催化学报 ›› 2017, Vol. 38 ›› Issue (10): 1697-1710.DOI: 10.1016/S1872-2067(17)62891-2

• 论文 • 上一篇    下一篇

容碳的SiW20-Al/Zr10催化剂用于甘油脱水制丙烯醛

Amin Talebian-Kiakalaieh, Nor Aishah Saidina Amin   

  1. 马来西亚理工大学化学与能源工程学院化学反应工程研究组(UTM), 士古来 81310, 柔佛, 马来西亚
  • 收稿日期:2017-03-24 修回日期:2017-06-30 出版日期:2017-10-18 发布日期:2017-10-28
  • 通讯作者: Amin Talebian-Kiakalaieh, Nor Aishah Saidina Amin

Coke-tolerant SiW20-Al/Zr10 catalyst for glycerol dehydration to acrolein

Amin Talebian-Kiakalaieh, Nor Aishah Saidina Amin   

  1. Chemical Reaction Engineering Group (CREG), Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia (UTM), Skudai 81310, Johor, Malaysia
  • Received:2017-03-24 Revised:2017-06-30 Online:2017-10-18 Published:2017-10-28
  • Contact: 10.1016/S1872-2067(17)62891-2

摘要:

将一系列负载型硅钨酸催化剂用于甘油脱水制丙烯醛反应中.表征结果表明,最终所得催化剂具有高的热稳定性、大的孔径、强的L酸位和大的比表面积.X射线光电子能谱中清晰地出现归属于W(W 4f=35.8 eV),Al(Al 2p=74.9 eV)和Zr(Zr 3d=182.8 eV)元素的谱峰.在SiW20-Al/Zr10催化剂上丙烯醛选择性最高,为87.3%,此时甘油转化率为97%.由于高浓度L酸位的存在,显著降低了催化剂表面积碳量,因而该催化剂即使反应40 h之后仍具有较高地催化生成丙烯醛的活性和选择性.响应面方法表明,在以下优化条件下反应甘油转化率和丙烯醛选择性分别达87.7%和97.0%:催化剂用量0.5 wt%,进料甘油浓度10 wt%,反应温度300 ℃.传质限制评估结果显示,当颗粒尺寸dP<20 μm时,反应不存在内外扩散限制.综上可见,强L酸催化剂有望用于甘油脱水制丙烯醛反应中.

关键词: 甘油, 脱水, 丙烯醛, 多相催化, 杂多酸

Abstract:

Glycerol dehydration to acrolein over a series of supported silicotungstic acid catalysts (SiWx-Al/Zry) was investigated. Characterization results showed that the final catalyst had high thermal stability, a large pore diameter, strong Lewis acidic sites, and a large specific surface area. X-ray photoelectron survey spectra clearly showed peaks attributable to W (W 4f = 35.8 eV), Al2O3 (Al 2p = 74.9 eV), and ZrO2 (Zr 3d = 182.8 eV). The highest acrolein selectivity achieved was 87.3% at 97% glycerol conversion over the SiW20-Al/Zr10 catalyst. The prepared catalysts were highly active and selective for acrolein formation even after 40 h because of the presence of high concentrations of Lewis acidic sites, which significantly reduced the amount of coke on the catalyst surface. Response surface methodology optimization showed that 87.7% acrolein selectivity at 97.0% glycerol conversion could be obtained under the following optimal reaction conditions: 0.5 wt% catalyst, reaction temperature 300 ℃, and feed glycerol concentration 10 wt%. Evaluation of a mass-transfer-limited regime showed the absence of internal and external diffusions over pellets of diameter dP<20 μm. These results show that glycerol dehydration over a strong Lewis acid catalyst is a promising method for acrolein production.

Key words: Glycerol, Dehydration, Acrolein, Heterogeneous catalysis, Heteropoly acid