| abstract |
The present invention is a composite metal oxide catalyst represented by the following formula (1) and a method for producing the same, and activating the catalyst, the reaction temperature is 130 ~ 220 ℃, hydrogen molar ratio to phthalate ester is 500 ~ 3,000, the reaction pressure is atmospheric pressure ~ 10 atm Phthalate ester direct gas phase catalytic reaction under the conditions of the present invention relates to a process for preparing phthalide:n n n n n [CuO (a) ZnO (b) MnO 2 (c) SiO 2 (d)] (100-x) M (x)n n n n n Wheren n n M is an oxide of at least one metal element selected from oxides of rhenium (Re), ruthenium (Ru), and silver (Ag),n n n A, b, c, d, x in parentheses are expressed by weight, a is 20 to 90, b is 0.01 to 10, c is 0.01 to 5, d is 5 to 65, and x is 0 To 5 in the range.n n n In the process of the present invention, in the preparation of phthalide from phthalate ester, it has the effect of long-term stable production of phthalide at high selectivity under mild reaction conditions. |