Abstract: A dry one-component alkali metal silicate cement composition contains the following components:(a) condensed aluminum phosphate or condensed aluminum/iron phosphate as hardener in amounts between 2-10% by weight,(b) rounded quartz sand having a grain size between 0.01 and 0.5 mm in amounts of 30-70% by weight,(c) clay constituents in amounts of 10-40% by weight,(d) kieselguhr in amounts of 1-5% by weight,(e) mineral oil in amounts of 0.05-1% by weight and(f) solid pulverulent sodium silicate, potassium silicate or mixtures thereof in amounts of 10-25% by weight.The composition is free of surfactant. When combined with water the cement is slow to set into an acid-resistant mortar.

Abstract: Cementitious resin solutions for chemicals-resistant cements are prepared by dissolving a resin in furfuryl alcohol or preparing a resin solution by acidic condensation with the use of furfuryl alcohol. 0.01 to 0.1 equivalents of a primary amine per liter are added to the resin solution.

Abstract: Ammonium nitrilotrisulfonate is obtained by introducing nitric oxides into an aqueous ammonium sulfite solution at a pH of 5.0-7.5. The solution should contain at least 20 g/l of ammonium nitrilotrisulfonate in suspended form.

Abstract: Film-forming fire extinguishing foam concentrates are described containing water, at least one hydrocarbon surfactant and at least one fluorosurfactant compatible with the latter one, which comprise a small amount of aliphatic carboxylic acids of the formula C.sub.n H.sub.2n+1 COOH, in which n is an integer of from 7 to 9, or the salts thereof.

Abstract: Perfluoroethyl iodide is prepared from an agitated mixture of tetrafluoro-diiodoethane and hydrogen fluoride by means of electrolysis. Preferably the temperature is in the range of from -15.degree. C to +19.degree. C and the voltage in the range of from 4 to 6 V.