Abstract:
A component for detergents having the form of a gel comprises water in a weight percentage between the 70% and 95%; nanoparticles, preferably of amorphous silica or of aluminium hydroxide, of size between 5 and 250, in particular between 20 and 100 nanometres; selective anions selected from the group consisting of: HCO 3 -, CIO - , CH 3 COO - , OCO 2 O = , C 6 H 5 O 7 3- , CH 3 COOO-, adsorbed on the nanoparticles. By adding a certain an amount of gel to the conventional detergents, detergents are obtained that have lower critical micellar concentration (CMC) values, therefore a higher detergent power. By another point of view, the gel drastically reduces the presence of surfactants in the common detergents, while maintaining the detergent power, with the advantage of reducing the environmental impact and the production cost. A process to obtain this component provides mixing a water solution of a nanoparticles-forming compound, in particular silicate of Li, preferably Na or K, or a soluble aluminium salt with a pH higher than a minimum predetermined value, with a gelling agent configured to cause the pH to decrease, and amorphous silica or of aluminium hydroxide to precipitate, respectively said gelling agent selected from the group consisting of: chlorine; carbon dioxide; sodium hydroxide; a compound as a organic acid or inorganic, or a salt, soluble in water adapted to provide, starting from a concentration between 1N and 5N, a solution having pH lower than or equal to 9; and gelling the gelification mixture obtained forming a gel of nanoparticles that have a size set between 5 and 250 nanometres. The process provides also adsorbing said selective anions on the nanoparticles. The adsorption of the anions can be effected in situ during the mixing/gelling, in particular with a gelling agent as CO 2 and CI 2 adapted to releasing the selective anions, or it can be effected on an already formed gel.
Abstract:
A method for treating a waste material (20) containing sulfuric acid and metal ions, as In the case of the waste material the production of the T1O2, provides mixing to the waste material (20) an alkaline reagent (10), selected among a hydroxide of an alkaline metal such as Mg, Zn, Sn, adapted to selectively precipitate (300) the cations as hydroxides, thus obtaining a first mixture (21) having a higher pH that contains a solution (22) of a sulfate and/or oxysulfate of the metal and solid hydroxides (23) of the metal cations that are separated from the first mixture (21) and can be used in metal sulfates production process. The method also comprises mixing the solution (22) with a precipitation agent (31), thus forming a second mixture (32) in which the sulfate and/or oxysulfate precipitates and is removed (301), heated, reduced and decomposed (400) by means of a reducing agent (41) selected among elemental sulfur, hydrogen and a reducing flame, thus obtaining SO 2 (42) available for making H 2 SO 4 , and a solid oxide (43) of the metal of the alkaline reagent that is recycled (101) as alkaline reagent (10) in the step (200) of mixing with the waste material (20). Advantageously, a step (350) is provided of recovering precipitation agent (31) from the water of second mixture (32), after removing (301) the sulfate and/or oxysulfate, and a step (351) is also provided of recycling the regenerated precipitation agent (31), In particular, an alcohol as ethyl alcohol, used as the precipitation agent (31), can be easily regenerated by distillation, exploiting low temperature-heat, which is largely available from a possible sulfuric acid production plant close to the plant that producing the sulfuric waste material (20). The method according to the invention makes it possible to eliminate the sludge resulting from the sulfuric waste material treatment, while recovering valuable compounds.
Abstract:
The present invention relates to a salt with a reduced sodium content and a process for obtaining it that makes use of microwaves. The salt according to the present invention, obtained from sodium chloride and calcium gluconate, is characterised by a pleasant flavour and a high level of saltiness.