12results about "Hydrogen chloride preparation" patented technology

This invention provides a production process for manufacturing metallic magnesium and industrial silicon by decomposing serpentine using the hydrochloric acid method. [Solution] The present invention provides a method for processing serpentine ore as a raw material using a two-stage countercurrent hydrochloric acid leaching process. The wet process steps include storage and filtration of the slurry after ore dressing, two-stage hydrochloric acid leaching under atmospheric pressure, washing and filtration of the silicon slag after leaching, removal of iron and nickel precipitation from the leaching solution, separation, washing and filtration of the obtained iron hydroxide and nickel hydroxide, crystallization and evaporation of the magnesium chloride solution, and production of hydrochloric acid using the gas generated after the thermal decomposition of magnesium chloride. The present invention has developed a serpentine decomposition technology using hydrochloric acid, a metallic magnesium production process using a drying-electrolytic method, and a process for producing industrial silicon by smelting silicon slag in an electric furnace.

The invention discloses a chloride solution electrolysis recycling method in a metal smelting separation process, which is characterized in that a metal chloride solution and a sodium chloride solution which are obtained in the metal smelting separation process, and a sodium hydroxide solution and hydrochloric acid which are prepared by an electrolysis method are recycled in the metal smelting separation process. CO2 generated in the roasting process is recycled to be circularly used in the metal carbonization precipitation process, material recycling in the smelting separation process is achieved, the technology is good in applicability, and the common problems that in the industry at present, waste water tail end treatment is high in energy consumption and cost, and materials are difficult to recycle are solved.

The present invention provides a method (100a) and system for controlling the operation of a chemical plant arranged to carry out a chemical process which produces iron and / or manganese in elemental form from respective oxides thereof using liquid sodium as a reductant of the respective oxides and which can also produce an oxide or hydroxide of at least one of calcium, magnesium and iron from a carbonate mineral of at least one of calcium, magnesium and iron. The method (100a) comprises assigning (103a) a respective value to the no. of mol of each one of the chemical species involved in the chemical process as starting materials and products thereof, subject to constraints which are derived from the law of conservation of mass of the constituent elements of those chemical species. The method also assigns (103b) respective values to the nos. of mol of chemical species which are consumed during the chemical process by electrolytic or thermochemical decomposition into their constituent elements, subject to another set of constraints which are derived from the minimum requirements for these constituent elements by the chemical process itself. The former set of constrains allows the materials balance of the process to be controlled and the latter set of constraints allows the energy balance of the process to be controlled. The method then comprises operating (104) the chemical plant to carry out the process according to the values thus assigned. Respective values may be assigned (103a, 103b) to the nos. of mol of a preferred subset of the chemical species involved in the process as starting materials and products thereof and / or a preferred subset of the chemical species which are consumed during the process by electrolytic or thermochemical decomposition into their constituent elements, before values are then assigned to remaining ones of the nos. of mol of other chemical species not in the preferred subset. This allows the chemical plant to be operated in such a way as to optimise its performance relative to such variables as the respective nett amounts of a preferred one or more of the materials it consumes and / or produces, the energy efficiency of a part or the whole of the chemical process and / or its cost effectiveness, for example. Amongst other things, the constraints also ensure that the chemical process always produces less carbon dioxide than instead calcining a carbonate mineral of at least one of calcium, magnesium and iron to produce its corresponding oxide, and that in a large number of cases, it can produce no carbon dioxide at all. Also disclosed is a graphical technique which may be used to assign the respective values to the nos. of mol of the chemical species involved in the chemical process subject to the stated constraints, whereby the method and system of the invention may be implemented.

Processes for treating spent caustic in a hydrocarbon process utilizing HCl are described. The processes include sending the spent caustic to a caustic scrubbing system. HCl rich off gases are routed to the scrubbing system. This process is designed to deplete the NaOH in the spent caustic and form a brine solution. The brine is sent to an electrochemical cell to convert the NaCl to NaOH while generating chlorine and hydrogen gas. The NaOH generated from the electrochemical reaction is recycled back to the caustic scrubber, while the chlorine and hydrogen gas are combined and recycled back to the reaction zone.

The invention provides a method and system for removing zinc and extracting zinc from chlor-alkali coupled galvanized waste, and the method for removing zinc and extracting zinc from chlor-alkali coupled galvanized waste comprises the following steps: driving chlor-alkali equipment with green electricity, electrolyzing a sodium chloride solution to prepare hydrogen, chlorine and a sodium hydroxide solution, and synthesizing hydrochloric acid from the hydrogen and chlorine from the chlor-alkali equipment under a heating condition; pickling and soaking the zinc plating waste by using the synthesized hydrochloric acid to obtain a chloride solution and hydrogen; performing multiple-effect evaporation on the chloride solution to obtain a concentrated solution and diluted hydrochloric acid, and reusing the diluted hydrochloric acid for pickling and soaking; performing fractional precipitation on the concentrated solution by using a sodium hydroxide solution from chlor-alkali equipment, and separating zinc hydroxide precipitate and waste liquid; performing heat treatment on the separated zinc hydroxide precipitate to obtain zinc oxide; hydrogen generated by pickling and soaking is used for reducing zinc oxide hydrogen, and zinc metal with the purity larger than 99% is obtained; sodium chloride and sodium hydroxide in the waste liquid obtained through fractional precipitation are recycled, sodium chloride is recycled to chlor-alkali equipment, and sodium hydroxide is recycled to fractional precipitation.

Methods and systems for production of lithium hydroxide and lithium carbonate are described. One or more embodiments of the method include producing lithium hydroxide from potassium chloride, lithium chloride, and water. One or more embodiments of the method include producing lithium carbonate from potassium chloride, lithium chloride, water, and a carbon dioxide source. One or more embodiments of the method include producing lithium carbonate from sodium chloride, lithium chloride, water, and a carbon dioxide source.

A method for preparing metallic magnesium and industrial silicon by decomposing serpentine with hydrochloric acid is provided. Serpentine is used as a raw material, and is processed by a two-stage countercurrent leaching process in a hydrochloric acid system. A hydrometallurgical process is adopted, including beneficiation, wet grinding, slurry storage, filtration, two-stage atmospheric pressure hydrochloric acid leaching, washing and filtration of leached silica slag, iron removal and nickel precipitation from a leachate, separation, washing and filtration of a ferric hydroxide precipitate and a nickel hydroxide precipitate, crystallization and evaporation of a magnesium chloride solution, and hydrochloric acid preparation from a flue gas generated after thermal decomposition of magnesium chloride. The present disclosure develops a process of decomposing serpentine with hydrochloric acid and producing metallic magnesium by a drying-electrolysis method, and a process of producing industrial silicon by smelting silica slag in an electric furnace.

A method for preparing metallic magnesium and industrial silicon by decomposing serpentine with hydrochloric acid is provided. Serpentine is used as a raw material, and is processed by a two-stage countercurrent leaching process in a hydrochloric acid system. A hydrometallurgical process is adopted, including beneficiation, wet grinding, slurry storage, filtration, two-stage atmospheric pressure hydrochloric acid leaching, washing and filtration of leached silica slag, iron removal and nickel precipitation from a leachate, separation, washing and filtration of a ferric hydroxide precipitate and a nickel hydroxide precipitate, crystallization and evaporation of a magnesium chloride solution, and hydrochloric acid preparation from a flue gas generated after thermal decomposition of magnesium chloride. The present disclosure develops a process of decomposing serpentine with hydrochloric acid and producing metallic magnesium by a drying-electrolysis method, and a process of producing industrial silicon by smelting silica slag in an electric furnace.

Disclosed in the present invention is a method for recycling a chloride solution from a metal smelting separation process by means of electrolysis. A metal chloride solution and a sodium chloride solution obtained from a metal smelting separation process are recovered, a sodium hydroxide solution prepared by means of an electrolysis method and hydrochloric acid are recycled for the metal smelting separation process, and CO2 generated in a roasting process is recovered and is cyclically used in a metal carbonization and precipitation process, thereby achieving the recycling of the materials from the smelting separation process. Moreover, the technique has good applicability, and solves problems common in the industry at present, such as the high energy consumption and costs of the end-of-pipe treatment of wastewater, and difficulties in material recycling.

A method by which an environmental energy (e.g., wave energy) is harvested, converted into electrical power, and thereafter used to electrolyze seawater into hydrogen and chlorine gases. Those gases are recombined into hydrogen chloride from which is formed hydrochloric acid solution which is diluted and deposited at a depth sufficient to ensure its neutralization and sequestration for a significant period of time (e.g., for over a millennium). By removing chloride ions from a portion of the sea adjacent to its upper surface and depositing them into a portion of the sea more adjacent to its bottom, acidity is shifted from the surface to base of the sea, and the surface ocean is given a greater ability to absorb and buffer atmospheric carbon dioxide without a corresponding increase in acidity.

The invention relates to the technical field of chlorinated polyethylene production, and discloses a chlorinated polyethylene chlorine introduction reaction automatic control production method, which comprises the following steps: by using 17% hydrochloric acid as a suspension medium, putting the 17% hydrochloric acid into a reaction kettle, adding an auxiliary agent into an acid phase to suspend high density polyethylene powder in the acid phase, introducing steam into a jacket of the reaction kettle, and reacting for 2-3 hours; raising the temperature of the material, and starting to introduce chlorine to carry out substitution reaction when the temperature reaches the process temperature; in the reaction process, heat is released continuously; and removing acidic substances from the material after the reaction is finished, feeding the material after deacidification and alkali neutralization into a continuous discharging boiling fluidized drying bed for drying, and obtaining the chlorinated polyethylene resin after drying. According to the chlorinated polyethylene chlorine introduction reaction automatic control production method, the labor intensity of operators is reduced, and the defects that in the chlorinated polyethylene production process, the automation degree is not high, manual operation is mainly adopted in a production field, labor consumption is large, and operation is unstable are overcome.

Processes for treating spent caustic in a hydrocarbon process utilizing HCI are described. The processes include sending the spent caustic to a caustic scrubbing system. HCI rich off gases are routed to the scrubbing system. This process is designed to deplete the NaOH in the spent caustic and form a brine solution. The brine is sent to an electrochemical cell to convert the NaCI to NaOH while generating chlorine and hydrogen gas. The NaOH generated from the electrochemical reaction is recycled back to the caustic scrubber, while the chlorine and hydrogen gas are combined and recycled back to the reaction zone.