Vapor phase process for production of acrylonitrile

Claim 1

IN A METHOD FOR THE PREPARATION OF ACRYLONITRILE BY REACTING AOETYLENE WITH HYDROGEN CYANIDE IN THE VAPOR PHASE IN THE PRESENCE OF A SOLID CATALYST AT TEMPERATURES OF ABOUT 450* TO 700*, THE STEPS WHICH COMPRISE PASSING A REACTION GAS CONTAINING ACETYLENE AND HYDROGEN CYANIDE UPWARDLY THROUGH THE CATALYST IN A REACTION ZONE, SAID CATALYST BEING CONTINUOUSLY PASSED DOWNWARDLY THROUGH THE REACTION ZONE COUNTERCURRENT TO THE REACTION GAS, THE CATALYST BEING INTRODUCED INTO THE UPPER END OF THE REACTION ZONE AS FRESH CATALYST AND BEING WITHDRAWN FROM THE LOWER END AS SPENT CATALYST AND THE VELOCITY OF THE REACTION GAS BEING BELOW THE DANCING POINT OF THE CATALYST AND BEING BETWEEN 200 TO 1500 TIMES THE VELOCITY OF THE CATALYST WHICH IS PASSED COUNTERCURRENTLY THERETO THROUGH THE REACTION ZONE.