Glycerol dehydration to acrolein: Selectivity control over CsPW/Nb2O5 catalyst
Glycerol dehydration to acrolein: Selectivity control over CsPW/Nb2O5 catalyst
复制标题
甘油脱水制丙烯醛：CsPW/Nb2O5 催化剂的选择性控制
DOI：
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Tiefeng Wang
中科院分区：
文献类型：
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作者：
Chang Liu;Rong Liu;Tiefeng Wang
由于未来化石原料的枯竭和生物质甘油产量的增加，甘油催化脱水为丙烯醛是丙烯工艺的一个非常有吸引力的替代方案。本工作旨在研究Cs2.5H0.5PW12O40/Nb 2 O 5（CsPW-Nb）的选择性控制。通过FTIR对催化剂的Bronsted酸中心和刘易斯酸中心进行了表征。研究了反应温度（260 - 360 °C）、氧气共进料比（0 - 0.175）和甘油浓度（0.2 - 0.5 g/g）的影响，以确定生产丙烯醛的最佳条件。结果表明，负载CsPW的Nb_2O_5催化剂的Bronsted酸强度增加，丙烯醛脱水反应得到加强。以适当的比例共进料氧气显着提高丙烯醛脱水路线的选择性，并通过抑制甘油低聚反应略微提高丙酮醇脱水路线的选择性。当甘油浓度从0.2增加到0.5 g/g时，由于甘油低聚反应的增加，丙烯醛的选择性显著降低。甘油脱水反应中丙烯醛的选择性受反应温度、氧气共进料和甘油浓度的影响。在320 °C、O2/N2/甘油摩尔比为1/5/0.16（mol/mol）、甘油浓度为0.2g/g时获得最高的丙烯醛选择性（76.5%）。
The catalytic dehydration of glycerol to acrolein is a very attractive alternative to the propylene-based process, due to the future exhaustion of fossil feedstocks and the increasing production of biomass-based glycerol. This work aimed to study the selectivity control over Cs2.5H0.5PW12O40/Nb2O5 (CsPW-Nb). The Bronsted and Lewis acid sites were characterized by FTIR to understand the catalytic mechanism. The effects of reaction temperature (260−360 °C), oxygen co-feed ratio (0−0.175), and glycerol concentration (0.2−0.5 g/g) were studied to determine the optimum conditions for the production of acrolein. The loading of CsPW on Nb2O5 increased the Bronsted acidity and enhanced the acrolein dehydration route. Co-feeding oxygen at an appropriate ratio significantly enhanced the selectivity of the acrolein dehydration route and slightly enhanced the selectivity of the acetol dehydration route by suppressing the glycerol oligomerization reaction. The selectivity to acrolein significantly decreased when the glycerol concentration increased from 0.2 to 0.5 g/g due to increased glycerol oligomerization reactions. The acrolein selectivity in dehydration of glycerol was affected by reaction temperature, oxygen co-feeding, and glycerol concentration. The highest acrolein selectivity (76.5 %) was obtained at 320 °C, O2/N2/glycerol molar ratio of 1/5/0.16 (mol/mol), and glycerol concentration of 0.2 g/g.
影响因子：
5.5
作者：
Alhanash, Abdullah;Kozhevnikova, Elena F.;Kozhevnikov, Ivan V.
通讯作者：
Kozhevnikov, Ivan V.