GB419387A - Improvements in or relating to fertilizers - Google Patents

Abstract

In the production of fertilizers an aluminium salt, e.g aluminium nitrate and a soluble silicate are caused to react with one another to produce a fertilizing salt and aluminium hydrosilicate or a mixture of aluminium hydrate and colloidal silicic acid in such a form as to be easily decomposable and assimilable by the root fibres. The soluble silicate may be water-glass preferably potash water-glass. Fertilizing substances, e.g. superphosphate, sodium nitrate, ammonium phosphate or substances containing potassium may be added to the finished product. The process may be carried out in the presence of ions of phosphoric acid so that aluminium phosphate is formed in addition to the aluminium silicate. The soluble silicate may be replaced by colloidal silicic acid and the fertilizing salt is provided by the addition of potassium or ammonium phosphate which reacts with the aluminium salt. These processes may be carried out in the presence of a material having a large surface, e.g. brown coal, peat, clay, kaolin. To the products of the processes may be added compounds of elements having a stimulating effect on the growth of plants, e.g. germanium, gallium, hafnium, titanium, manganese, in the same or in somewhat greater proportions than those in which they are present in the naturally occurring aluminium silicates. The Specification as open to inspection under Sect. 91 also states that fertilizers may comprise wholly or partly mixtures of colloidal silicic acid and active aluminium oxide. This subject-matter does not appear in the Specification as accepted.