A SOLUTION OF COPPER(I) CHLORIDE PYRIDINE COMPLEX IN ACETONITRILE AS ABSORBENT FOR CARBON-MONOXIDE

A solution of copper( I) chloride-pyridine complex in acetonitrile was prepared by addition of pyridine to an acetonitrile suspension of cop per(I) chloride under nitrogen. The solution of copper(I) chloride-pyr idine complex in acetonitrile, 10 cm(3), prepared from 10.0 mmol of co pper(I) chloride, 40.0 mmol of pyridine, and acetonitrile rapidly abso rbed carbon monoxide at 30 degrees C under 1.0 atm of carbon monoxide. The equilibrium amount of absorbed carbon monoxide was 5.90 mmol (59% against admitted copper( I) chloride). The absorbed carbon monoxide w as rapidly released to gas phase by maintaining the solution at 70 deg rees C under 1.0 atm. The amount of released carbon monoxide in equili brium was 5.21 mmol (88% against absorbed carbon monoxide). The absorp tion-release cycle was repeated without any deterioration. The reversi ble absorption of carbon monoxide under mild conditions was attributed to formation of 1 : 1 : 1 copper( I) chloride-pyridine-carbon monoxid e complex from carbon monoxide molecule and 1 : 1 copper(I) chloride-p yridine complex in acetonitrile solution.