Structure and reactivity of phosphorous modified H-ZSM-5 catalysts for ethanol dehydration

H(3)PO(4)/H-ZSM-5 catalysts were prepared by impregnation method with varying H(3)PO(4) loadings from 5 to 20 wt%. The H(3)PO(4) modified catalysts were found to be highly active and selective towards ethylene during ethanol dehydration at 673 K. However, the selectivity was found to strongly depend on the content of H3PO4, reaction temperature and WHSV. The catalysts were characterized using X-ray diffraction, NH(3)-TPD, N(2) physisorption, (27)Al, and (31)P MAS NMR techniques. (C) 2008 Elsevier B.V. All rights reserved.