中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
丙酸甲酯和甲醛合成甲基丙烯酸甲酯Cs-P基催化剂研究

文献类型:学位论文

作者郭志军
答辩日期2020-07-01
授予单位中国科学院大学
导师李春山
关键词丙酸甲酯,甲醛,羟醛缩合反应,Mma
学位名称硕士
学位专业化学工程
英文摘要

甲基丙烯酸甲酯(MMA)是一种重要的化工原料,主要用于生产有机玻璃等高附加值化学品;由于其优异的性能和广泛的用途,全球MMA的需求量近10年来以近10%的速度增加。传统的MMA合成工艺主要为丙酮氰醇法,该工艺原料氢氰酸剧毒,且产生大量的废水、废固,环保压力越来越大。因此,开发新型的MMA合成技术具有重要的意义。本论文研发了丙酸甲酯和甲醛合成MMA的新过程,获得了酸碱催化剂。主要创新性如下:(1)以Cs、P为活性组分,通过等体积浸渍法制备了不同载体(γ-Al2O3、SiO2、TiO2、ZrO2、CeO2)的负载型催化剂,并用固定床反应装置评价了不同载体Cs-P/Y催化剂的活性,获得了活性较优、稳定性较好的Cs-P/γ-Al2O3催化剂。通过不同的表征技术揭示了Cs-P/γ-Al2O3催化剂活性较好的原因,其中酸碱性、比表面积是影响催化剂活性的关键因素。(2)通过Fe对Cs-P/γ-Al2O3催化剂进行改性,并利用TPD、Pyridine-FTIR、XPS等表征系统研究了助剂Fe的影响规律。适量Fe的引入可以提高催化剂表面酸活性中心的数量,催化剂表面的酸中心为中等强度的Lewis酸;Fe可以调控催化剂表面磷物种的分布,从而影响Lewis酸量和酸强度。(3)对反应条件进行了优化,最优反应温度为370°C,液时空速为1.2h-1, 此时丙酸甲酯转化率为29.06%,MMA选择性为90.67%。对催化剂的稳定性进行了考察,积碳是催化剂活性降低的主要原因,经过三次再生循环(260h)后,再生催化剂的活性没有降低。另外,对催化剂进行了放大制备并对其活性进行评价。;Methyl methacrylate (MMA) is an essentially important monomer, used to produce organic glasses and other high-value chemicals. The demand for MMA increases rapidly due to its special properties and broad applications. At present, the traditional route for producing MMA is Acetone cyanohydrine (ACH). This route uses large amounts of toxic hydrocyanic acid and produces large amounts of wast water and solid wast. The pressure from environmental protection is increased. Thus, developing the new MMA production process is of great importance. In this work, the new process for synthesizing MMA from methyl propionate and formaldehyde was developed. The acid-base catalysts were obtained. The main research work and innovations are as follows:(1)A series of catalysts with different supports (γ-Al2O3, SiO2, TiO2, ZrO2, CeO2) were developed using impregnation method with Cs, P as active components. The performances of Cs-P/Y catalysts were evaluated through the fixed bed reactor. The best support was obtained and different characterizations were used to reveal the intrinsic reason of better activity. The surface area and acid-base property are the key element to promote catalytic activity.(2)The metal Fe was used to modify Cs-P/γ-Al2O3 catalyst and physico-chemical properties of Cs-P-Fe/γ-Al2O3 catalysts with different Fe contents were investigated systemically through TPD, Pyridine-FTIR and XPS. Adding promoter Fe can increase the amount of medium acid sites. The acid sites on surface of catalysts were medium Lewis acid. Importantly, promoter Fe can adjust the proportion of phosphorus species effectively, which has a huge influence on the amount and strength of Lewis acid.(3)The reaction conditions such as temperature and LHSV were optimized. The best catalytic performance was obtained at 370 °C, LHSV=1.2 h-1. Conversion of MP was 29.06% and MMA selectivity reached 90.67%.The stability of the optimized catalyst was studied. The deposition of cokes is the main reason for deactivation. After three reproduced circles, the regenerated catalyst presents the same catalytic performance as the initial catalyst. In addition, the optimized catalyst was prepared in large scale and evaluated in a large-scale fixed bed reactor. 

语种中文
源URL[http://ir.ipe.ac.cn/handle/122111/49638]  
专题中国科学院过程工程研究所
推荐引用方式
GB/T 7714
郭志军. 丙酸甲酯和甲醛合成甲基丙烯酸甲酯Cs-P基催化剂研究[D]. 中国科学院大学. 2020.

入库方式: OAI收割

来源:过程工程研究所

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