Abstract:
Silicic acid sols are treated with a mixture of trivalent metal salts and bivalent metal salts which react to form metallic oxide coatings on the surface of the sol particles. The sols as a result are rendered more stable, as indicated by the fact that the viscosity of said sols remains constant and the tendency to gel is eliminated. The sols can be dried to give a finely divided product.
Abstract:
Under the latest clean-air legislation, processes for flue gas desulphurisation must be developed which operate at low costs, reach high degrees of purification and do not cause any secondary waste. In such a process, the hot flue gases are scrubbed in a first stage with 10 to 50% sulphuric acid and, in a second stage, the flue gases cooled to 100 to 170 DEG C are again treated with 10 to 50% sulphuric acid to which hydrogen peroxide has been admixed.
Abstract:
Sludge, especially sewage sludge is deodorized, particularly to obtain the biomass by treating the waste water sludge (pollution sludge) with an active oxygen developing compound at 5 DEG to 40 DEG C.
Abstract:
Sludge, especially sewage sludge is deodorized, particularly to obtain the biomass by treating the waste water sludge (pollution sludge) with an active oxygen developing compound at 5 DEG to 40 DEG C.