Hydrothermally bonded light inorganic material

摘要

A light inorganic material consists of a material which is filled into moulds and, hydrothermally bonded with steam at 120-300 deg C. The material comprises a mixture of finely ground light aggregate and a roughly equivalent weight of finely ground alkaline earth metal hydroxide or a dry pourable powder having surface-adhering alkaline earth metal silicate hydrates and/or gels obtained by contact of the silicate-containing light aggregate (vermiculite, pumice, perlite and/or foamed glass) with aqueous alkaline earth metal hydroxide. Excess liquid is removed and the material is then dried. The novelty is that mixtures with kieselguhr, 'Molererde' and/or zeolites are used. Also claimed is a process for producing a light inorganic material from silicate-containing aggregates and inorganic binders, in which: (a) the finely ground aggregate is either mixed with a similar weight of finely ground alkaline earth metal hydroxide or contacted with aqueous alkaline earth metal hydroxide to form surf ace-adhering alkaline earth metal silicate hydrates and/or gels, followed by separation from excess liquid and drying; (b) the dry mixture or the dried powder is filled into moulds; and (c) the mixture or powder is bonded by steam treating at 120-300 deg C for at least 30 mins.