Patent ID: 11898007
Assignee: COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH
Field: Organic fine chemistry (Chemistry)
Classification: CPC C | IPC C

Claim 3:
4. A process for the synthesis of DMC catalyst according to claim 1 comprising the steps of:
(a) reacting an aqueous solution of metal salts of formula M(B)n and metal cyanide salt of formula (A)xM′(CN)y;
wherein M is selected from the group consisting of Zn(II), Fe(II), Pb(II), Mo(IV), Al(III), Mn(II), V(IV), V(V), W(IV), W(VI), Co(II), Sn(II), Cu(II), Cr(III), Ni(II);
B is an anion selected from the group consisting of halides, sulfates, hydroxides, cyanides, oxalates, isocyanates, thiocyanates, isothiocyanates, carboxylates, and nitrates;
n is selected from 1 to 3, which satisfies the valency of M;
A is selected from an alkali metal ion or alkaline earth metal ion;
M′ is selected from the group consisting of Fe(II), Fe(III), Co(II), Co(III), Cr(II), Cr(III), Mn(II), Mn(III), Ir(III), Ni(II), Rh(III), Ru(II), V(IV), and V(V);
Both x and y are integers greater than or equal to 1, and the sum of the charges of x and y balances the charge of M′;
in a molar ratio ranging between 1:1 to 50:1 in the presence of an organic complexing agent and co-complexing agent to obtain a reaction slurry;

(b) mixing the slurry as obtained in step (a) with polyethylene glycol (PEG) with the number average molecular weight ranging from 200 to 400 Mw and a solvent and homogenizing this mixture for a period in the range of 1 to 10 min, followed by one time centrifugation to obtain a solid cake; and
(c) adding the aqueous solutions of PEG (Mw=200 to 400), and a solvent to the solid cake obtained in step (b) at room temperature in the range of 8 to 40° C. for a period in the range of 5 to 30 min followed by precipitation, centrifugation, and vacuum drying for a period in the range of 8-12 h to attain the DMC catalyst.