50 results about "CAUSTIC ALKALIS" patented technology

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 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.

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 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.

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.

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.

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.

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 present application relates to an electrochemical system and method for capturing carbon dioxide, regenerating pure carbon dioxide, and / or converting captured carbon dioxide to biomethane, syngas, formic acid, and combinations thereof. More specifically, the present application relates to an electrochemical cell having an air cathode-proton or cation exchange membrane and a non-biological or biological anode in which captured carbon dioxide is reduced to carbonate, which is then regenerated to pure carbon dioxide or transferred to another chemical production module. The regenerated carbon dioxide may be purified, compressed, or stored for later use. The present application includes volatile fatty acids derived from carbohydrate-rich waste. The present application also includes the ability to regenerate caustic absorbers used in initial carbon dioxide capture.

The application relates to a method for producing vanadium concentrate and sodium oxalate from a Bayer process, comprising the following steps: providing a seed mother liquor in a Bayer production process, evaporating and concentrating the seed mother liquor to obtain a concentrated mother liquor; after cooling the concentrated mother liquor, adding vanadium salt seeds to the concentrated mother liquor for vanadium salt crystallization; performing solid-liquid separation on the concentrated mother liquor to obtain vanadium concentrate and a separated liquor; after heating the separated liquor to a predetermined temperature, increasing the caustic alkali concentration of the separated liquor; cooling the separated liquor with the increased caustic alkali concentration to perform sodium oxalate crystallization, and obtaining rich sodium oxalate crystals, wherein the caustic alkali concentration of the separated liquor is increased by at least one of the following two ways: evaporation and concentration or caustic alkali addition. The application can obtain high-grade vanadium concentrate and rich sodium oxalate crystals.

The application discloses an alkali-deduction wastewater alkali precipitation-coagulation treatment agent and a treatment method thereof. The alkali precipitation-coagulation treatment agent comprises alkali precipitation treatment agent I, 14wt.%-16wt.% of Al2(SO4)3 aqueous solution, alkali precipitation treatment agent II, 19wt.%-21wt.% of CaCl2 aqueous solution, coagulation treatment agent I, 4wt.%-6wt.% of polyaluminum chloride aqueous solution, and coagulation treatment agent II, 0.08wt.%-0.12wt.% of composite polymer aqueous solution, which is composed of cationic starch and cationic polyacrylamide with a weight ratio of 4:6-6:4. The alkali precipitation-coagulation treatment agent is used to treat the alkali-deduction wastewater by sequentially performing alkali precipitation, coagulation and pressure filtration dehydration, so that the pollutants in the alkali-deduction wastewater are treated without adding acid and adjusting pH, TA in the wastewater is recovered, and the caustic alkali in the wastewater is also maximally reserved.

The application provides a MER zeolite catalyst, a preparation method and application, and relates to the technical field of chemical synthesis and application thereof. The raw materials of the MER zeolite catalyst include a silicon source, an aluminum source, a structure directing agent, an auxiliary template agent, water and a caustic alkali; the structure directing agent is 1,1,2,6-tetramethylpiperidinium cation, the auxiliary template agent is a small-molecule organic base, and the molar ratio of the raw materials is controlled to be 1.0:0.02-0.05:0.05-0.3:0.02-0.19:5-20. The MER zeolite catalyst has a high silicon-aluminum ratio, excellent thermal stability and ion exchange performance, and performs outstandingly in ammonia-based selective catalytic reduction of nitrogen oxides (NH3-SCR), and is especially suitable for deNOx of exhaust gas of an internal combustion engine, and can effectively reduce NO x to non-toxic N2, and has a wide application prospect.

The present invention generally relates to a system and method for treating spent caustic effluent using chlorine dioxide solution. The system comprises a spent caustic storage tank for receiving spent caustic obtained from refinery operations; an acid storage container connected to the spent caustic storage tank for neutralizing free alkali content with a mineral acid to eliminate unwanted chemical reactions associated with free caustic present in spent caustic with ClO2; a heat exchanger unit engaged for reducing temperature of spent caustic to 35-45° C. from high temperature raised due to heat of neutralisation at least one of a cavitation (mixing) chamber or venturi mixing equipment mechanically connected downstream of the heat exchanger unit for adding ClO2 solution to the spent caustic solution to oxidize sulphide / thiols content for complete reduction of sulphide / mercaptane and reduction of 80-90% of COD.

Despite the abundance of scandium, its commercial applications continue to be limited by the absence of reliable, secure, stable and long-term production. The subject-matter disclosed herein provides for a method for extracting Rare Earth Elements (REE), scandium and / or Rare-Earth Oxides (REO) from ore and mineral concentrates, the method comprising: providing Rare Earth Elements (REE) and / or scandium bearing feedstock; a high-pressure caustic (HPC) leaching step, comprising leaching the feedstock in an alkali solution at a first temperature for a target period of time and at a given pressure to produce a leachate slurry; extracting a solid residue from the leachate slurry; leaching of the solid residue in a mineral acid to form a primary leach solution; extracting scandium and / or REE from the primary leach solution; and / or precipitating REE remaining in the raffinate to form a mixed REE-carbonate to thereby facilitate the extraction of REO.

A method for producing soda ash from flue gases involves capturing and processing the gases to remove contaminants and produce a high-purity soda ash. The process involves passing flue gas through a carbon capture system, where nitrates and sulfates are removed from the gas. The gas is then scrubbed with a rich caustic, causing a chemical reaction that removes carbon dioxide. The resulting product is then separated into a purified Na2CO3 product, essentially pure soda ash.

The invention relates to a non-corrosive degreasing concentrate and ready to use formulation. In particular, non-corrosive compositions capable of removing polymerized grease as effectively as some alkali metal hydroxide (i.e. caustic) based degreasers without requiring the use of personal protective equipment are disclosed.

The invention provides an electrochemical utilization method of water-soluble silicate waste liquid, and relates to the technical field of resource utilization of industrial waste liquid. The method comprises the following steps: S1, injecting the water-soluble silicate waste liquid into an electrolytic cell for electrolysis, generating silicic acid precipitate in an anode region, and enriching a caustic alkali solution in a cathode region; s2, carrying out multi-section circulating purification treatment on the enriched caustic alkali solution in the cathode region; and S3, separating and collecting the silicic acid precipitate in the anode region and the purified caustic alkali solution in the cathode region. Through combination of main electrolysis, three-section circulation purification and the cation exchange membrane, the purity of the caustic alkali and the silicic acid precipitate can be remarkably improved, and finally the high-purity caustic alkali solution with the concentration being 20-50 wt% and the silicic acid precipitate with the purity being larger than or equal to 99.9% are obtained.

The application discloses a method for preparing high-purity graphite by combining chemical method with physical method, and belongs to the technical field of graphene preparation. In order to solve the problems of high preparation cost and difficult treatment of preparation wastewater in the preparation of the high-purity graphite, the application combines the chemical method with the physical method, mainly changes the forms of silicon and aluminum impurities by using low-cost lime, changes the micron-sized impurities into nano-sized impurities, separates the graphite from the impurities through flotation, removes the metal oxides by using low-concentration hydrochloric acid, and finally the carbon content of the graphite product reaches more than 99.95%. The application has the advantages that the calcium hydroxide effectively replaces hydrofluoric acid and caustic soda, the cost is low, the wastewater is easy to treat, and the application is a technical model combining chemical beneficiation with physical beneficiation. The application is mainly used for the preparation method of the high-purity graphite.

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 aqueous caustic solution to form hydrogen (H2) gas and a reaction mixture containing dissolved sodium aluminate, removing a solid fraction from the reaction mixture to form a liquor solution, seeding the liquor solution with a seed material to precipitate ATH and form a suspension, isolating solid ATH from the suspension and washing the solid 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.

The application discloses a preparation method of electronic-grade barium hydroxide monohydrate and belongs to the technical field of electronic ceramic and new energy battery materials. The method effectively inhibits stress corrosion cracking and caustic embrittlement of a stainless steel crystallization kettle in the crystallization process of barium hydroxide monohydrate by controlling the slurry concentration and temperature, controlling the vacuum degree, controlling the material reaction time, using various additives, using seed crystals and other means, so that the conventional stainless steel crystallization kettle can be stably operated in a high-temperature strong-alkali environment for a long time. Moreover, the prepared barium hydroxide monohydrate has a purity of 99.5% or above, the generation of impure barium hydroxide is avoided, and the safe use of the barium hydroxide monohydrate material on electronic ceramic materials and new energy automobile batteries is ensured.

A method for the manufacture of high purity xanthate continuously in a system of reactors in a liquid organic medium by reacting caustic and alcohol to form alcoholate in a large circulating charge of previously reacted alcoholate at an elevated temperature, preferably no more than 110° C. A portion of the alcoholate is continuously withdrawn, cooled preferably to no more than 35° C. and rapidly dispersed with carbon disulfide to form xanthate in a large circulating charge of previously reacted xanthate while maintaining precise temperature control. Average contact time with byproduct water is 10 minutes. The product is continuously withdrawn and immediately dried to obtain in excess of 95% pure product.

The invention belongs to the technical field of mineral flotation, and particularly relates to a molybdenite flotation accelerant and a preparation method and application thereof.The preparation method of the molybdenite flotation accelerant comprises the following steps that citric acid (sodium), polyvinyl alcohol and gluconic acid (sodium) are dissolved in water according to the mass ratio of 1: (0.1-10): (0.1-10), and the total mass concentration is controlled to range from 20% to 80%; slowly adding caustic alkali into the mixture until the pH is increased to 10-14 and the temperature does not exceed 40 DEG C; carbon disulfide is slowly dropwise added under the stirring condition, the reaction temperature is kept at 0-40 DEG C, after the carbon disulfide is dropwise added, the temperature is increased to 10-40 DEG C at the speed of 1-3 DEG C / min, a heat preservation reaction is conducted for 1-6 h, cooling is conducted to the room temperature after the reaction is completed, and the molybdenite flotation accelerant is obtained. According to the method, the molybdenum grade in the concentrate can be remarkably improved, and meanwhile the grades of copper, lead and zinc in the concentrate are effectively reduced.

A process, system, and apparatus are provided for separating an oxygenated compound from a stream. More specifically, a stream comprising the oxygenated compound is fed into a cooling tower along with a caustic outlet stream comprising a metallic salt. Contact between the oxygenated compound and the metallic salt results in the conversion of a portion of the oxygenated compound into a derivative salt. The derivative salt and the unconverted oxygenated compound material are condensed by cooling and substantially removed from the cooling tower as an oxygenated compound outlet stream. The gaseous components of the stream, less a substantial portion of the oxygenated compound, are removed from the cooling tower as a cooling outlet stream.

The application relates to the technical field of wastewater treatment, and particularly discloses a hot galvanizing waste residue pickling waste liquid treatment method and a preparation method of a chloride ion adsorbent. The hot galvanizing waste residue pickling waste liquid treatment method comprises the following steps: adding the chloride ion adsorbent into waste residue pickling waste liquid with a pH value of 3-4, stirring and mixing to obtain a mixed solution; adding sodium alginate into the mixed solution, stirring and mixing, filtering, adjusting the pH value of the filtrate to 6-7 by using a caustic alkali, and obtaining treated waste residue pickling waste liquid; and the preparation method of the chloride ion adsorbent comprises the following steps: stirring and mixing amino silane coupling agent and water, then adding aluminum magnesium hydrotalcite, stirring and mixing, aging, washing with water, drying, grinding, and obtaining the chloride ion adsorbent. The hot galvanizing waste residue pickling waste liquid treatment method can effectively remove chloride ions and divalent iron ions in the waste residue pickling waste liquid, has high safety, and is suitable for large-scale promotion.