70 results about "Chloride process" patented technology

The invention discloses a process for producing polyaluminum chloride by recycling aluminum ash. The process comprises a primary aluminum ash pretreatment process, a secondary aluminum ash deamination process, an ammonium chloride crystallization process, a liquid polyaluminum chloride process and a solid polyaluminum chloride process, the primary aluminum ash pretreatment procedure comprises a first cyclone separator, a ball mill, a screening machine and a bag-type dust collector, the input end of the first cyclone separator is connected with a primary aluminum ash bin through conveying equipment, the coarse ash end of the first cyclone separator is connected with a feeding port of the ball mill, and a discharging port of the ball mill is connected with a feeding port of the screening machine; fine powder screened by the screening machine and secondary aluminum ash fine powder discharged by the first cyclone separator are collected into a secondary aluminum ash bin, and dust outlets of the first cyclone separator, the ball mill and the screening machine are connected with a dust inlet of the bag-type dust collector through pipelines. By arranging a series of structures, the produced polyaluminum chloride is high in purity, the economic benefit of the process is improved, tail gas is washed, and the pollution is reduced.

The invention introduces a method for preparing artificial rutile by using reduced ilmenite, which comprises the following steps: S1, adding reduced ilmenite into a corrosion tank, introducing oxidizing gas to carry out corrosion reaction, and washing and separating the reaction product through a cyclone and a high-frequency sieve to obtain primary artificial rutile and hydrated iron oxide slurry; s2, carrying out filter pressing on the hydrated iron oxide slurry obtained in the step S1 by using a filter press, and preparing refined iron oxide from the obtained iron oxide slurry; s3, the primary artificial rutile obtained in the step S1 is washed and then subjected to a hydrochloric acid leaching reaction, a mixed material obtained after acid leaching enters a thickener, and supernatant returns to prepare an acid leaching solution; feeding lower-layer ore grains into a belt filter for deacidification and washing; and S4, drying the cleaned primary artificial rutile obtained in the step S3 through a drying cylinder to obtain the finished artificial rutile. Industrial hydrochloric acid is used as a rusting agent, and compared with ammonium chloride, the product Fe (OH) 3 can be separated more easily. Oxidizing gas used for rusting is mixed gas of air and pure oxygen, and the mixing proportion of the air and the pure oxygen can be dynamically adjusted according to different rusting raw materials, so that the reaction condition is in an optimal state. In the corrosion and acid leaching processes, the recycling efficiency of the liquid raw material is extremely high, and the prepared artificial rutile meets the requirements of a chlorination process titanium dioxide raw material. The whole process flow is reasonable in design, simple to operate, free of environmental pollution and easy for industrial production.

The chlorination process titanium dioxide oxidation reactor comprises a gas pipe, a combustion chamber and a front reaction cylinder which are sequentially connected, a front feeding cylinder is fixedly arranged in the front reaction cylinder through a partition plate, a radial front feeding opening is formed in the front reaction cylinder behind the partition plate, and the front feeding cylinder and the front reaction cylinder are arranged in a spaced mode in the radial direction; the rear end of the front reaction cylinder is fixedly connected with a rear charging cylinder; a cavity between the front charging cylinder and the front reaction cylinder is communicated with an inner cavity of the rear charging cylinder; a rear reaction cylinder is fixedly connected outside the middle of the rear feeding cylinder, a gap is formed between the rear reaction cylinder and the rear feeding cylinder on the radial inner side, a radial rear feeding opening is formed in the rear reaction cylinder, a cooling pipe is connected to the rear end of the rear reaction cylinder, and a cavity between the rear reaction cylinder and the rear feeding cylinder is communicated with an inner cavity of the cooling pipe; a coolant adding opening is formed in the cooling pipe; according to the utility model, twice reaction can be realized, a large amount of reaction heat after primary reaction is utilized, rock salt required by shock cooling is saved, the cost can be reduced, and the economic benefit is improved.

The invention provides a treatment method of chlorination process titanium dioxide solid waste residues, and belongs to the technical field of resources and environments. According to the method, the chlorination process titanium dioxide solid waste residues are dissolved and extracted step by step, high-value metal in the solid waste residues is recycled respectively, residual substances are evaporated and crystallized to obtain mixed salt, and zero emission and full resource utilization of the solid waste residues are achieved.

The invention relates to the technical field of synthesis of lithium ion battery materials, in particular to a method for preparing lithium manganese iron phosphate from chlorination process titanium dioxide waste acid and application. The method comprises the following steps: adjusting the pH value of the chlorination process titanium dioxide waste acid to 4.0-4.5, and then carrying out impurity removal reaction and first solid-liquid separation; adjusting the pH value of a mixed solution of the impurity-removed filtrate, a phosphorus salt and an oxidizing agent to 1.7-2.5, and then carrying out first reaction and second solid-liquid separation; adding phosphoric acid into the slurry of the amorphous iron phosphate filter cake, and then carrying out second reaction and third solid-liquid separation; mixing the iron-removed filtrate with an oxidizing agent, and carrying out third reaction and fourth solid-liquid separation; and adding phosphoric acid into the slurry of the manganese oxyhydroxide filter cake, and then carrying out fourth reaction and fifth solid-liquid separation. According to the method, ferrous chloride and manganous chloride in the chlorination process titanium dioxide waste acid are used for preparing lithium iron manganese phosphate, the production cost is reduced, the problem that a large number of solids are generated by neutralizing the waste acid and occupy land easily is solved, and iron and manganese resources are fully utilized.

The invention provides a method for treating chlorination furnace tail gas in chlorination process titanium dioxide production, which is characterized in that primary filtrate obtained by dissolving dust collection slag generated by a chlorination furnace with water and then filtering is used for selectively absorbing chlorine in the chlorination furnace tail gas, the concentration percentage of Fe < 2 + > in the primary filtrate is 0.5%-12%, the concentration percentage of HCl is 0.1%-10%, and the concentration percentage of Cl is 0.1%-10%. Ferric chloride and chlorine in the primary filtrate react to generate ferric trichloride, chlorine in the tail gas of the chlorination furnace is removed, meanwhile, the primary filtrate is acidic and is prevented from reacting with carbon dioxide contained in the tail gas of the chlorination furnace to generate low-solubility carbonate, the output of waste is reduced, and the production cost is reduced. The problem that low-solubility carbonate generated in the chlorine gas absorption process through traditional alkali washing is separated out in a leaching tower and a pipeline, and consequently the leaching tower and the pipeline are blocked is solved. Meanwhile, the waste liquid is recycled, the treatment cost of the tail gas of the chlorination furnace is reduced, the ferric chloride solution generated after the chlorine gas is absorbed by the primary filtrate can be recycled, and the subsequent environmental protection problem is avoided.

The invention relates to a preparation method of a titanium dioxide pigment with low surface hardness, which comprises the following steps: producing a titanium dioxide primary product by adopting a chlorination process, pulping in de-ionized water, preparing into slurry, adding a water-soluble silicate solution as a dispersing agent, curing, and grinding. The slurry is heated, and the whole coating process is carried out at the temperature. The surface of titanium dioxide is coated with a layer of loose magnesium silicate at a certain pH value by adopting water-soluble magnesium salt and silicate, so that the surface hardness of titanium dioxide is reduced while the product has high dry covering and excellent weather resistance on blocking photochemical active points on the surface of titanium dioxide, thereby reducing the abrasion to related products and processing equipment. The titanium dioxide pigment prepared by the method not only has high dry covering power, but also has low surface hardness, and is particularly suitable for being applied to the fields of ink-jet ink and chemical fiber products.

The invention relates to a method for treating a residue obtained from the chloride process, wherein the residue comprises the components titanium dioxide, coke, an inert metal oxide, and an iron-containing component. Further, the invention refers to the use of this method to separate the components contained in said residue, and to the use of the separated components in the chloride process for obtaining titanium dioxide.

The invention relates to the technical field of chlorination-process titanium dioxide production, in particular to a chlorination-process titanium dioxide particle size control method which comprises the following steps: mixing hot oxygen, aluminum trichloride and preheated titanium tetrachloride in an oxidizing furnace, and reacting to obtain primary titanium dioxide particles; the pressure of the tail of the oxidizing furnace is controlled to be 180-400 kPa, so that the pressure of the furnace end is controllable within the range of 280-500 kPa, and target regulation and control of the particle size of the primary titanium dioxide particles within the range of 160-350 nm are achieved by controlling the pressure of the system. According to the method, the particle size of the primary titanium dioxide particles can be efficiently and quickly controlled within the range of 160-350 nm.

This invention discloses a method for recovering gallium-vanadium enriched material from gallium-vanadium-containing solid waste. The method includes: mixing the gallium-vanadium-containing solid waste with waste acid, stirring and leaching under heating conditions to obtain a slurry; wherein the waste acid is selected from waste hydrochloric acid, a byproduct of titanium dioxide extraction tail gas treatment during the chloride process, or waste sulfuric acid formed after drying chlorine gas with concentrated sulfuric acid during the chloride process; adding a neutralizing agent to the slurry to adjust the pH value to 0.3±0.1, filtering to obtain a first filtrate; adding a reducing agent to the first filtrate to reduce the trivalent iron and pentavalent vanadium in the solution, filtering to obtain a second filtrate; adjusting the pH value of the second filtrate to 3.8-4.5 with an alkaline precipitant to carry out a precipitation reaction, and obtaining gallium-vanadium enriched material after solid-liquid separation. This invention achieves simultaneous enrichment of gallium and vanadium, simplifying the process flow, reducing operational difficulty and production costs, while obtaining high-grade gallium-vanadium enriched material.

The invention provides a treatment method of a titanium dioxide primary product slurry in a chlorination process titanium dioxide process, which comprises the following steps: feeding a titanium dioxide primary product produced by a chlorination process into water in a beating tank, mixing to obtain a mixture, adding hydrogen peroxide, and continuously mixing to obtain a slurry; washing and filter-pressing the slurry obtained in the previous step to obtain a filter cake; and mixing the filter cake obtained in the previous step with water, and adding a pH regulator to obtain the pulped titanium dioxide slurry. The method can ensure that the viscosity of the slurry is relatively low, meets the requirements of a sanding process, does not need to additionally add a dispersing agent, reduces the consumption of hydrogen peroxide and caustic soda flakes, thoroughly cleans sodium and chloride ions in a titanium dioxide chloride primary product, reduces the ion concentration in the titanium dioxide slurry, solves the problems of high pulping viscosity and poor sanding effect, reduces the sanding cost, and improves the production efficiency. The product quality is improved to a certain extent, and the problem that the content of impurity elements in titanium dioxide is unstable can be avoided.

The invention relates to a preparation method of a glass fiber reinforced modified plastic titanium dioxide pigment. The method comprises the following steps: producing a rutile type titanium dioxide primary product by adopting a chlorination process, and pulping to prepare slurry; adjusting the pH value by using inorganic acid or alkali, adding a silane coupling agent for curing within a certain time, adding high-molecular siloxane for curing, and curing the cured slurry to form a layer of uniform and transparent siloxane elastomer on the surface of titanium dioxide; and adding a silane coupling agent through steam powder to finally form the product. The titanium dioxide pigment prepared by the method not only has excellent covering power, whiteness, weather resistance and the like of titanium dioxide, but also has the characteristics of low hardness and low plastic product processing difficulty of zinc sulfide, and is suitable for being used in products with high weather resistance requirements of glass fiber reinforced modified plastic outdoor systems.

This invention discloses a causal modeling optimization method, electronic device, and storage medium for the chloride process titanium dioxide production process based on a neural network surrogate model. The method includes acquiring and normalizing preprocessing data of the chloride process titanium dioxide production process; using recursive feature elimination based on cross-validation to obtain confounding factor features strongly correlated with the target output; training a surrogate model using the obtained feature data to predict the potential effects of each manipulated variable on the target output; and calculating the causal benefits through the potential results output by the surrogate model. This invention reduces the computational cost of causal modeling for complex chloride process titanium dioxide production processes, and can efficiently evaluate the causal benefits of manipulated variables when the system model is unclear or system parameters are lacking, providing a scientific basis for auxiliary decision-making and fault diagnosis in the chloride process titanium dioxide production process.

The invention discloses a method and a system for determining the content of calcium and magnesium in an ammonia chloride process electrolytic zinc solution, and the method comprises the following steps: in a solution of which the pH value is equal to 10, taking sodium potassium tartrate tetrahydrate and triethanolamine as masking agents, taking acid chrome blue K-naphthol green B as an indicator, and titrating with EDTA until pure blue, so as to determine the content of calcium and magnesium; in a strong alkaline solution with a pH value of more than 12, triethanolamine is used as a masking agent, a calcium indicator is used as an indicator, EDTA is used for titration until pure blue is used as an end point, the calcium content is determined, the content of calcium and magnesium in an ammonia chloride process electrolytic zinc solution can be accurately determined, the method is used for guiding a production raw material formula, and calcium and magnesium in the solution are timely removed so as to avoid serious influence on production.

This invention relates to the field of pigment preparation, specifically to a method for preparing highly conductive titanium dioxide using the chloride process. The method includes: reacting oxygen and titanium tetrachloride with an oxidation reaction to generate titanium dioxide particles, which are then introduced into a cooling conduit. A preheated coating agent is added for a coating reaction and slurry preparation. The slurry temperature is adjusted to 60-75°C and the pH to 2-3, and a phosphate-containing compound is added. The slurry temperature is adjusted to 80-90°C, and a sodium aluminate solution and an alkaline solution are added to adjust the pH of the slurry to 9.5-10.5, followed by a first homogenization treatment. A tin chloride solution and a sodium aluminate solution are added, and the pH of the slurry is adjusted to 7.5-8.5, followed by a second homogenization treatment. The pH of the slurry is adjusted to 4.5-5.5, followed by a third homogenization treatment. The pH of the slurry is adjusted to 5.5-6.5, followed by a fourth homogenization treatment. This method is low-cost, simple, and suitable for large-scale production, producing conductive titanium dioxide with excellent performance.

A device and method for efficient clean utilization of fluor carbon cerium ore double chlorination method, relate to the field of rare earth comprehensive utilization and recovery, the device is composed of a first continuous packing bed, pipeline device; second continuous packing bed; third continuous packing bed; first screw propelling type condenser; second screw propelling type condenser. Rare earth concentrate is chlorinated with aluminum chloride, carbon monoxide and chlorine gas generated in the first and second continuous packing beds in the third continuous packing bed. Chlorinated rare earth, aluminum fluoride and alkaline earth metal chlorides generated by chlorination reaction remain in the chlorination slag in solid form, and titanium tetrachloride, silicon tetrachloride and iron chloride leave the chlorination furnace in gaseous form. The gaseous chlorination products are condensed and recovered by the screw propelling type condenser. The solid phase products are separated by water immersion to obtain single rare earth chloride. The present application realizes the comprehensive utilization of rare earth elements and associated elements such as titanium, fluorine, silicon and iron in fluor carbon cerium ore, and no acid and alkali waste liquid and wastewater are generated in the reaction process, which has good environmental benefits.

The invention relates to a preparation method of slurry with high purity and high titanium dioxide content. The method comprises the following steps: carrying out oxidation reaction by taking semi-finished titanium dioxide produced by a chlorination process and refined titanium tetrachloride subjected to vanadium removal and silicon removal as raw materials; in the oxidation reaction, no reaction auxiliary agent is added, and crystal form transformation is realized only by reaction temperature, pressure and retention time; zirconium beads are added into the reacted titanium dioxide gas-solid mixture, heat exchange cooling is promoted, and the particle size and the temperature are controlled; separating by a bag filter, adding water or desalted water into the collected titanium dioxide, pulping, properly dispersing, filtering and washing, and removing soluble metal salt and other impurities; adding desalted water for pulping after washing and filter pressing, controlling the concentration of the pulp, adding a dispersing agent, a mildew preventive and a defoaming agent, and packaging. The chlorination process semi-finished product titanium dioxide and impurity-removed refined titanium tetrachloride are used as raw materials, impurities are reduced from the source, oxidation is free of auxiliaries, side reaction is avoided, purity is guaranteed, slurry conductivity is controlled through multi-round pulping and washing, and the requirement of the market for high-purity and high-titanium-dioxide-content slurry is met.

The invention discloses a method for preparing nano titanium dioxide by using chlorination process titanium dioxide waste acid. The method comprises the following steps: performing membrane separation and impurity removal on the titanium dioxide waste acid; selectively extracting Sc and V to obtain enriched liquid; selectively extracting iron ions in the enrichment liquid to obtain a titanium solution and a strip liquid; performing reverse osmosis concentration on the titanium solution to obtain a concentrated solution; performing microwave-assisted hydrolysis on the concentrated solution to obtain a precursor; the precursor is subjected to calcination treatment, and anatase type nano titanium dioxide is obtained; moreover, the particle size of the anatase type nano titanium dioxide is 10-100 nm, and the content of an anatase phase is greater than or equal to 80% by mass. According to the method, the titanium recovery rate is larger than 95%, rare metals such as Sc and V are synchronously recovered, and efficient recovery of resources is achieved; the nano TiO2 can be used in the fields of photocatalysis, new energy and the like, and the added value of the product is relatively high; the heavy metal content is low after waste acid treatment, the circular economy mode of treating waste with waste is achieved, and the method is environmentally friendly and has good popularization prospects.

The present invention discloses a method for separating, recovering and utilizing the coke black slag of chloride process titanium dioxide ore, comprising the following steps: S1. Adding water to the coke black slag of chloride process titanium dioxide ore and stirring to make a slurry; S2. Adding flotation reagents and bubbling with compressed air to the slurry at a feeding rate of 15-20 m<supgt;3< / supgt> / h, and sequentially passing through 4-stage flotation separation to obtain coking foam and bottom product in the cell. The coking foam in the 1st to 4th stages is collected and combined, and after filtration and drying, carbon concentrate is obtained. The bottom product in the 1st to 3rd stages is transported to the next stage of flotation; S3. Separating the ore belt from the bottom product in the 4th stage through 2-stage shaking table to obtain titanium concentrate and iron tailings. The method provided by the present invention is simple and conducive to popularization, is a very clean production process, will not cause pollution to the environment, completely solves the problem of the outlet of the solid waste coke black slag in the chlorination furnace during the production of chloride process titanium dioxide, and moreover, the obtained product can also serve the chloride process titanium dioxide process itself, realizing the maximum utilization of energy.

Integrated processes and systems for the co-production of titanium dioxide and caustic soda. A chlor-alkali process is integrated with a chloride process of titanium dioxide production to produce both caustic soda and titanium dioxide. A chlor-alkali unit produces caustic soda, chlorine, and hydrogen. The chlorine produced in the chlor-alkali unit then serves as an input for a titanium dioxide production unit. Some or all of the hydrogen is combusted to generate the heat required for the titanium dioxide production unit, and / or used in other processes, such as a reducing agent in the production of direct reduced iron (DRI).

The application provides a method for controlling the particle size of titanium dioxide primary product in a chlorination process, which comprises the following steps: high-temperature O2 enters an oxidation reactor through a combustion chamber, and TiCl4 vapor enters the oxidation reactor through a TiCl4 feeding ring; the high-temperature O2 and the TiCl4 vapor react in a mixing reaction zone of the oxidation reactor to generate TiO2 powder; CsCl particles are sprayed into the oxidation reactor at the rear end of the feeding ring adjacent to the oxidation reactor; at least one magnetic field is applied to the mixing reaction zone and / or a cooling conduit, and the magnetic field parameters are set according to the target particle size of the titanium dioxide primary product. The application also provides a method for removing scars of an oxidation reactor for titanium dioxide in a chlorination process. The application also provides a device for controlling the particle size of titanium dioxide primary product in a chlorination process. The method of the application effectively solves the problem of scarring of the furnace wall from the rear end of the feeding ring to the high-temperature reaction core area of the oxidation reactor, and the average particle size of the titanium dioxide primary product produced reaches 180-260 nm, the purpose of optimizing the particle size distribution is achieved, and thus the quality of the titanium dioxide primary product in the chlorination process can be stabilized.

The invention relates to the technical field of titanium dioxide production, in particular to a method for increasing the concentration of chlorination process titanium dioxide sanding slurry, which comprises the following steps: adjusting the pH value of deionized water to 13.0-14.0 by using an alkaline compound, and adding a certain amount of ethanol to obtain an alkaline ethanol aqueous solution; mixing the alkaline ethanol aqueous solution, a dispersing agent and the chlorination process titanium dioxide primary product to obtain pre-sanding slurry; and adding zirconium beads into the pre-sanding slurry for sanding dispersion, and screening to obtain the sanding slurry. By controlling the mass ratio of the ethanol to the deionized water, the mass ratio of the chlorination process titanium dioxide primary product to the ethanol aqueous solution, the pH value of the slurry before sanding and the like, the concentration and dispersion stability of the slurry after chlorination process titanium dioxide sanding can be improved, so that the titanium dioxide film layer after inorganic coating is more uniform, and the pigment performance and application performance of the titanium dioxide product are ensured. In addition, according to the method, the material mixing time before sanding dispersion can be shortened while the sanding dispersion effect is guaranteed, and the production efficiency is improved.

The invention provides a method for extracting a vanadium element from chlorination process titanium dioxide dust collection slag, and belongs to the technical field of resources and environments. The method comprises the following steps: mixing the chlorination process titanium dioxide dust collection slag, a reducing auxiliary agent, acid and water to obtain acidic mixed slurry; the acid environment can inhibit interference of hetero-ion precipitation, pentavalent vanadium of the chlorination process titanium dioxide dust collection slag can be converted into tetravalent vanadium, the selectivity of vanadium during extraction is improved, and then the recovery efficiency of vanadium is improved. The leaching solution and the compound organic phase are mixed for extraction, an alcohol solvent or a neutral organic phosphorus extraction agent in the extraction improver in the compound organic phase can prevent the emulsification phenomenon during extraction, phase splitting is facilitated, and the vanadium extraction effect is improved. According to the method, the vanadium-containing strip liquor is mixed with the oxidizing agent and the ammonium salt, ammonium metavanadate precipitates or ammonium polyvanadate precipitates are obtained during oxidation and vanadium precipitation, and then a vanadium product is obtained.

The invention relates to the technical field of metallurgy, in particular to an anosovite reconstruction method for a chlorination process titanium dioxide oxidation unqualified primary product and anosovite, and the reconstruction method comprises the following steps: step 1, dechlorinating the chlorination process titanium dioxide oxidation unqualified primary product to obtain a first mixture; 2, the first mixture and petroleum coke are mixed, ground and smashed, and a second mixture is obtained; 3, adding a solvent into the second mixture to obtain a third mixture; 4, the third mixture is subjected to heat preservation for a first time at the first temperature, and a melt is obtained; and step 5, cooling the melt to room temperature by adopting gradient cooling to obtain anosovite. According to the reconstruction method disclosed by the invention, the problems of resource waste and low grade rate caused by unqualified primary products produced due to factors such as starting and stopping in the current production process are effectively solved.

This invention belongs to the technical field of metal ion adsorption materials, specifically a method for preparing an adsorbent and a method for determining the soluble zinc content of raw materials used in the ammonia chloride process for producing electrolytic zinc. This invention modifies the surface of manganese dioxide with a thiourea-based silane coupling agent, grafting a silane coupling agent containing a thiourea structure onto the surface of manganese dioxide. The adsorption of lead, copper, and cadmium ions in solution is achieved using the manganese dioxide matrix and the thiourea-based silane coupling agent on the matrix surface, while effectively preventing the adsorbent from adsorbing zinc ions from the solution. When the adsorbent prepared by this invention is used to determine the soluble zinc content of raw materials used in the ammonia chloride process for producing electrolytic zinc, it exhibits a small testing error and can effectively improve the accuracy of soluble zinc content determination.

The utility model provides a cooling conduit and relates to the technical field of titanium dioxide production by a chlorination method. A cooling guide pipe comprises a main body pipe, a first heat dissipation assembly and a second heat dissipation assembly are alternately arranged on the annular side of the main body pipe in the axial direction, the first heat dissipation assembly comprises a plurality of first cooling fins, the second heat dissipation assembly comprises a plurality of second cooling fins, and the central axis of any second cooling fin is located between the central axes of every two adjacent first cooling fins. The multiple first cooling fins and the multiple second cooling fins are all used for cutting the cooling liquid on the outer side of the cooling guide pipe. The utility model provides a cooling guide pipe which can improve the heat dissipation effect of the cooling guide pipe.

The invention relates to the technical field of chlorination process titanium dioxide production waste residue and waste gas recovery, in particular to a synergistic resource recovery method and system for FeCl2 waste residue and Cl2-containing tail gas. Comprising the following steps: S1, mixing FeCl2-containing waste residues with water and a dispersing agent to prepare slurry, so as to obtain FeCl2 slurry; s2, the Cl2-containing tail gas and FeCl2 slurry are subjected to countercurrent contact reaction, and FeCl3 slurry is obtained; s3, the FeCl3 slurry is subjected to impurity removal and filtration to obtain a FeCl3 solution, and then the FeCl3 solution is subjected to spray drying to obtain FeCl3. 6H2O microspheres; and S4, carrying out fluidized bed roasting on the FeCl3. 6H2O microspheres by using a mixed gas containing O2 and water vapor to obtain the alpha-Fe2O3 pigment, and recycling the released chlorine after adsorption and purification by a molecular sieve. According to the method, the chlorine element and the iron element can be efficiently recovered at the same time, the cyclic utilization rate of the chlorine element reaches 88%, and meanwhile high-alpha-phase iron oxide is obtained.

The present invention relates to a method for recovering chlorine from hydrogen chloride produced by a carbon chlorination method. Further, the present invention relates to the use of this method for recovering chlorine from hydrogen chloride produced by a carbon chlorination method.

The invention provides a method for recovering titanium and high-quality hydrochloric acid from titanium-containing waste hydrochloric acid, and belongs to the technical field of clean energy and environment-friendly recovery. The titanium element and the high-purity hydrochloric acid in the waste acid are extracted and recycled through the composite extraction agent, the extraction effect is greatly improved by optimizing the types of the extraction agent and the stabilizer in the composite extraction agent, and the number of stages of extraction is reduced; after raffinate obtained after single-stage extraction is subjected to reverse extraction through a soluble alkali solution and / or a soluble salt solution, a water phase is subjected to simple filter pressing, a carbon dioxide recycled material and high-quality hydrochloric acid can be obtained, and the extraction rate of Ti in the titanium-containing waste hydrochloric acid is gt; the HCl recovery rate is gt; and 98%. According to the technology, comprehensive resource utilization of the titanium-containing waste acid generated in the process of producing titanium dioxide through a chlorination method is achieved, the comprehensive recovery value of the titanium-containing waste hydrochloric acid is increased through high-yield recovery of the titanium element and hydrogen chloride, environmental pollution and resource waste are effectively reduced, and remarkable economic and ecological environment benefits are achieved.

The present invention relates to the technical field of waste acid recycling, and more specifically, to a method for preparing ferric phosphate using waste acid from titanium dioxide produced by the chloride process, and its application. The method comprises: adding an alkaline slurry to the waste acid from the chloride process to carry out an aluminum-chromium removal reaction; after the aluminum-chromium removal reaction reaches a pH of 3.8 to 4.5, performing solid-liquid separation to obtain a filtrate; mixing the filtrate with an oxidant and conducting an oxidation reaction; then adding an alkaline slurry to the waste acid to carry out a precipitation reaction; after the precipitation reaction reaches a pH of 2.5 to 4.0, performing solid-liquid separation to obtain a main filter cake; adding a phosphoric acid solution to the filter cake, adjusting the pH of the mixture to 3.0 to 3.5, performing an ferric phosphate synthesis reaction, and after the ferric phosphate synthesis reaction is complete, performing solid-liquid separation to obtain ferric phosphate. This method not only provides qualified raw materials for ferric phosphate production, but also achieves the reuse of waste acid from titanium dioxide produced by the chloride process.