| abstract |
Disclosed is a modified free acid type heteropolyacid that can be easily immobilized on a carrier. A free acid type heteropolyacid represented by the general formula (1). H m [X (YOH) a O b ] ยท nH 2 O (1) [Wherein, X is a heteropolyanion in which a part of the skeleton constituent atoms is missing, Y is any one atom selected from Si, Ti, Al and Zr, and m is an integer of 1 or more. The absolute value of the negative charge determined from [X (YOH) a O b ] in the general formula (1), and n is an integer of 1 or more. A is 1 or 2, b is 0 when a is 1, and 1 when a is 2. ] [Selection figure] None |