79 results about "Raffinate" patented technology

A method of recovering a nickel, cobalt, and manganese salts includes removing impurities from an acidic aqueous leach solution including cobalt, manganese, and nickel salts to produce a purified aqueous solution including the metal salts and remaining impurity salts. The method includes extracting the purified aqueous solution in a first liquid-liquid extraction step using a first organic extractant to produce a first aqueous raffinate solution including the cobalt, manganese, and nickel salts and a first loaded organic solution including one or more of the remaining impurity salts from the purified aqueous solution. The method further includes extracting the cobalt, manganese, and nickel salts from the first aqueous raffinate solution in a second liquid-liquid extraction step using a second organic extractant to produce a second loaded organic solution including the cobalt, manganese and nickel salts and a second aqueous raffinate solution comprising one or more of the remaining impurity salts.

The disclosure relates to a continuous process for obtaining phosphoric acid and calcium sulphate dihydrate from apatite, and sulphuric acid using hydrochloric acid as an intermediate attacking agent, comprising the steps: Leaching (101) apatite (11) with an aqueous solution of hydrochloric acid (12,13) to solubilize phosphorus compounds contained in the apatite, thereby obtaining a solution (15) containing phosphate (H3PO4) and calcium chloride (CaCl2); extracting (103) said solution (15) with organic solvent (16), yielding an organic extract (17) loaded with phosphate ions, and an aqueous raffinate (21) containing calcium chloride and residual impurities; re-extracting the phosphate ions from the organic extract (17) with water (18), thus yielding an aqueous extract (19) of phosphoric acid, and an unloaded organic phase substantially free of phosphoric acid, reacting (107) the raffinate (21) containing calcium chloride with sulphuric acid (26) to cause precipitation of calcium ions in the raffinate as calcium sulphate dihydrate and to recover chloride ions in the raffinate in the form of hydrochloric acid (12), wherein the reaction of the raffinate (21) containing calcium chloride with sulphuric acid (26) involves intermittent agitation of the raffinate, filtering off (108) precipitated calcium sulphate dihydrate (27) from the previous step (107) and washing it with water, recycling (112) the recovered hydrochloric acid (12) to the step (101) of the leaching apatite.

This process for the recovery of rare earths contained in ionic clays implements the leaching of said clays according to a continuous loop: in which said leaching is initiated by contacting fresh ionic clay with an aqueous leaching solution S1 comprising a dissolved salt of M1 / zCl or M2 / zSO4, where M is a cation chosen from the group consisting of Na+, NH4+ and Mg2+; and z = 1 or 2, representing the number of charges of the cation M, generating on the one hand, a leachate or aqueous solution S2 comprising rare earth cations and actinium, and on the other hand, a leached or exhausted clay; then in which, said solution S2 is subjected to a phase of extraction of the valued rare earths, generating on the one hand, an organic solution S3 or a solid S3 comprising the valued rare earths, and on the other hand a raffinate R comprising the salt of M1 / zCl or of M2 / zSO4, actinium in cationic form, and the non-valued rare earths;The raffinate R is brought into contact with a quantity of fresh ionic clay, forming a new solution S2; said new solution S2 is then subjected to a new phase of extraction of the valuable rare earths, generating a new raffinate R; the leaching solution constituted by the raffinate R resulting from the successive phases of extraction of the valuable rare earths, continuously circulating in connection with new quantities of fresh ionic clay. Figure 1;

This invention provides a method for recovering valuable metals from waste ternary lithium battery cathode materials. The recovery method includes: (1) reducing and leaching the black powder of waste ternary lithium battery cathode materials to obtain a leaching slurry, and removing impurities from the leaching slurry to obtain a ternary leachate; (2) extracting the ternary leachate to remove calcium and copper to obtain an organic phase loaded with calcium and copper and a raffinate after calcium and copper extraction; (3) treating the raffinate after calcium and copper extraction with resin to remove fluoride and phosphorus to obtain a solution after fluoride and phosphorus removal; (4) co-extracting the solution after fluoride and phosphorus removal with nickel, cobalt, and manganese to obtain a mixed solution containing nickel, cobalt, and manganese and a lithium-containing solution. The recovery method provided by this invention has a high recovery rate of valuable metals, thorough separation of impurities, and yields a battery-grade mixed solution of nickel, cobalt, and manganese that can be directly used to prepare ternary precursors. It also achieves lithium recovery. The recovery method is simple, efficient, and has low environmental pollution.

The present application relates to a kind of low sulfur high performance fuel oil production device, it relates to fuel oil production technical field.Low sulfur modified residual oil, hydrogenation low sulfur raffinate are used as main raw material, auxiliary agent A, auxiliary agent B prepared by special oil device are matched, reaction conditions are accurately controlled through DCS system, low sulfur high performance marine fuel oil is prepared in low temperature mild environment;Device integrates vacuum deep pull and viscosity reduction cracking combined process, light fraction can be deep-processed into three kinds of base oil, etc.Additional value products, heavy fraction is reduced in viscosity by viscosity reduction cracking, and low-temperature fluidity is improved;Auxiliary agent B is prepared by dithiophosphoric acid, molybdenum trioxide, epoxy succinic acid polymer, 2,6-naphthalene dicarboxylic acid, anhydrous toluene, phosphorous acid;Fuel oil prepared by the present application, sulfur content is lower, environmental protection is better, low-temperature fluidity is improved, and combustion efficiency is better.

This invention provides a method for the synergistic resource utilization of zinc-aluminum alloy welding slag and hot-dip galvanizing waste hydrochloric acid. The synergistic resource utilization method includes the following steps: (1) mixing zinc-aluminum alloy welding slag and hot-dip galvanizing waste hydrochloric acid, and performing dissolution and neutralization treatment to obtain a first treatment liquid; (2) extracting the first treatment liquid to obtain an extract and a raffinate; (3) back-extracting the extract to obtain a mixture of zinc chloride and ammonium chloride; and then performing evaporation and crystallization treatment to obtain zinc ammonium chloride; and finally, aging the raffinate to obtain polyaluminum ferric chloride. The synergistic resource utilization method of this invention is simple to operate, has low processing costs, and realizes the synergistic treatment of industrial waste zinc-aluminum alloy welding slag and hot-dip galvanizing waste hydrochloric acid, which has good economic and environmental benefits and is suitable for large-scale promotion and application.

The application provides a method for preparing cobalt-doped ferromanganese subphosphate by using iron phosphate sewage treatment sludge, and comprises the following steps: adding acid liquor into the iron phosphate sewage treatment sludge, performing acid leaching reaction, performing solid-liquid separation, and obtaining filtrate A; adding an extraction agent into the filtrate A, and performing extraction to obtain an extracted organic phase and a raffinate; performing multistage impurity removal on the raffinate to obtain a cobalt-manganese-phosphorus-containing solution, supplementing an iron source and a phosphorus source, and using a hydrothermal synthesis method to obtain a cobalt-doped ferromanganese subphosphate crude product, which is washed, dried and calcined to obtain the cobalt-doped ferromanganese subphosphate. The method can comprehensively recycle and utilize P, Mn and Co elements in the iron phosphate sewage treatment sludge, and reduces the production cost of the cobalt-doped ferromanganese subphosphate.

Process and device for simulated moving bed extraction of lithium by adsorption, in which at least one column (Ci) is supplied with a feed (F) comprising lithium and a desorbent (D), and an extract (E) and a raffinate (R) are withdrawn from the column. The column comprises an adsorbent solid (Ai) and is configured to operate in a closed loop. The supply and withdrawal points of the column are shifted over time by a value corresponding to a predetermined quantity of adsorbent solid with a permutation period and determine a plurality of operating zones of the column, in particular the following main zones: a lithium desorption zone I; a desorption zone II of compounds other than lithium; and a lithium adsorption zone III. According to the invention, a portion of the extract is recycled to the feed.

The application belongs to the technical field of battery material recycling, and particularly discloses a battery black powder recycling method. The battery black powder recycling method provided by the application comprises the following steps: obtaining lithium-containing leaching liquor and leaching residue by pressurized acid leaching of battery black powder; performing acid leaching reaction on the leaching residue to obtain nickel-, cobalt- and manganese-containing leaching liquor; adding an oxidizing agent to the nickel-, cobalt- and manganese-containing leaching liquor, adjusting the pH by using alkali to remove iron and aluminum, and filtering to obtain a post-iron-and-aluminum-removal liquid; extracting Ca by using HBL120 extractant to obtain Co-, Ni- and Mn-containing raffinate; extracting Mn by using P204 extractant to obtain Mn-loaded organic phase and Co- and Ni-containing raffinate; extracting Co by using Cy272 extractant to obtain Co-loaded organic phase and Ni-containing raffinate; and removing F and P from the Ni-containing raffinate to obtain a nickel sulfate solution. The application has high lithium extraction rate and shortens the process flow of manganese recycling.

This invention discloses a method for extracting gallium from copper smelting dust. The method includes pretreatment, extraction, and back-extraction steps, specifically: adjusting the pH of a nickel-containing copper sulfate solution to 0.5-1.0 with a pH adjuster to obtain material a; extracting material a with a composite extractant to obtain an organic phase b and an aqueous phase c; back-extracting organic phase b with a sulfuric acid solution to obtain a gallium-containing solution d and a raffinate e; the composite extractant is composed of N235 extractant, 2-octanol, and sulfonated kerosene. This invention recovers gallium from copper smelting dust, efficiently enriching low-concentration gallium, improving recovery rate, supplementing traditional gallium extraction channels, extending the copper industry chain, increasing added value, harmlessly treating harmful impurities in the dust, reducing environmental costs, and strengthening my country's strategic gallium resource protection capabilities. Therefore, developing this recovery technology is a key measure to solve the problem of separating and enriching low-concentration gallium and to solidify industrial security.

This invention relates to the field of lithium extraction technology from lithium-containing organic wastewater, specifically to a method for preparing battery-grade lithium carbonate from lithium-containing organic wastewater. The method provided by this invention first recovers organic acids from the wastewater through esterification and hydrolysis reactions. Then, under pH 11-12 conditions, lithium is precipitated with trisodium phosphate to obtain crude lithium phosphate solid. The lithium is then enriched, dissolved in acid, and extracted to remove phosphoric acid. The raffinate is adjusted to pH 9-11 to remove impurities, yielding a lithium sulfate solution. After concentration using MVR (Medium-Volume Reduction), impurities are further removed under pH 10.5-11.5 and activated carbon adsorption conditions to obtain a pure lithium sulfate solution. The obtained pure lithium sulfate solution is mixed with a carbonate solution to obtain crude lithium carbonate. Finally, after washing, drying, crushing, and iron removal, battery-grade lithium carbonate is obtained.

A method for recovery of rare earth elements from apatite mineral comprises dissolving (S10) of apatite mineral of magmatic origin in an acid comprising hydrochloric acid. The dissolving results in a first liquid solution comprising phosphate, calcium and chloride ions, rare earth elements, arsenic and iron. The arsenic and any ferric iron are removed. The first liquid solution is treated (S20) into a second liquid solution by extracting (S22) of a major part of the phosphate ions with an organic solvent. The treating of the first liquid solution into the second liquid solution further comprises partially neutralizing (S75) a raffinate resulting from the extracting of a major part of the phosphate to a pH > 1.5, causing precipitation of phosphates of rare earth elements, and filtering (S76) the precipitated phosphates of rare earth elements from the raffinate.

This application provides a method for selectively separating vanadium and chromium from chromium-vanadium slag leachate, relating to the field of solid waste recycling. The method includes: diluting a hydrophobic eutectic solvent with a diluent to obtain an extractant; mixing the extractant with the chromium-vanadium slag leachate, performing shake extraction, allowing the mixture to stand and separate phases to obtain a vanadium-loaded organic phase and a raffinate; washing and back-extracting the organic phase to obtain a vanadium-poor organic phase and a vanadium-rich back-extract; then subjecting the vanadium-rich back-extract to vanadium precipitation treatment and a first calcination to obtain vanadium pentoxide; the hydrophobic eutectic solvent is obtained by heating and stirring a mixture of a hydrogen bond donor and a hydrogen bond acceptor, wherein the hydrogen bond acceptor is composed of a neutral phosphorus-containing organic compound and a hydrophobic quaternary ammonium salt. This method can achieve selective separation of vanadium and chromium, effectively solving the problem of vanadium and chromium separation from chromium-vanadium slag leachate, and has good application prospects in the field of selective separation of vanadium and chromium to prepare high-purity vanadium and chromium products.

This invention relates to a method for preparing crude cobalt intermediate from cobalt-containing copper raffinate. The method includes the following steps: (1) adding a first precipitant to the cobalt-containing copper raffinate for neutralization and impurity removal, and obtaining a first precipitated liquid and a first precipitated residue after solid-liquid separation; (2) adding a second precipitant to the first precipitated liquid for cobalt precipitation, and obtaining a cobalt-precipitated liquid and a mixed precipitate after solid-liquid separation; (3) adding a leaching agent to the mixed precipitate for leaching, and obtaining a leachate and a leaching residue after solid-liquid separation; (4) adding a reducing agent to the leachate for reductive distillation, and obtaining crude cobalt intermediate and a reductive distillate after solid-liquid separation. This invention achieves efficient separation of cobalt from impurities such as copper, significantly improves the purity of crude cobalt intermediate and cobalt recovery rate, has a simple process flow, low reagent consumption, and is suitable for industrial production.

This application discloses a high-concentration thallium solvent extraction method for the lithium salt extraction industry, belonging to the field of hydrometallurgical technology. The method provided by this application includes the following steps: Step S1: Adding a pH adjuster to the thallium waste liquid to adjust the pH, then adding an oxidant, and stirring to react and obtain a mixed solution; the pH adjuster is HCl; Step S2: Adding an extractant and a diluent to the mixed solution, stirring to extract and separate, obtaining a thallium-containing organic phase and a first raffinate; the extractant includes N503 extractant and tributyl phosphate; Step S3: Washing the thallium-containing organic phase with hydrochloric acid solution, then adding ammonium acetate solution for back-extraction and separation, obtaining a back-extraction solution and a second raffinate. The method of this application has good selectivity, high extraction rate, low environmental pollution, low cost, and the extractant can be reused.

A simulated moving-bed lithium adsorption process and apparatus in which a column (Ci) comprising a solid adsorbent is fed with a feed (F) comprising lithium and a desorbent (D) and is withdrawn of a raffinate (R) and an extract (E2), the column being divided into several predetermined quantities of solid adsorbent according to a permutation period defining the following zones: a zone I between the injection of the desorbent and the withdrawal of an eluate (E1) and the extract, a zone II between the withdrawal of the raffinate and the injection of the desorbent, and a zone III between the injection of the feed and the withdrawal of the raffinate, in which each permutation period comprises two steps: a step A of eluate withdrawal from zone I and a step B of extract withdrawal from zone I. Figure 3 to be published

The present application relates to the technical field of separation and purification, in particular to a method for recovering 2,4,6-trimethylphenol from 2,6-dimethylphenol residue, comprising: cooling the 2,6-dimethylphenol residue to 15±1 DEG C, and keeping the temperature for 10-40 min, then blowing out the liquid material by compressed gas; heating and melting the crystallized solid material, keeping the temperature for 0-40 min, then cooling to 30±1 DEG C, keeping the temperature for 10-40 min, then blowing out the liquid material by compressed gas; heating and melting the crystallized solid material, keeping the temperature for 0-40 min, then cooling to 40-45 DEG C, keeping the temperature for 10-40 min, then blowing out the liquid material by compressed gas; heating and melting the crystallized solid material, and discharging to obtain 2,4,6-trimethylphenol. The present application significantly improves the recovery rate and purity of 2,4,6-trimethylphenol by multiple melting and crystallization in stages and blowing out the liquid material by compressed gas.

This invention provides a method for recovering nickel from high-temperature alloys. The method includes the following steps: electrochemically dissolving the high-temperature alloy to obtain a nickel-containing electrolyte and anode mud; adjusting the pH of the nickel-containing electrolyte until impurity metal ions form a precipitate, separating the precipitate to obtain a purified solution; mixing the purified solution, a chloride-containing solution, and an extractant for extraction to separate a cobalt-supported organic phase and a nickel-containing raffinate; adjusting the pH of the nickel-containing raffinate until nickel ions are converted into nickel precipitate, and then reducing the nickel precipitate with hydrogen plasma to obtain metallic nickel powder. The recovery process provided by this invention achieves high purity nickel recovery from high-temperature alloys, significantly shortens the single-batch operation cycle, improves recovery efficiency, and can meet the needs of large-scale, high-load continuous production.

A simulated moving-bed lithium adsorption extraction method and apparatus using / comprising an extraction column (7) fed with a charge (6) comprising lithium and a desorbent (9) to withdraw an extract (10) and a raffinate (8), the column comprising a solid adsorbent (Ai) and being configured to operate in a closed loop, the column's feed and withdrawal points being offset over time by a value corresponding to a predetermined quantity of solid adsorbent with a permutation period and determining a plurality of column operating zones, in which the extract is sent directly to an evaporation section (17) adapted to separate water (18) and produce a concentrate (19). Figure 2 to be published

This invention belongs to the fields of chemical metallurgy and environmental protection technology, specifically relating to a method for recovering ferrophosphate and simultaneously removing thorium from rare earth waste residue, and a ferrophosphate product. The method targets rare earth waste residue containing insoluble ferrophosphate. After grinding pretreatment, it undergoes enhanced acid hydrolysis at 75-85°C using 70-80% sulfuric acid. The high concentration of protons disrupts pyrophosphate bonds, achieving efficient leaching of phosphorus and iron while inhibiting the dissolution of calcium impurities. The strongly acidic filtrate after solid-liquid separation is subjected to multi-stage extraction using a primary amine extractant (N1923) to selectively remove radioactive thorium. The raffinate is then pH-controlled to induce the synthesis of battery-grade ferrophosphate. This invention achieves a phosphorus recovery rate >92% and a thorium removal rate >99.5%, not only solving the environmental pollution problem caused by rare earth waste residue storage but also preparing a high-value-added lithium battery cathode material precursor.

Methods for recovering a metal value from a metal-bearing material are provided. The method comprises agglomerating the metal-bearing material with an agglomeration solution comprising a raffinate, an oxidant, and citric acid or salts thereof to form an agglomerated metal-bearing material; leaching the agglomerated metal-bearing material with a leaching solution comprising the raffinate and the citric acid or salts thereof to produce a pregnant leaching solution and a leached material; re-oxidizing the leached material with a curing solution comprising the raffinate and the oxidant; and recovering the metal value from the pregnant leach solution to produce the raffinate.

This application provides a bioleaching method for low-grade copper ore, comprising the following steps: crushing copper-bearing ore and pyrite separately, screening to obtain copper ore powder and iron ore powder, mixing the copper ore powder and iron ore powder and piling them in a heap leaching column, and burying vertical pipes in the heap to obtain a heap; spraying the heap with acid, then inoculating with leaching bacteria solution to carry out the heap leaching process; the leaching process uses raffinate for circulating leaching. The method of this application uses bioleaching to treat low-grade copper ore, which has the advantages of high leaching rate, low pollution, water conservation, and ease of operation. It overcomes the disadvantages of traditional flotation methods for separating low-grade copper ore, which are not only difficult to process but also have extremely low flotation yields, making it difficult to obtain high-grade copper concentrate.

The invention relates to a method and device for extracting lithium by adsorption in a simulated moving bed in which a column (Ci) comprising an adsorbent solid is fed with a feedstock (F) comprising lithium and a desorbent (D), and a raffinate (R) and an extract (E2) are drawn off from the column, the column being divided into a plurality of predetermined quantities of adsorbent solid according to a switching period defining the following zones: a zone I between the injection of the desorbent and the drawing off of an eluate (E1) and the extract; a zone II between the drawing off of the raffinate and the injection of the desorbent; and a zone III between the injection of the feedstock and the drawing off of the raffinate, wherein each switching period comprises two steps: a step A of drawing off eluate from zone I and a step B of drawing off extract from zone I.

The present application relates to the technical field of aromatic hydrocarbon extraction, and discloses a method and device for aromatic hydrocarbon extraction. The method comprises the following steps: (1) contacting reforming gasoline with an extraction solvent to perform extraction, to obtain first rich agent and raffinate; (2) separating the first rich agent to obtain second rich agent and reflux aromatic hydrocarbon; (3) returning the reflux aromatic hydrocarbon to step (1); (4) contacting the second rich agent with stripping water vapor to perform stripping, to obtain lean solvent and aromatic hydrocarbon; (5) dividing the lean solvent into at least A part and B part, returning the A part to step (1) as extraction solvent, and returning the B part to step (2). The method for aromatic hydrocarbon extraction provided by the present application introduces lean solvent into the top of the stripping column, reduces the content of aromatic hydrocarbon, especially toluene, in the gas phase at the top of the stripping column, moves most of the toluene to the stripping column to be distilled out, thereby reducing the extraction amount of the reflux aromatic hydrocarbon, and further reducing the aromatic hydrocarbon reflux ratio and improving the extraction capacity of the extraction column.

The present invention relates to a process for purifying a plastic feedstock to obtain a stream of purified polyolefins, comprising: a) a dissolution step by contacting the plastic feedstock with a dissolving solvent; then b) a size exclusion extraction step, employing beds of a size exclusion solid in series and fed with the polymer solution from a) at an injection point (F) and with an eluent at an injection point (S) and employing a withdrawal of an extract at a withdrawal point (E) and a withdrawal of a raffinate comprising a purified polymer solution at a withdrawal point (R), the injection and withdrawal points being distinct and offset over time by one bed according to a determined frequency; then c) a polymer-solvent separation step, to obtain a stream of purified polyolefins.The invention also relates to a device for carrying out step b) and a device for carrying out the purification process. Figure 1 to be published.

This application discloses a method and apparatus for producing bio-based pentanediamine. The method includes: using pentanediamine fermentation broth and / or its treated broth as raw materials, decarbonizing the raw materials to obtain a decarbonized liquid, then subjecting the decarbonized liquid to alkaline hydrolysis to obtain an alkaline hydrolysate; extracting the alkaline hydrolysate using an extractant and an auxiliary agent, collecting the oil phase to obtain an extract; removing light components from the extract, then separating pentanediamine and the extractant by distillation to obtain high-purity pentanediamine; and passing the raffinate through a crystallization evaporation system to obtain crystalline salt and organic fertilizer. This application enables the continuous industrial production of pentanediamine. Extraction with a multi-component extractant and auxiliary agent transfers pentanediamine to the oil phase, and controls emulsification and entrainment in the oil phase, preventing salt from entering the oil phase and avoiding salt precipitation during subsequent refining processes that could cause equipment and pipeline blockage. High-purity pentanediamine is obtained by distillation of the oil phase, avoiding the enormous energy consumption of traditional water concentration methods.

The disclosure relates to a continuous process for obtaining phosphoric acid and calcium sulphate dihydrate from apatite, and sulphuric acid using hydrochloric acid as an intermediate attacking agent, comprising the steps: Leaching (101) apatite (11) with an aqueous solution of hydrochloric acid (12,13) to solubilize phosphorus compounds contained in the apatite, thereby obtaining a solution (15) containing phosphate (H3PO4) and calcium chloride (CaCl2); extracting (103) said solution (15) with organic solvent (16), yielding an organic extract (17) loaded with phosphate ions, and an aqueous raffinate (21) containing calcium chloride and residual impurities; re-extracting the phosphate ions from the organic extract (17) with water (18), thus yielding an aqueous extract (19) of phosphoric acid, and an unloaded organic phase substantially free of phosphoric acid, reacting (107) the raffinate (21) containing calcium chloride with sulphuric acid (26) to cause precipitation of calcium ions in the raffinate as calcium sulphate dihydrate and to recover chloride ions in the raffinate in the form of hydrochloric acid (12), filtering off (108) precipitated calcium sulphate dihydrate (27) from the previous step (107) and washing it with water, dividing (113) the remaining hydrochloric acid (12) aqueous solution into a primary stream (12a) and a secondary stream (12b); and recycling (112) the primary stream (12a) of the aqueous solution of hydrochloric acid (12) to the step (101) of the leaching apatite, and at least partially removing the secondary stream (12b) from the process.

This application provides a method for catalytic oxidation-stepwise precipitation of lateritic nickel ore leaching solution, relating to the field of hydrometallurgy. The method includes: adding a catalytic oxidant and a first neutralizing agent to the lateritic nickel ore leaching solution to obtain a first filtrate and iron slag; adding a catalytic oxidant, a second neutralizing agent, and a first agglomerating agent to the first filtrate to obtain a second filtrate and a second precipitate; adding a third neutralizing agent and a first reducing agent to the second filtrate to obtain a nickel-cobalt precipitate and a third filtrate; adding a fourth neutralizing agent and a second reducing agent to the third filtrate to obtain a fourth precipitate and a fourth filtrate; mixing the second precipitate with the third reducing agent and performing reduction leaching; adding a second agglomerating agent and a fifth neutralizing agent to obtain a silicon-aluminum precipitate and a manganese-scandium filtrate; extracting the manganese-scandium filtrate, with manganese entering the raffinate; adding a catalytic oxidant and a sixth neutralizing agent to the raffinate to obtain manganese oxide. This application enables stepwise element recovery, offering advantages such as recovering a wide variety of elements and minimizing resource waste.

This invention relates to the field of special fuel technology and discloses a method for preparing special fuels from coal tar, comprising: (1) performing a first fractionation on the raw coal tar to obtain a distillate oil with a distillation range of 180-420℃; (2) extracting the distillate oil to obtain an extract and a raffinate, and then performing adsorption separation on the raffinate to obtain a purified oil product; (3) optionally hydrorefining the purified oil product; (4) performing a second fractionation on the purified oil product and / or the hydrorefined product to cut it into No. 1 distillate oil, No. 2 distillate oil, and No. 3 distillate oil; (5) alkylating the No. 1 distillate oil to obtain No. 1 special oil; hydrosaturating the No. 2 distillate oil to obtain No. 2 special oil; and cracking cycloisomerizing the No. 3 distillate oil to obtain No. 3 special oil; and (6) then refining and blending. This method can flexibly prepare special fuels with different properties, and the fuel density and calorific value range are large.