Melamine prodn. by conversion of urea at elevated temp. - in an appts. of austenitic alloy steel contg. chromium, nickel, carbon, and niobium to avoid corrosion

摘要

Melamine is produced by conversion of urea and/or thermal decompsn. prods. of this at a temp. of 300-450 deg.C, using an appts. in which at least part of the surface in contact with the reaction mixt. is made of an alloy with an austenitic structure and consisting of 16-19wt.% Cr, 8-14wt.% Ni, 0-1.0wt.% Si, 0.03-0.12wt.% C and a content of Nb of between eight times the carbon content and 1.2wt.%, and a remainder of Fe and minor impurities.