GB647316A - Method of production of ammonium salts of the sulphamic acids - Google Patents

Abstract

Ammonium salts of sulphamic acids (ammonium amido sulphonate, NH2SO3NH4, normal ammonium imido sulphonate, NH(SO3NH4)2, basic ammonium imido sulphonate, NH4.N (SO3NH4)2 and ammonium nitrilosulphonate, N(SO3NH4)3) are made by mixing with anhydrous ammonia the hot SO3-containing gases obtained from the contact bodies in the contact-process for making sulphuric acid, and recovering the sulphamic acid salts from the reaction mixture. Gaseous or liquid ammonia, e.g. in finely-divided form, may be used and may be diluted with air or other inert gas. The composition of the reaction product is mainly dependent on the ratio NH3 : SO3, the reaction temperature which may be below the melting point of the reaction product, and on the duration of the reaction. The mixture of the ammonium salts may be worked up to pure products, e.g. by recrystallization. Ammonium amidosulphonate on heating forms the normal imido sulphonate and ammonia, and the nitrilosulphonate hydrolyses to the imidosulphonate and acid ammonium sulphate. The prior art discloses the preparation of potassium nitrilo and imido sulphonates from potassium nitrate and potassium bisulphite, amidosulphonic acid from urea and chlorsulphonic acid, ammonium imido sulphonate from pure sulphur trioxide and ammonia in the form of gas or liquid spray and basic ammonium imidosulphonate from sulphur trioxide and aqueous ammonia.ALSO:Mixtures of ammonium salts of sulphanic acids (ammonium amido sulphonate, NH2SO3NH4, normal ammonium imido sulphonate, NH (SO3NH4)2, basic ammonium imido sulphonate, NH4N (SO3 NH4)2, and ammonium nitrilosulphonate, N(SO3NH4)3), made by mixing with anhydrous ammonia the hot SO3-containing gases issuing from a sulphuric acid contact-process (see Group III), may be used as a nitrogenous fertilizer.