11 results about "Dithionite" patented technology

The invention discloses a selective gold extraction process by a thiosulfate method, which comprises the following steps of: adding gold ore and anion exchange resin into an aqueous solution of a leaching agent, and stirring and leaching to obtain ore pulp containing gold-loaded resin; the leaching agent comprises thiosulfate, copper salt and ammonia water; separating the gold-loaded resin from the ore pulp, and desorbing the gold-loaded resin by adopting a desorption agent to obtain a gold-rich desorption solution; and adding dithionite into the gold-rich desorption solution for reduction to obtain an elemental gold product. According to the process disclosed by the invention, resin adsorption and recovery are synchronously realized during gold leaching, and coadsorption of copper is avoided, so that gold can be enriched by adopting the gold-loaded resin through one-section desorption, and the gold extraction process flow is greatly simplified. In addition, the process is high in gold leaching rate, short in leaching time, low in agent consumption and low in leaching cost. In addition, the resin can be directly and circularly used for gold leaching without regeneration, the reduction barren solution can be circularly used for desorption of the gold-loaded resin by supplementing a small amount of desorption agent, and the recovery cost is low.

A polymer comprising pyridinium salt moieties, wherein the polymer has the following structure: In this structure, R1 and R6 are each N. At least a portion of R2 and R7 groups in the polymer are each negatively charged counterions selected from the group consisting of carboxylates, nitrates, nitrites, azides, metasilicates, tetraborate, perborates, boronates, oxalatob orates, metaborates, phosphorus-containing anions, halides, sulfates, SO4 -2, HSO4 -1, thiosulfate, dithionite, metabisulfite, persulfate, methanesulfonate, dioctyl sulfosuccinate, 3-sulfopropyl ethoxylate laurylphenyl ether, and combinations thereof. R3, R4, R8, R9, R11, R13, R14, R15, and R16 are each selected from the group consisting of H and groups including one or more carbon atoms. R5 and R10 are any group including one or more carbon atoms. The n is an integer from 2 to about 100,000.

A polymer comprising pyridinium salt moieties, wherein the polymer has the following structure: In this structure, R1 and R6 are each N. At least a portion of R2 and R7 groups in the polymer are each negatively charged counterions selected from the group consisting of carboxylates, nitrates, nitrites, azides, metasilicates, tetraborate, perborates, boronates, oxalatob orates, metaborates, phosphorus-containing anions, halides, sulfates, SO4 -2, HSO4 -1, thiosulfate, dithionite, metabisulfite, persulfate, methanesulfonate, dioctyl sulfosuccinate, 3-sulfopropyl ethoxylate laurylphenyl ether, and combinations thereof. R3, R4, R8, R9, R11, R13, R14, R15, and R16 are each selected from the group consisting of H and groups including one or more carbon atoms. R5 and R10 are any group including one or more carbon atoms. The n is an integer from 2 to about 100,000.

The present invention relates to a method for treating keratin fibers, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a post-treatment agent (N) to the keratin fibers, wherein the post-treatment agent (N) contains (N-1) at least one organic silicon compound from the group of silanes with one, two or three silicon atoms.

This invention provides a method for preparing an EGFR inhibitor intermediate (compound of formula V), using dithionite as a reducing agent to prepare compound V from compound IV; the preparation method has higher safety and is more conducive to industrial production.

The application discloses a method for treating dibenzene organic pollutants in water bodies, which comprises the following steps: electrolyzing wastewater to be treated and adding dithionite to carry out a redox reaction to obtain purified water; and the wastewater to be treated contains sodium chloride and dibenzene organic pollutants. The method for treating dibenzene organic pollutants in water bodies is carried out under normal temperature and pressure, is mild in reaction, is environmentally friendly, is easy to operate, is low in cost, has good degradation effect on dibenzene organic pollutants in the environment, and has great application potential in the field of environmental pollution treatment.

The present invention comprises methods and compositions for the treatment of contaminated groundwater and soil, or other media, with a mixture comprised of a sorbent, dithionite, and a pH controller.

The invention relates to a method for degrading melamino-formaldehyde resins from waste products produced during the production and processing of artificial panels, comprising the following steps: providing waste products which are produced during the production and processing of artificial panels and contain polycondensed melamino-formaldehyde resins; optionally, the waste material product containing the melamino-formaldehyde resin is crushed; mixing the waste product containing melamine formaldehyde resin with water and adding at least one reducing sulfur-containing compound selected from the group consisting of meta-disulfite, bisulfite and / or dithionite, sulfinate or sulfinate analogue; heating an aqueous mixture / suspension consisting of the waste product containing the melamine formaldehyde resin and at least one reducing sulfur-containing compound to a temperature of between 60 DEG C and 120 DEG C, preferably between 80 DEG C and 100 DEG C, with controlled reaction until a clear solution is obtained; separating impurities from the clear solution; optionally further heating the mixture of the waste product containing melamine formaldehyde resin and at least one reducing sulfur compound, from which impurities have been removed, at a temperature of between 60 DEG C and 120 DEG C, preferably between 80 DEG C and 110 DEG C under the condition of reaction control, and optionally at a temperature of between 60 DEG C and 120 DEG C, preferably between 80 DEG C and 110 DEG C, until it can be confirmed that the polycondensed melamine formaldehyde resin is not (re) present in the reaction mixture; and cooling the reaction mixture and separating the mixture of melamine derivatives precipitated in the process, in particular melamine hydroxymethyl alcohol and melamine sulfonate.

The present invention discloses a thiosulfate method for selective gold extraction, comprising the following steps: adding gold ore and anion exchange resin to an aqueous solution of a leaching agent for stirring and leaching to obtain a slurry containing a gold-loaded resin; the leaching agent comprises thiosulfate, a copper salt, and aqueous ammonia; separating the gold-loaded resin from the slurry, desorbing the gold-loaded resin using a desorbent to obtain a gold-rich desorbent; and adding dithionite to the gold-rich desorbent for reduction to obtain an elemental gold product. The process of the present invention simultaneously achieves resin adsorption recovery during gold leaching and avoids co-adsorption of copper. Therefore, the gold-loaded resin can be enriched in one-stage desorption, significantly simplifying the gold extraction process. Furthermore, the process has a high gold leaching rate, a short leaching time, low reagent consumption, and low leaching cost. Furthermore, the resin does not need to be regenerated and can be directly recycled for gold leaching. The reduced barren liquid, supplemented with a small amount of desorbent, can be recycled for desorption of the gold-loaded resin, resulting in low recovery costs.

The present invention discloses a flotation separation method for a copper-molybdenum mixed concentrate and a combined depressant used therein. The combined depressant comprises dithionite and thiobarbituric acid. The method involves adding dithionite to the copper-molybdenum mixed concentrate slurry for drug removal, then adding thiobarbituric acid to depress chalcopyrite, and then adding a molybdenite collector and a frother for flotation, thereby obtaining molybdenum and copper concentrates. The combined depressant is non-toxic and environmentally friendly, and the synergistic effect of the two depressants achieves excellent chalcopyrite inhibition at relatively low dosages, significantly improving molybdenum recovery and molybdenum-copper separation efficiency.

The invention discloses a method for treating dibenzo organic pollutants in a water body, which comprises the following steps: electrolyzing wastewater to be treated, adding dithionite, and carrying out oxidation-reduction reaction to obtain purified water; the wastewater to be treated contains sodium chloride and dibenzo organic pollutants. The method for treating the dibenzo organic pollutants in the water body is carried out under the conditions of normal temperature and normal pressure, is mild in reaction, environment-friendly, easy to operate, low in cost and good in degradation effect on the dibenzo organic pollutants in the environment, and has great application potential in the field of environmental pollution treatment.