Separation Process with Cuprous Halide Sorbents

1,152,548. Recovering organic compounds via cuprous halide complexes. ESSO RESEARCH & ENG. CO. 1 Dec., 1967 [10 Jan., 1967], No. 54885/67. Heading C2C. [Also in Division C5] A process for selectively recovering complexable ligands comprises contacting a feed containing said ligands with a cuprous halide sorbent in the presence of a contaminantrejecting material selected from (a) compounds of the formula where R111 is a C 1 -C 12 alkyl group and n is an integer from 2 to 12, (b) compounds of the formula where R and R1 are H or C 1 -C 18 alkyl groups and R11 is a C 1 -C 18 alkyl group and (c) mixtures of (a) and (b); and desorbing said complex to recover the ligand in higher purity. The process may be carried out in the liquid phase using a slurry of cuprous halide in an organic liquid diluent having a boiling point higher than the complexable ligand and composed of materials less preferentially complexable with cuprous halide than the ligand or in the vapour phase. Many organic ligands are listed, but an example is given of the recovery of acrylonitrile from a mixture of acrylonitrile and acetonitrile using a CuCl slurry in toluene containing 5% of N,N-dimethyloleamide.