Patent ID: 7754643

Claim:
A transesterification catalyst having the general formula: Zn 3 M 2 (CN) n (ROH). x ZnCl 2 .y H 2 O wherein R is tertiary-butyl and M is a transition metal ion selected from Fe, Co and Cr, x varies from 0 to 0.5, y varies from 3-5 and n is 10 or 12, wherein the catalyst is formed by a method comprising: a) dissolving ZnCl 2 in a mixture of water and tertiary butanol, b) adding the above said solution obtained in step (a) to an aqueous solution of K 4 M(CN) 6 , under stirring, c) adding tri-block copolymer poly(ethyleneglycol)-block-poly(propylene glycol)-block-poly(ethyleneglycol) (E0 20 -PO 70 -EO 20 ; molecular weight of about 5800) dissolved in a mixture of tert.-butanol and water to the above said resultant mixture obtained in step (b), under stirring, at a temperature in the range of 50°-70° C., d. filtering the above said reaction mixture obtained in step (c) to obtain a solid product, followed by washing with a material consisting of distilled water in an amount of at least 500 ml and drying it at 20-50° C.; and e) activating the above said dried solid product, at a temperature in the range of 150-200° C. to obtained the desired transesterification catalyst.