Patent ID: 6960333
Filing Date: 2005-11-01
Classification: C01C,F28F

Abstract:
1. A process for preparing hydrogen cyanide comprising the steps of: feeding reaction gas to a reactor, the reaction gas comprising hydrocarbon, ammonia and optionally an oxygen-containing gas; reacting the reaction gas in the presence of a catalyst to give product gas; cooling the product gas in a heat exchange apparatus comprising (a) a shell having an entry tubesheet and an exit tubesheet, each tubesheet having a plurality of holes, wherein the shell has at least one inlet and one outlet for heat exchange medium; (b) a plurality of tubes disposed within the shell wherein an entry end of each tube is affixed to the entry tubesheet and an exit end of each tube is affixed to the exit tubesheet such that an axis of the tube and an axis of an entry and exit tubesheet hole are coincident; and (c) a plurality of ferrules, each ferrule having an entry end and an exit end extending through an entry tubesheet hole into a tube wherein the exit end extends below the entry tubesheet, the ferrule comprising silicon nitride; and recovering hydrogen cyanide from the cooled product gas.