کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
152741 | 456506 | 2008 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: The benzylation of xylenes using heterogeneous catalysts from rice husk ash silica modified with gallium, indium and iron The benzylation of xylenes using heterogeneous catalysts from rice husk ash silica modified with gallium, indium and iron](/preview/png/152741.png)
Rice husk ash (RHA) was used to synthesize RHA-Ga, RHA-In and RHA-Fe catalysts by direct incorporation of the respective ions into rice husk ash silica at room temperature. The prepared catalysts were used to catalyze the benzylation of p-xylene (p-Xyl) with benzyl chloride (BC). The catalysts had a BET specific surface area of ca. 272–347 m2 g−1. The catalytic activity increased with a decrease in the p-Xyl/BC molar ratio. However, the selectivity towards the mono-benzylated product decreased. RHA-Fe showed the highest catalytic activity whereas RHA-In and RHA-Ga gave higher selectivity to 2,5-dimethyldiphenylmethane (2,5-DMDPM). The catalytic activity followed the order: RHA-Fe > RHA-In > RHA-Ga. The activity of RHA catalyst towards Xyl isomers was found to follow the order: o-Xyl > m-Xyl > p-Xyl whereas the selectivity for DMDPM products decreased in the order: m-Xyl > p-Xyl > o-Xyl.
Journal: Chemical Engineering Journal - Volume 145, Issue 2, 15 December 2008, Pages 328–334