Porous hydrous zirconia supported 12-tungstophosphoric acid catalysts for liquid-phase esterification of 2-ethyl-1-hexanol

12-Phosphotungstic acid Supported on porous hydrous zirconia was prepared and characterized by N(2) adsorption isotherm. powder XRD, FTIR, (31)P MAS NMR, H(2)-TPR, NH(3)-TPD, SEM and TEM. It is found that the chemical interaction of Keggin anions with hydrous zirconia is different compared to the interaction with ZrO(2) and Ce(0.5)Zr(0.5)O(2) supports. The phosphotungstic acid clusters dispersed on porous hydrous zirconia did not show any split of IR bands at 1080cm(-1) (upsilon(P-O)) and 983 cm(-1) (upsilon(W=O.ter)) while those dispersed on ZrO(2) and Ce(0.5)Zr(0.5)O(2) showed a split in these two bands clue to the lowering ofsyrnmetry of the central PO(4) tetrahedron and direct interaction of W=O(ter) with oxide Support. The dispersion Of phosphotungstic acid on porous hydrous zirconia led to the growth of crystallites which showed catalytic activity for liquid-phase esterification of 2-ethyl-1-hexanol with acetic acid. Both conversion of 2-ethyl-1-hexanol and selectivity for 2-ethyl-1-hexyl acetate can be achieved at 100%. (c) 2008 Elsevier BY. All rights reserved.