万吨级氯甲烷生产装置技术改造

通过对气－液相甲醇氯氢化法生产氯甲烷的反应动力学及冷模试验的研究分析,确定氯甲烷合成的工艺参数,同时采用了先进的产品精制及冷凝技术,使氯甲烷生产水平产生了质的飞跃。     

亚磷酸二甲酯尾气的分离回收工艺

介绍了亚磷酸二甲酯生产中尾气回收的工艺原理,对尾气中氯化氢及氯甲烷的分离回收过程进行了分析;提出了采用吸收剂分段循环和降温相结合的回收工艺,将此工艺应用于3万t/a的亚磷酸二甲酯生产装置的尾气回收上,可使氯化氢的回收率达99.9%,氯甲烷的回收率达93%以上,盐酸质量分数大于30%,尾气中氯甲烷的质量分数小于5%。     

氯甲烷收率低的原因探析

分析了氯甲烷生产中收率低的原因,并对如何提高氯甲烷收率提出了一些对策。     

甲醇液氯法联产氯代甲烷的工艺特点及其发展前景

介绍了以甲醇、液氯为原料的两步反应法生产氯代甲烷,即甲醇气相催化生产一氯甲烷和一氯甲烷液相催化生产其他氯代甲烷的工艺特点及其发展前景。     

氯甲烷收率低的原因探析

介绍了氯甲烷生产中收率低的原因，并对如何提高氯甲烷收率提出了一些对策。     

Stauffer化学公司甲烷氯化物技术

本文简述了甲烷氯化物行业发展动态，通过介绍Ｓｔａｕｆｆｅｒ化学公司甲烷氯化物技术基本情况，提供其氯甲烷生产技术参数，希对同行业技改及项目引进有所参考。     

二苯氯甲烷衍生物在原料药合成中的研究进展

二苯氯甲烷及其衍生物作为一类医药中间体,具有较好的应用前景.综述了4-氯二苯氯甲烷、4-氯二苯溴甲烷、4,4'-二氟二苯甲基氯甲烷的合成工艺,并介绍了它们在原料药美克洛嗪、西替利嗪以及氟苯桂嗪合成中的研究进展.     

氯甲烷工艺改造及其副产物的利用

我国氯甲烷生产有较大的发展,特别是利用易得的甲醇和氯化氢气体来生产氯甲烷的发展更为突出。这给我国氯碱企业解决部分氯化氢气体出路问题无疑起到了积极地推动作用。     

氯甲烷制备工艺中的节能环保措施

鉴于氯甲烷合成环节对有机硅甲基单体生产的重要意义,同时为响应国家节能减排号召,归纳了近年来氯甲烷制备工艺的节能、环保措施,以期推动有机硅行业的可持续发展.     

亚磷酸二甲酯尾气中氯甲烷回收的工艺实践

本文介绍了从亚磷酸二甲酯生产尾气中回收氯甲烷的工艺，采用降温干燥，固碱干燥和压缩相结合的方法，可使回收氯甲烷的浓度达９９％以上。     

Co-reaction of Ethene and Methylation Agents over SAPO-34 and ZSM-22

Co-reaction of ethene and different methylation agents (i.e. methanol and chloromethane) was carried out over SAPO-34 and ZSM-22 and the results are compared. It was found that the enhancement of ethene conversion was achieved by co-feeding it with methylation agents. In the ethene–chloromethane system, the methylation of ethene by chloromethane was more prominent compared with that of the co-reaction of ethene and methanol. The reasons for the differences between ethene–methanol and ethene–chloromethane co-reaction system are discussed. Complete suppress of direct conversion of methanol or ethene could be achieved over ZSM-22 by pre-coking, and propene selectivity higher than 80% was obtained at lower conversions.     

乙基麦芽酚合成中水解工艺的改进

为了提高乙基麦芽酚的产率和减少废水中氯化钠的含量,采用密闭水解法对以糠醛和氯气为原料合成乙基麦芽酚过程中的常压水解步骤进行改进。通过正交实验对密闭水解法的工艺条件进行了优化,并确定了适宜的工艺条件为:反应温度125℃,反应压力2.1 MPa,溶剂中甲醇的体积分数65%,反应时间3.5 h。与常压水解法比较,乙基麦芽酚的产率可以提高3.9%,氢氧化钠消耗量降低78%,废水中氯化钠的含量降低77.4%,副产品氯甲烷可以回收利用。     

氯甲烷生产技术进展

简要介绍了甲醇氢氯化法制备氯甲烷的 3种技术路线 :气 -液相非催化法、气 -液相催化法和气 -固相催化法。分析了国内氯甲烷的生产状况并认为气 -液相催化法和气 -固相催化法是开发的重点     

Ionic Liquids for Chloromethane/Isobutane Distillative Separation: Express Screening

The present study centres on room‐temperature ionic liquids (ILs) as entrainers in extractive distillation of chloromethane/isobutane mixtures. The binary system, chloromethane/isobutene, is an azeotropic system. In this study, IL entrainers are shown to be able to break the azeotrope and, thus, assure the separation in the whole range of chloromethane/isobutane ratios. ILs formed from different cations and anions are considered and their influence on chloromethane/isobutane separation is explored. Among the ILs studied, those containing the trifluoromethanesulfonate ([CF₃SO₃]^–) or tricyanomethanide ([C(CN)₃]^–) anion are demonstrated to exhibit an enhanced potential for chloromethane/isobutane separation compared to the corresponding ILs based on the bis(trifluoromethylsulfonyl)imide ([Tf₂N]^–) anion. Moreover, the ILs enclosing these anions are cheaper than those with the [Tf₂N]^– anion. Thus, the separation ability, solubility of chloromethane/isobutane mixtures, and costs of IL entrainers can be adjusted by the right choice of cations and anions.     

SAPO分子筛上氯甲烷催化转化制氯乙烯单体

采用水热合成法制备了SAPO分子筛,考察磷与铝物质的量比对SAPO分子筛催化转化氯甲烷制氯乙烯单体反应催化性能的影响.结果表明,SAPO-34在氯甲烷催化转化制备氯乙烯单体反应中,表现出较好的催化性能及稳定性.     

氯化氢、氯甲烷在偏三甲苯中的溶解度

建立了一套测定气体在液体中溶解度的实验装置.分别测得温度在293—323K、压力在6—130kPa范围内氯化氢、氯甲烷在偏三甲苯中的溶解度.在原装置的基础上,配以气相色谱分析,对氯化氢和氯甲烷混合气体在偏三甲苯中的溶解特性作了初步研究.实验数据用修正的Henry公式处理,其中(不对称归一化)活度系数由二尾标Margules方程关联.另外,还测定了298K、常压下H_2、N_2、CO、Ar、CH_4、CH_3Cl、HCl在偏三甲苯中的溶解度.除量子气体H_2外,其它气体的实测值与Scatchard-Hildebrand理论估算值较为接近.     

An infrared spectroscopic study of the mechanism of chloromethane conversion to higher hydrocarbons on HZSM5 catalyst

Investigation of the reaction mechanism of chloromethane on ZSM5 is a new topic. In this work an in situ FTIR technique was employed to study the conversion processes of chloromethane, the active sites on HZSM5, and the desorption state of surface species. The catalytic conversion of chloromethane to higher hydrocarbons was also studied. It is demonstrated that chloromethane can be reversibly adsorbed on acidic sites of HZSM5 at room temperature. At 100°C chloromethane is irreversibly and dissociatively adsorbed on the strong acidic sites of HZSM5, on which surface methoxyl is formed as proved by infrared characteristic C-H stretchings of-CH₃ at 2960 and 2870 cm^–1. Alkoxyls are produced and adsorbed on the catalyst surface as characterized by the infrared absorption bands of -CH₂-groups at 1460 and 2930 cm^–1. At 100°C the adsorbed methoxyl and alkoxyls are the main surface species, and a small amount of aromatics might exist as detected by a characteristic absorption band at 1510 cm^–1. Between 100 and 200°C the adsorbed surface methoxyl and alkoxyls are converted to aromatics, and the occupied OH groups partially appear. At temperature higher than 300°C the adsorbed aromatics are thermally desorbed into the gas phase. Aromatics and alkanes are the main products in catalytic conversion. These results reveal that the formation of aromatics from methoxyl and alkoxyls is easier than the desorption of aromatics from HZSM5 catalyst. An alkoxyl mechanism is proposed for the conversion of chloromethane on HZSM5 based upon the experimental results and the three assumptions: (a) The primary C-C bond is formed from surface methoxyl groups via the methoxyl group polarization and C-H bond weakening, (b) The adsorbed alkoxyls are converted to aromatics via hydrogen transfer and bond rearrangement similar to the conventional carbenium ion mechanism for the aromatization of olefins and alkanes on HZSM5. The hydrogen atoms from the aromatization stimulate the desorption of alkoxyls to alkanes. (c) At temperature higher than 300°C surface reactions and desorption of adsorbed species take place simultaneously, determining the product distribution in the catalytic conversion.     

Lab-Scale Microreactor Plant for the Study of Methylations with Liquid Chloromethane

Chloromethane is an important reagent for methylations in the process industry. However, as a gas suspected of causing cancer, it is rarely used at laboratory scale. Therefore, a setup is presented here for studies in a laboratory under safe and reproducible conditions. The use of a microreactor guarantees high heat transfer rates and a low holdup of the reagent. As a proof-of-concept, the reaction of chloromethane with the secondary amine morpholine in aqueous solution is investigated. By applying elevated pressures, a liquid-liquid system with enhanced solubility of chloromethane in the aqueous phase is accessible.     

邻苯二甲醚的合成改进

介绍了以氯甲烷和邻苯二酚为原料合成邻苯二甲醚的方法。通过物料配比、反应压力和催化剂等几个方面的条件优化,产品含量和收率得到了很大的提高。     

单体合成中影响甲基氯硅烷产品质量的因素分析

分析了甲基氯硅烷合成反应中硅粉、氯甲烷、催化剂及助剂、温度、压力等因素对二甲基二氯硅烷质量的影响,给出了提高二甲基二氯硅烷产品质量一些建议。