH₄气体混合物中分离CO₂。通过建立二维稳态数学模型,模拟了MEA、DEA、MDEA和DMEA四种吸收剂在不同操作条件下对CO₂吸收性能的影响。结果表明,脱碳性能大小为MEA>DMEA>DEA>MDEA;气相参数对脱碳率的影响比液相参数更显著;提高气体流速和CO₂浓度,脱碳率均会下降;提高液速和吸收剂浓度,脱碳率均增大,适当提高吸收剂流速和吸收剂浓度可以提高CO₂去除效率。此外,CO₂吸收通量将随着气体速度的增加而增加,随着液相中CO₂负荷的增加而减少。最后,通过两种影响因素共同作用确定了膜接触器分离酸性气体的最佳操作条件。因此,膜吸收法在天然气脱碳方面有良好的潜力。     

大力开发绿色节能清洁酒精工业与乙醇汽油、乙醇柴油

介绍了发展绿色节能酒精工业前景 ,并提出了发酵酒精原料综合利用、节能生产工艺和推广应用乙醇汽油、乙醇柴油的建议。     

车用乙醇汽油中变性燃料乙醇的检测方法

本文介绍了目前检测乙醇汽油中变性燃料乙醇的方法,比如常压蒸馏曲线判断法、气相色谱法、红外光谱检测法及核磁共振波谱测定法等,对车用乙醇汽油推广应用过程中存在的问题进行了评述,讨论了其未来的发展。     

Ethanol dehydration by extractive distillation

Experiments and process simulation enable favourable operating conditions to be determined for the extractive distillation of ethanol—water, with ethylene glycol as a solvent. The solvent molar rate to feed molar rate ratio S/F = 0·6 and the reflux ratio R = 0·5 were determined in order to achieve at least 99·5 mole % purity of ethanol. Other parameters examined include feed concentration, purity of solvent, and number of plates. Extractive distillation can be used to achieve high purity of ethanol at low energy consumption and under simple operating conditions.     

同步闪蒸汽提发酵制乙醇

为提高乙醇生产发酵强度,提出了同步汽提闪蒸乙醇发酵新过程。该过程集合了闪蒸发酵和汽提发酵的优点,在发酵的同时能更有效地在位分离乙醇,从而提高发酵强度。通过与普通发酵、闪蒸发酵、汽提发酵等过程进行间歇实验比较,同步闪蒸汽提发酵过程具有发酵强度高的优势;而且,采用耐高温酵母高温发酵、提高通气量、闪蒸罐的进料流速可进一步提高其发酵强度。该过程简单、高效,具有工业应用的潜力。     

Photoaddition of Acetylcyclohexane and Ethanol

1-Acetylcyclohexene undergoes photoaddition with ethanol to give, initially, cis- and trans-2-ethoxy-1-acetylcyclohexane. The thermodynamically less stable cis isomer is the major product. No products resulting from photochemical hydrogen atom abstraction from ethanol by photoexcited ketone were observed in contrast to the results obtained with an acetylcyclopentene derivative. The initially formed adducts undergo a further photochemical reaction, intramolecular hydrogen atom abstraction, to give derivatives of octahydrobenzofuran. Quantum yields for disappearance of acetylcyclohexene in ethanol were 0.04 at 2537Å and 0.25 at 3130Å.     

Heat Integrated Ethanol Dehydration Flowsheets

Abstract

A theoretical evaluation of heat-integrated heterogeneous-azeotropic ethanol-water distillation flowsheets is presented. Simulations of two column flowsheets using several different hydrocarbon entrainers reveal a region of potential heat integration and substantial reduction in operating energy. In this paper, methods for comparing hydrocarbon entrainers are shown.

Two aspects of entrainers are related to operating and capital costs. The binary azeotropic composition of the entrainer-ethanol mixture is related to the energy requirements of the flowsheet. A temperature difference in the azeotropic column is related to the size of the column and overall process staging requirements. Although the hydrophobicity of an entrainer is essential for specification of staging in the dehydration column, no substantial increase in operating energy results from an entrainer that has a higher water content. Likewise, liquid-liquid equilibria between several entrainer-ethanol-water mixtures have no substantial effect on either staging or operation. Rather, increasing the alcohol content of the entrainer-ethanol azeotrope limits its recovery in the dehydration column, and increases the recycle and reflux streams. These effects both contribute to increasing the separation energy requirements and reducing the region of potential heat integration.

A cost comparison with a multieffect extractive distillation flowsheet reveals that the costs are comparable; however, the extractive distillation flowsheet is more cost effective as operating costs increase.

The destruction of organic model substances by indirect electrooxidation was investigated. The oxidation agent Co(III) was used because of the high redox potential of the Co(III)/Co(II) redox couple (E₀ = 1.808 V).

Several supercritical fluid extraction (SCFE) processes have been proposed for removing toxic and intractable organic compounds from a range of contaminated solids. These include soil remediation and the regeneration of adsorbents used to treat wastewater streams such as granular activated carbon (GAC). As a separation technique for environmental control, SCFE has several distinct advantages over conventional liquid extraction methods and incineration. Most notably, the contaminant is removed from the solvent in a concentrated form via a change in pressure or temperature and can be completely separated upon expansion to atmospheric pressure.

The viability of SCFE hinges on process conditions such as solvent-feed ratio and solvent recycle ratio. The necessity of recycling solvent complicates the contaminant separation step since a complete reduction to atmospheric pressure would create large recompression costs. Because of this, the pressure and temperature dependence of contaminant solubility must be understood so that operating conditions for the separation step can be defined. Fortunately, this is the most developed aspect of SCF technology. However, the mass transfer limitations to removing contaminants from solids change with solvent flow rate.

This paper discusses the use of SCFE for environmental control and presents results for the removal of DDT and 2-chlorophenol from GAC. 2-chlorophenol is almost completely removed with pure CO₂ at 40°C and 101 bar while only 55% of the DDT is removed at 40°C and 200 bar. These differences in regeneration efficiency cannot be understood solely in terms of solubility but point to a need for detailed studies of adsorption equilibrium and mass transfer resistances in supercritical fluid systems.