118 results about "CAUSTIC ALKALIS" patented technology

The present invention discloses a method and apparatus for recovering iron from red mud. The specific process is as follows: red mud slurry in the red mud pipeline of the alumina workshop is mineralized, the mineralized red mud slurry is fed into an electrolysis system for electrolysis, the caustic soda concentration in the electrolyte is controlled to be 5-25 mol / L, the electrolysis voltage is between 1.3V and 1.6V, and the red mud slurry temperature in the electrolysis system is maintained between 110-120°C. The electrolysis is stopped after 2-8 hours, and the iron on the cathode of the electrolysis system is stripped and disposed of to obtain a high-purity iron product. Using the present invention, the iron product recovered from red mud is higher in purity, with lower energy consumption and better environmental protection.

The invention discloses a method for preparing phenol by utilizing a biomass raw material, which comprises the following steps: 1) crushing biomass, adding the crushed biomass into a caustic alkali solution to carry out hemicellulose removal treatment, and carrying out solid-liquid separation to take a solid substance, so as to obtain hemicellulose-removed biomass; 2) adding the hemicellulose-removed biomass into an ethylene glycol-ferric chloride eutectic solvent for lignin extraction, then adding an acetone-water mixed solution, then carrying out solid-liquid separation, taking a liquid substance, adding water to precipitate the lignin, then carrying out solid-liquid separation, and taking a solid substance to obtain the lignin; and 3) pyrolyzing the lignin in a protective atmosphere to obtain lignin oil containing phenol. The method for preparing phenol from biomass raw materials has the advantages of simple operation, high phenol yield, high product purity, low energy consumption, safety, environmental protection and the like, and is suitable for large-scale industrial application.

The invention belongs to the technical field of mineral flotation, and particularly discloses a xanthate collecting agent and a preparation method and application thereof, and the xanthate collecting agent is obtained by taking ether alcohol, carbon disulfide and caustic alkali as raw materials to react; the xanthate collecting agent is selected from at least one of formulas I-VI. The xanthate collecting agent has the advantages of being free of peculiar smell, easy to degrade, high in yield, high in purity, efficient in mineral flotation and the like, the working environment of the xanthate collecting agent in the production and using process can be effectively improved, operation is easy and convenient, cost is low, and industrial production is easy to achieve.

The invention relates to the technical field of red mud waste recycling, in particular to an improved red mud recycling method. The method comprises the following steps: carrying out dissolution reaction on red mud, alkali liquor and degassed carbide slag to obtain a dissolved substance; carrying out solid-liquid separation on the dissolved substance to respectively obtain a liquid product and solid waste; the liquid product is used for alumina production circulating mother liquor; the solid waste comprises molten garnet. According to the method, the mass concentration and the weight of the caustic alkali in the alkali liquor and the addition amount of the degassed carbide slag are adjusted according to different iron oxide contents in the red mud, so that sodium resources and aluminum resources in the red mud can be effectively recovered on the premise of fully considering the iron oxide contents in the red mud, and the recovery rates of the sodium resources and the aluminum resources in the red mud are improved; meanwhile, the degassed carbide slag is consumed as much as possible, so that the content of sodium oxide in the final solid waste can be reduced to be within 1%, and a foundation is laid for comprehensive utilization of the solid waste.

The invention belongs to the technical field of preparation of adsorption materials, and relates to a 13X molecular sieve adsorbent for removing CO2 as well as a preparation method and application of the 13X molecular sieve adsorbent. The preparation method comprises the following steps: firstly, soaking clay powder in an acid solution, and carrying out filter pressing to obtain a clay filter cake; then, mixing the high-silica-alumina-ratio 13X molecular sieve, the clay filter cake and a pore-forming agent, granulating and forming, and drying and roasting to obtain the spherical high-silica-alumina-ratio 13X molecular sieve adsorbent with the particle size of 1.6-2.4 mm, and finally, treating the 13X molecular sieve adsorbent with the high silica-alumina ratio in a caustic alkali solution, washing, drying and roasting to obtain the efficient 13X molecular sieve adsorbent for removing CO2. According to the method, one-step aluminizing-directional crystal transformation is realized, and the prepared 13X molecular sieve adsorbent has higher CO2 adsorption capacity and is suitable for efficient removal of trace CO2 in air separation.

The present invention relates to a process for the recovery of waste materials by producing soda ash, sodium hydroxide and hydrogen via converting the liquid and solid wastes, which are generated as a result of production from the Trona ore using solution mining and underground production methods, into a solution; and a process that will enable production in brine production areas that are currently not suitable for production.

The present disclosure relates to a biodegradable porous bonded-grain monolithic CO2 scrubber for respiration devices. The scrubber comprises a monolithic body of bonded grains, including calcium hydroxide, sodium hydroxide, lithium hydroxide, and potassium hydroxide, to act as CO2 absorbents. The body features enclosed gas passages facilitating gas flow and CO2 absorption. The grains are bonded via adhesion, powder polymer, or heat sintering, and the structure includes hydrophobic additives to reduce caustic solution formation. The scrubber can be manufactured through extrusion or additive manufacturing, with various passage shapes and sizes. The monolithic body may include biodegradable polymers for environmentally sound disposal.

A method for treating a blowdown stream from a sodium carbonate, sesquicarbonate, wegsheiderite, or bicarbonate crystallizer, said blowdown stream comprising sodium carbonate and / or sodium bicarbonate and at least 1 wt% sodium chloride and / or sodium sulfate, the method comprising: - causticizing at least 50 mol% of the sodium from the sodium carbonate and / or sodium bicarbonate in a caustic solution and in a calcium carbonate sludge with lime and water, - separating the calcium carbonate sludge from the caustic solution; - concentrating the caustic solution by removing some of the water to obtain a concentrated caustic solution containing at least 25% NaOH and a crystallized solid containing sodium carbonate and sodium chloride and / or sulfate; - separating the crystallized solid from the concentrated caustic solution, said crystallized solid to be disposed of or subsequently recovered;- Recycle part of the concentrated caustic solution to the sodium carbonate, sesquicarbonate, wegsheiderite or bicarbonate crystallizer.;

The invention relates to the technical field of aluminum hydroxide preparation, in particular to a method for preparing superfine aluminum hydroxide particles and the superfine aluminum hydroxide particles. The method comprises the following steps: mixing a supersaturated sodium bicarbonate solution and a first Bayer process sodium aluminate solution to obtain a seed slurry containing amorphous aluminum hydroxide; wherein the solid content of the amorphous aluminum hydroxide is greater than 30g / L; and performing decomposition reaction on the second Bayer process sodium aluminate solution and the seed slurry containing the amorphous aluminum hydroxide to obtain decomposed slurry containing the superfine aluminum hydroxide particles. According to the method, the morphological characteristics of an aluminum hydroxide product generated by decomposing a sodium aluminate solution are accurately regulated and controlled on the basis of the characteristics of a large number of disordered structures of amorphous aluminum hydroxide, so that the median particle size of aluminum hydroxide particles is 0.3 mu m or less, the specific surface area is up to 15 m < 2 > / g-30 m < 2 > / g, the oil absorption is 35 mL / 100 g-45 mL / 100 g, and the weight content of caustic alkali is 0.2% or less.

The invention discloses a low-fluorine MXene material as well as a preparation method and application thereof. The preparation method of the low-fluorine MXene material comprises the following steps: mixing fluorine-containing MXene, caustic alkali, strontium salt, polyol and water for reaction, then carrying out product separation, and washing the product with hydrochloric acid to obtain the low-fluorine MXene material. The preparation method of the low-fluorine MXene material has the advantages of being good in fluorine removal effect, simple to operate, wide in reagent source, low in price, mild in reaction condition, short in treatment time, low in cost, safe in process and the like, the low-fluorine MXene material with excellent performance can be prepared, and the preparation method is suitable for large-scale industrial application.

The invention relates to a process for producing scandium oxide by comprehensively recovering bauxite. According to the method, scandium compounds in the red mud are activated through bubbling treatment, the pH value of a liquid phase is smaller than or equal to 10.5, after multi-stage filtration, insoluble residues are leached through a sodium carbonate-sodium bicarbonate solution, and a scandium-containing sodium carbonate-sodium bicarbonate solution is obtained; after filtering the obtained solution, mixing a scandium-containing alkaline aluminate solution with a scandium-containing sodium carbonate-sodium bicarbonate solution to prepare a scandium-containing hydrolysis concentrate; carrying out two-stage sulfuric acid leaching on the filtered scandium-containing hydrolysis concentrate; the scandium-containing sulfuric acid solutions obtained after two-stage leaching are mixed, alkali is added to adjust the pH to 4.5-5.5, and scandium sulfate without impurity elements is precipitated; then treating with caustic alkali until the pH is not more than 5.6, and carrying out selective precipitation of scandium; treating scandium sulfate with a sulfuric acid solution to obtain basic scandium sulfate; treating the obtained basic scandium sulfate with oxalic acid to convert the basic scandium sulfate into scandium oxalate; filtering the obtained scandium oxalate precipitate; and calcining scandium oxalate to remove carbon and obtain scandium oxide, wherein the content of Sc2O3 in the calcined product is at least 99.0 mass percent.

The invention provides a method for recovering a weighting agent in shale gas drilling cuttings. The method mainly comprises the following steps: (1) adding a proper amount of acidic solution into the deoiled drilling cuttings to remove impurity metal ions, filtering, washing and drying; (2) mixing the drilling cuttings subjected to impurity removal with caustic alkali; (3) dissolving and enriching silicon and aluminum components in the mixed material under a high-temperature and high-pressure hydrothermal condition; and (4) filtering to obtain a filtrate which is a water glass crude product, and washing and drying filter residues to obtain the barite weighting agent. In order to solve the problems that shale gas drilling cuttings are large in yield, high in environmental harm and difficult in barite weighting agent recovery, efficient recovery of barite in the drilling cuttings can be achieved by conducting alkali dissolution on silicon and aluminum components in the drilling cuttings. The method for recovering barite has the advantages of simple process, low cost, low energy consumption and high recovery rate, can be applied to industrial production, and also has certain recovery value as the byproduct is the crude sodium silicate product.

A process, a system, and an apparatus are provided for converting a lower alkane to an alkene. Oxygen and the lower alkane are provided to an ODH reactor to convert at least a portion of the lower alkane to an alkene. An ODH stream comprising the alkene, an oxygenate, steam, and a carbon-based oxide is produced. The bulk of the oxygenate is removed from the ODH outlet stream by non-dilutive cooling, with residual oxygenate being removed using dilutive quenching with a carbonate. Subsequently, separation of the carbon-based oxide from the alkene is achieved using a caustic tower, which also produces spent caustic in the form of a carbonate, which is then used as the carbonate for dilutive quenching. Dilutive quenching using a carbonate allows conversion of the oxygenate to an acetate, which can then be used to simplify separation of the oxygenate from water.

The invention discloses a recovery method of a catalyst containing platinum, silver, chromium, vanadium, molybdenum and aluminum, which comprises the following steps: uniformly mixing a waste catalyst, caustic alkali and iron powder, reacting at high temperature, cooling to obtain a melt, dissolving the melt, and filtering to obtain a first filter residue and a first filtrate; dissolving the first filter residue with nitric acid, and filtering to obtain platinum-containing waste filter residue and second filtrate; adding a sodium chloride solution into the second filtrate, and filtering to obtain silver chloride filter residues and third filtrate which contains chromic nitrate; adding a barium chloride solution into the third filtrate, reacting at room temperature, and filtering to obtain barium chromate solid filter residues and fourth filtrate; adjusting the pH value of the first filtrate to 7-8 by using an acid, reacting at room temperature, and filtering to obtain activated aluminum oxide filter residues and a fifth filtrate; adding ammonium chloride into the fifth filtrate, reacting at room temperature, and filtering to obtain ammonium vanadate filter residues and sixth filtrate; and adjusting the pH value of the sixth filtrate to be less than 1 by using sulfuric acid, reacting at room temperature, and filtering to obtain molybdic acid filter residues and a seventh filtrate.

The invention discloses a lime slaking slag caustic alkali recovery-thermoelectric flue gas desulfurization method which comprises the following steps: S10, preparing lime milk for alumina production by using a lime slaking machine, conveying the produced lime slaking slag to a slag washing machine through a slag extracting machine and a lime slag belt for washing, and overflowing and recovering the produced caustic alkali liquid for preparing the lime milk; s20, the washed lime slaking slag is smashed, and lime slaking slag powder is obtained; s30, blending the lime slaked slag powder with fire coal according to a certain proportion to form a mixed coal material, and feeding the mixed coal material into a thermoelectric coal-fired boiler for blending combustion for primary flue gas desulfurization; and S40, performing high-temperature dust removal on the flue gas subjected to primary flue gas desulfurization, and performing secondary flue gas desulfurization by adopting a lime powder-gypsum wet method. According to the method, the lime slaking slag caustic alkali can be effectively recovered and reutilized in thermoelectric flue gas desulfurization, the consumption of the caustic alkali of an aluminum oxide production system is reduced, and the limestone powder flue gas desulfurization cost of a thermoelectric coal-fired boiler is reduced.

Processes for producing a precipitated aluminum trihydrate (ATH) product from scrap or waste aluminum metal include the steps of contacting the aluminum metal with an activating composition containing gallium and / or indium to form an activated aluminum composition, reacting the activated aluminum composition with water and an ionic salt, a hydroxide, and / or an acid to form hydrogen gas and a first reaction mixture comprising solid ATH and a first solid fraction, isolating the solid ATH and the first solid fraction from the first reaction mixture, contacting the solid ATH and the first solid fraction with an aqueous caustic solution to form a second reaction mixture containing dissolved sodium aluminate, removing a second solid fraction from the second reaction mixture to form a liquor solution, seeding the liquor solution with a seed material to precipitate ATH and form a suspension, isolating precipitated ATH from the suspension and washing the precipitated ATH to form an intermediate ATH product, optionally milling the intermediate ATH product, and drying the intermediate ATH product to form the precipitated ATH product. Concurrently with the production of ATH is the production of molecular hydrogen and significant amounts of heat / energy.

A method of preparing a calcined hydrogenolysis / hydrogenation catalyst includes mixing a copper-containing material, manganese-containing material, sodium aluminate, and water to obtain an aqueous slurry; contacting the aqueous slurry with a caustic material to form a precipitate in a caustic aqueous slurry; removing the precipitate from the caustic aqueous slurry; and removing residual water from the precipitate to form a dried precipitate; calcining the dried precipitate to form the calcined hydrogenolysis / hydrogenation catalyst exhibiting a Brunauer-Emmett-Teller (“BET”) surface area of about 5 m2 / g to about 75 m2 / g. The calcined hydrogenolysis / hydrogenation catalyst may include a spinel structure crystallite size of about 15 nm or less. The calcined hydrogenolysis / hydrogenation catalyst may include a tenorite crystallite size of about 20 nm to 30 nm.

The invention discloses n-heptanoic acid prepared by oxidizing alcohol and a preparation method of the n-heptanoic acid, sec-octanol is taken as a raw material, a copper oxide-zinc oxide supported catalyst is added into a caustic alkali aqueous solution, reaction is carried out under the conditions that the temperature is 160-240 DEG C and the pressure is 1.0-2 MPa to obtain n-heptanoate, and then the n-heptanoic acid is obtained through acidification. The catalyst is added to promote the dehydrogenation reaction of the octanol and accelerate the reaction rate, so that the problem that the reaction is slow when the reaction temperature is lower than 320 DEG C is solved, by controlling the addition amount of water and the reaction pressure, generation of a 2-methyl-2-octene byproduct caused by dehydration of a system can be prevented, and by adding the defoaming agent, the yield of the 2-methyl-2-octene is increased. The problem of mass transfer difficulty caused by a large amount of foam in the later reaction stage is solved. According to the method disclosed by the invention, the yield of the n-heptanoic acid is more than 70% at 160-240 DEG C, and the method does not need to depend on a large amount of potassium hydroxide and has remarkable industrial advantages.

The invention relates to the technical field of tunnel type washing machines, and discloses a tunnel type washing machine capable of efficiently cleaning a cabin, the tunnel type washing machine comprises the cabin, a sliding groove is formed in the inner top surface of the cabin, a linear driving assembly is installed in the sliding groove, a cleaning assembly used for cleaning the inner side wall of the cabin is fixedly installed at the moving end of the linear driving assembly, and the cleaning assembly comprises a moving ring, an inserting ring and a rotating cylinder; a brush is installed on the side wall of the rotary drum, a plurality of water spraying holes are formed in the brush, a scraper is elastically installed on the side wall of the outer side of the rotary drum, and through cooperation of the linear driving assembly and the rotary driving assembly, the cleaning assembly achieves linear and rotary composite motion, and a spiral cleaning path is formed; a three-stage cleaning system is constructed by combining inclined scraping of the brush, synchronous flushing of the water spraying holes and stubborn stain stripping of the elastic scraper, dirt, stains and biological membranes on the inner wall of the cabin can be more comprehensively and deeply removed through the multi-dimensional cleaning mode, and the requirements for chemical agents such as high-concentration caustic alkali and a chlorine bleaching agent are reduced.

The invention belongs to the technical field of flotation collectors, and relates to a high-purity xanthate flotation collector and a preparation method and application thereof. The preparation method comprises the following steps: by taking excessive alcohol as a reaction raw material and a solvent, adding methylbenzene and dichloromethane as auxiliary solvents, then adding caustic alkali and carbon disulfide, and fully stirring and reacting in a reaction kettle; part of the solvent is removed through first ternary azeotropy, and then generated moisture is removed through second ternary azeotropy; and the high-purity xanthate flotation collecting agent is prepared and obtained through ultrasonic induced crystallization. The method provided by the invention has the technical advantages of high safety, mild reaction, few side reactions, convenience in operation and the like, and the xanthogenate prepared by the method has the characteristics of high purity and small taste, and has a remarkable industrialization prospect.

This invention relates to the field of plate heat exchanger technology, specifically to a fully welded plate heat exchanger for caustic alkali evaporation, comprising several heat exchange modules that are detachably connected in sequence. Each heat exchange module includes a set of symmetrically arranged fixed plates and heat exchange plates arranged side by side between the fixed plates. Each set of heat exchange plates is welded in sequence to form a plate bundle, and both ends of the plate bundle are fixedly connected to the opposite fixed plates. This invention can reduce maintenance requirements and personnel barriers, enabling the replacement of faulty heat exchange modules on the production site, quickly restoring production, reducing downtime losses, and reducing the possibility of heat exchange module leakage and damage, thus reducing the frequency of heat exchange plate replacement.

A method for treating a purge stream derived from a sodium carbonate, sesquicarbonate, wegsheiderite, or bicarbonate crystallizer, said purge stream comprising sodium carbonate and / or sodium bicarbonate and at least 1 % by weight of sodium chloride and / or sodium sulfate, the method comprising : - causticizing at least 50 mol. % of the sodium from sodium carbonate and / or sodium bicarbonate into a caustic solution and into a calcium carbonate mud with lime and water, - separating the calcium carbonate mud from the caustic solution; - concentrating the caustic solution by removing part of the water to obtain a concentrated caustic solution comprising at least 25 % NaOH, and a crystallized solid comprising sodium carbonate and sodium chloride and / or sulfate, - separating the crystallized solid from the concentrated caustic solution, said crystallized solid to be disposed of or to be further valorized, - recycling part of the concentrated caustic solution to the sodium carbonate, sesquicarbonate, wegsheiderite, or bicarbonate crystallizer.

The present application relates to a kind of fly ash geopolymer-based photovoltaic pile and its preparation method and application, belong to salt alkali photovoltaic pile and solid waste resource utilization technical field.The preparation method includes the following steps: S1: using coal series kaolin to prepare metakaolin;S2: after mixing with red mud and caustic soda, high-temperature calcination is carried out, then the obtained calcination product is ground and sieved, to obtain alkali fusion material;S3: the metakaolin, the alkali fusion material and fly ash are mixed, then water is injected into mould and is shaped treatment, and photovoltaic pile is obtained after demoulding and curing.The production process of photovoltaic pile in the present application is low carbon and environmentally friendly, realizes the resource utilization of red mud and fly ash;In addition, photovoltaic pile has dense three-dimensional network structure, strong alkali resistance, salt and erosion resistance, and by adjusting liquid-solid ratio and raw material ratio, the setting time can be obviously shortened, which is beneficial to the application of photovoltaic pile in offshore and saline-alkali soil photovoltaic power generation, wind power foundation structure.

Provided are: an ion exchange membrane which has small variation in current efficiency, and with which it is possible to produce an aqueous alkali hydroxide solution that has excellent caustic quality; an alkali chloride electrolysis apparatus which comprises the ion exchange membrane; and a method for producing an alkali hydroxide.　The ion exchange membrane comprises a layer (S) that contains a fluorine-containing polymer having a sulfonic acid-type functional group and a layer (C) that contains a fluorine-containing polymer having a carboxylic acid-type functional group, wherein: a woven fabric is disposed in the layer S; the woven fabric is configured from yarns A that extend in one direction and yarns B that extend in a direction substantially orthogonal to the yarns A; and the amount of displacement of the ion exchange membrane is 10-20 mm when a pulling operation is performed for 10 minutes, the pulling operation repeatedly performing an operation 1 for pulling the ion exchange membrane for 1 second at a pulling load of 10 N and an operation 2 for pulling the ion exchange membrane for 0.1 second at a pulling load of 0.1 N in a direction that is at an angle of 45 degrees to the direction in which the yarns A extend in the plane of the ion exchange membrane.

The utility model belongs to the technical field of aluminum oxide processing, and relates to an aluminum oxide continuous decomposing and lifting system which comprises at least three decomposing tanks, and stirring devices are arranged in the decomposing tanks; the decomposition tank comprises a first decomposition tank, a second decomposition tank and a third decomposition tank, material lifting pipes are arranged in the first decomposition tank and the second decomposition tank, the material lifting pipes are connected with the second decomposition tank through a first decomposition tank discharging chute, and the second decomposition tank is connected with the third decomposition tank through a second decomposition tank discharging chute; an inclined notch is formed in the bottom end of the material lifting pipe, and the direction of the inclined notch is opposite to the rotating direction of the stirring device, so that materials can enter the material lifting pipe conveniently. According to the utility model, the stirring energy of the decomposition tank is used for lifting materials instead of material lifting air and an air compressor, so that the energy consumption required by the air compressor is reduced; the use of material lifting air is reduced, the contact between caustic alkali and air in the aluminum oxide production is reduced, the carbonization speed of the caustic alkali is reduced, the operation load of the causticization process is reduced, and the production cost is reduced.

A method for modifying a polymer membrane. The method comprises: pre-wetting a polymer membrane with a cross-linking agent solution, the cross-linking agent solution comprising a first cross-linking agent and a second cross-linking agent; irradiating the pre-wetted polymer membrane to initiate a cross-linking reaction; and washing the polymer membrane that has been subjected to the cross-linking reaction, and drying same to obtain a modified polymer membrane. In the method for modifying a polymer membrane in the present invention, two cross-linking agents are used to modify the polymer membrane, and a 3D network is formed on the surface and the bulk of the polymer membrane, thereby obtaining the modified polymer membrane. The modified polymer membrane in the present invention has low protein adsorption, stability towards caustic alkali, and stability during high-pressure sterilization and gamma sterilization; moreover, the overall mechanical performance is retained, making same capable of meeting the requirement of filter preparation for foldability.

The application discloses a preparation method and application of xanthate or composite xanthate, and belongs to the technical field of xanthate flotation reagent preparation. The preparation method comprises the following steps: firstly, carbon disulfide is added into a self-made kneader with a jacket, stirring is started, then a certain proportion of complex alcohol is added, salt water is opened for cooling, and stirring is continuously performed; nitrogen protection is started, and a weighed amount of caustic soda is added into the kneader in step one in batches for reaction preparation. The raw material source of the application is wide, the process operation is simple, the cost is controllable, the prepared composite xanthate has strong collecting capacity and selectivity, and good flotation indexes are obtained in the flotation test.

The invention discloses a method for removing inorganic salt in aluminum oxide mother liquor based on induced crystallization and graphene adsorption, and relates to the technical field of environment-friendly water treatment. The method comprises the following steps: standing the aluminum oxide mother liquor at room temperature for a period of time; after standing at room temperature for a period of time, adding a combined seed crystal into the aluminum oxide mother liquor for induced crystallization, and continuing standing at room temperature for 10 days; inorganic salt separated out in the induced crystallization process of the aluminum oxide mother liquor is separated and removed, and primary aluminum oxide mother liquor is obtained; wherein the combined seed crystal comprises a vanadium seed crystal, a caustic alkali seed crystal and an aluminum oxide seed crystal; and adding graphene into the primary aluminum oxide mother liquor, and stirring and adsorbing at room temperature to obtain the purified target aluminum oxide mother liquor. Through a combined process of induced crystallization and graphene adsorption, the problem of scaling of the aluminum oxide mother liquor is systematically solved, high efficiency, economical efficiency and environmental friendliness are achieved, a landing mother liquor purification solution is provided for the aluminum oxide industry, and practicability is achieved.

The invention discloses an alkali precipitation-coagulation treatment agent for alkali-minimization wastewater and a treatment method thereof, the alkali precipitation-coagulation treatment agent comprises 14 wt.%-16 wt.% of an Al2 (SO4) 3 aqueous solution of an alkali precipitation treatment agent I, 19 wt.%-21 wt.% of a CaCl2 aqueous solution of an alkali precipitation treatment agent II, 4 wt.%-6 wt.% of a polyaluminum chloride aqueous solution of a coagulation treatment agent I, and 0.08 wt.%-0.12 wt.% of a composite polymer aqueous solution of the coagulation treatment agent II, the weight ratio of the cationic starch to the cationic polyacrylamide is (4: 6)-(6: 4); the alkali precipitation-coagulation treating agent is used for sequentially carrying out alkali precipitation, coagulation and filter pressing dehydration on alkali-minimization wastewater to realize wastewater treatment, pollutants in the alkali-minimization wastewater are treated and TA in the wastewater is recycled on the premise of not adding acid and not adjusting pH, and meanwhile, caustic alkali in the wastewater can be reserved to the greatest extent.