CoMo/TiO2-Al2O3催化剂的气相氟化改性

采用连续流动微型催化反应装置和氮气吸附等方法研究了气相预氟化和氟化铵溶液浸渍处理对CoMo/ TiO2-Al2O3噻吩加氢脱硫催化活性和物化性能的影响.通过对0.5 ％～7 ％ (φ)各种氟里昂浓度和473～773 K各种温度及不同时间氟化处理的样品进行详细考察,发现在623 K下由含氟里昂1％(φ)的湿空气氟化的载体制备的催化剂样品,其噻吩的加氢脱硫的活性有明显改善,相对于非氟化样品、BY-2工业催化剂以及氟化铵溶液浸渍处理的催化剂活性提高20％～30％,且非常稳定.初步表征还表明,氟里昂气相加氟与氟盐溶液浸渍加氟相比较,有不破坏催化剂结构和不降低催化剂比表面积的优点.

Modification of CoMo/TiO2-Al2O3 Catalyst by Gas Phase Fluorination

The effect of support pre-fluorination on the physical properties and catalytic activity of MoCo/TiO2-Al2O3 was studied by XRD, N2 adsorption ,and thiophene hydrodesulfurization (HDS).Freon (CFC-12) in wet air or in NH4F solution was used as fluorinating reagents. The influences of CFC-12 content, effect of fluorination temperature and fluorinating time on the structure and hydrodesulfurization activity of the catalysts were examined systematically. The results revealed that hydrodesulfurization activity of the catalyst fluorinated by 1％ CFC-12 at 623 K was obviously improved with an increase of 20％～30 ％ as compared with that of the unfluorinated catalyst, the commercially available BY2 catalyst, and NH4F-fluorinated catalysts. Moreover, the catalyst fluorinated by the Freon gas presented excellent stability on catalytic activity and structure.