25 results about "Arsenite ion" patented technology

The invention provides a low-molecular soluble chelating collector as well as a preparation method and application thereof, and belongs to the technical field of mineral processing. According to the collecting agent, low-molecular-weight ethylene glycol terephthalate serves as a precursor, and isosorbide is introduced for a copolymerization reaction; glutamic acid is introduced as a branched chain unit, and the branching degree and reaction active site density of the molecular structure are remarkably improved by utilizing the polyfunctional group characteristic of glutamic acid. A rigid ring structure and an ether bond of the isosorbide endow the medicament with good water solubility and dispersity, and invalid curling of a macromolecular chain is avoided; the introduction of glutamic acid branched chains greatly increases the number of hydroxyl groups and amino groups capable of reacting with carbon disulfide, so that each molecule carries more xanthate groups, and the adsorption stability and coverage density of the molecule on the surface of arsenopyrite are enhanced. By means of the structure, xanthate functional groups are fully exposed, multi-tooth chelation is easily conducted on the xanthate functional groups and iron and arsenic ions on the surface of arsenopyrite, a strong hydrophobic surface layer is formed, and therefore the collecting selectivity is remarkably improved.

The invention discloses a method for deeply removing arsenic from a nickel sulfate solution, which comprises the following steps: adjusting the pH value by using nickel hydroxide to form colloid to preliminarily remove arsenic, oxidizing by using sodium sulfate, and adding polyferric sulfate to form ferric hydroxide colloid to deeply adsorb and remove arsenic, and is simple in process, convenient to implement in the production process, capable of greatly reducing the cost and reducing the environmental pollution, and suitable for industrial production. The method comprises the following steps: adjusting the pH value of a low-pH leaching solution / anolyte / crude nickel sulfate dissolving solution to 4.0 or more by using nickel hydroxide, carrying out filter pressing to remove slag, adding arsenic ions in a sodium persulfate oxidation solution, reacting for 30 minutes, adding polyferric sulfate, reacting for 30 minutes, and carrying out filter pressing to obtain a nickel sulfate solution which is almost free of arsenic, and the method is efficient, safe and environment-friendly.

The invention discloses a modified red-mud-based arsenic removal agent for acid mine wastewater as well as a preparation method and application of the modified red-mud-based arsenic removal agent. The preparation method of the arsenic removal agent comprises the following steps: placing the red mud in acid mine wastewater for modification reaction, and sequentially carrying out solid-liquid separation, washing and drying to obtain the arsenic removal agent, the mass volume ratio of the red mud to the acid mine wastewater is 1-15g / L; the pH value of the acidic mine wastewater is 1-3, and the concentration of ferric iron is 3-4g / L. According to the arsenic removal agent, red mud serves as a matrix, the arsenic removal capacity of the red mud can be greatly improved only through impregnation modification by means of the synergistic effect between the red mud and acid mine wastewater, and based on the excellent performance of the red mud-based arsenic removal agent, when the red mud-based arsenic removal agent is used for deep arsenic removal of wastewater, the arsenic removal capacity of the red mud can be greatly improved only through adjustment of the pH of a system. According to the present invention, the arsenic ions with different valence states can be completely and deeply removed by using the arsenic removal agent, and the test results show that the removal rate of the trivalent arsenic can achieve 94.47% and the removal rate of the pentavalent arsenic can achieve 99.99% when the pH value of the system is 12 when the arsenic removal agent is adopted to perform the deep arsenic removal on the wastewater.

The invention discloses a method for removing arsenic in copper smelting soot through mechanical force vulcanization. The method comprises the following steps: 1) putting the copper smelting soot and sodium sulfide into a ball mill for co-grinding; (2) a caustic soda solution is pumped into the obtained co-ground soot according to a certain flow speed, cyclic leaching is conducted, and selective separation of arsenic in the copper smelting soot is achieved; (3) after cyclic leaching, ferric chloride is added into a leaching solution, arsenic is stabilized, and a mixed solution is obtained; and 4) filtering the obtained mixed solution, collecting solids, washing, drying, and then carrying out ball milling and vacuum sintering in a protective atmosphere to obtain the arsenic-iron alloy. The method comprises the following steps: firstly, co-grinding the copper smelting soot and sodium sulfide, regulating and changing phases of arsenic and valuable metal elements in the soot by utilizing mechanical force and vulcanization, and promoting high-selectivity separation and leaching of the arsenic under mild conditions; the related recovery process is simple, convenient to operate, low in cost, high in arsenic ion selective removal efficiency and suitable for popularization and application.

The application discloses a paper-based arsenic ion synthetic biosensor based on a cell-free system and application thereof, and comprises a cell-free arsenic ion sensing module and a semi-quantitative paper-based detection chip. The cell-free arsenic ion sensing module is composed of a synthetic arsenate reduction module, an arsenic ion specificity sensing module, a high-gain transcription amplification module and a visual reporting module connected in sequence. The synthetic arsenate reduction module converts pentavalent arsenic into trivalent arsenic; the arsenic ion specificity sensing module recognizes trivalent arsenic and removes transcription inhibition; the high-gain transcription amplification module amplifies the signal through ecf11 cascade; and the visual reporting module outputs a colorimetric or fluorescent signal. The application integrates an engineered promoter and an ecf11 cascade amplification system in a cell-free system, greatly improves sensitivity and dynamic range and keeps low leakage. The paper-based chip can present different pattern arrangements according to arsenic concentration and is easy to read. The application provides an environmentally friendly, portable and easy-to-read innovative method for monitoring arsenic pollution in drinking water.

The invention provides a preparation method of an arsenic removal adsorbent, which comprises the following steps: preparing Bi (OH) 3-BiOOH blended powder, mixing the Bi (OH) 3-BiOOH blended powder with polyacrylonitrile and N, N-dimethylacetamide, dripping into small balls through a ball dripping device, drying, reacting with a mixed solution of CuCl2 and CeCl3, drying, reacting with a saturated tannic acid solution, and drying to obtain the arsenic removal adsorbent. The invention also provides application of the arsenic removal adsorbent in water treatment, especially in adsorption of trivalent arsenic and pentavalent arsenic in wastewater. The arsenic removal adsorbent disclosed by the invention has the advantages of high adsorption rate, high selectivity, high adsorption capacity and high cycle stability on pentavalent arsenic-containing ions and trivalent arsenic-containing ions in a water body, and is simple in synthesis process and beneficial to industrial production, application and popularization.

This invention provides a method for the co-reduction synthesis of zinc arsenide in an alkaline composite environment. The method innovatively uses a strongly alkaline solution as the basic electrolyte and simultaneously dissolves zinc oxide (ZnO) and arsenic trisulfide (As₂S₃) as the zinc and arsenic sources, respectively, to form Zn(OH)₄. 2‑ and AsS3 3‑ / AsO3 3‑ A multi-ion coexistence system was developed. By introducing multifunctional composite additives into this system, the electrodeposition process was synergistically regulated. Specifically, the reduction process of Zn(II) in situ modified the cathode interface, reducing the double-layer thickness and enhancing the adsorption and electron transfer of arsenite ions on the cathode surface. Simultaneously, the coupled co-deposition of arsenic and zinc effectively squeezed out the adsorption sites of water molecules on the cathode surface and the electron ratio of the hydrogen evolution reaction, thereby significantly suppressing the hydrogen evolution side reaction and the generation of highly toxic arsine (AsH3) gas. Ultimately, a uniform and well-bonded zinc arsenide deposition layer was obtained on the cathode surface.

The invention discloses a preparation method of high-purity phosphotriester, and belongs to the technical field of organic synthesis. The method comprises the following steps: firstly, cooling, crystallizing and purifying a phosphoric acid raw material, and respectively rectifying and purifying a tetraalkyl orthosilicate raw material and a reaction solvent to obtain a high-purity raw material and a solvent; then mixing high-purity phosphoric acid, high-purity tetraalkyl orthosilicate and a high-purity solvent, and carrying out one-step ester exchange reaction at 180-220 DEG C for 12-32 hours; and finally, carrying out post-treatment on the reaction liquid, and carrying out reduced pressure rectification on the obtained crude product to obtain a high-purity phosphotriester product. A chlorine-free raw material route is adopted from the source, and a deep purification process of a system before and after the reaction is combined, so that the content of arsenic ions in the product is effectively controlled to be 25 ppb or below, the content of chlorine ions is controlled to be 15 ppb or below, and the purity can reach 99.9999% or above. The method has the advantages of simple process, high yield and environmental friendliness, and is especially suitable for the fields with extreme requirements on impurity content, such as new energy batteries, electronic chemicals and the like.

A real-time monitoring system and method for inhibiting arsine evolution in electrodeposition de-arsenic process of copper electrowinning is provided. The system includes a PLC control module, a primary mother liquor real-time monitoring module, an de-arsenication circulating solution real-time monitoring module, a de-arsenicated solution real-time monitoring module, and an accurate regulation module. The present invention utilizes copper-arsenic electrowinning and concentration competition differences, with the difference and limit of copper arsenic concentration in the de-arsenication circulating liquid as the constraint indexs, and the PLC control module is configured to control monitoring modules to acquire copper and arsenic concentrations in a primary mother liquor, an de-arsenication circulating solution and a de-arsenicated solution in real time, to calculate and analyze required copper and arsenic ion concentrations in the de-arsenication circulating solution, and to accurately regulate dosage volume of the primary mother liquor with high copper and arsenic concentrations.

The invention relates to a high-arsenic zinc oxide smoke dust arsenic removal method which comprises the following steps: 1) copper recovery: adding a predetermined amount of a copper removal agent into a stirring tank filled with zinc oxide smoke dust pickle liquor, stirring and reacting for 30-60 minutes, and performing solid-liquid separation to obtain copper sludge and copper removal filtrate; (2) arsenic separation: the copper-removed filtrate enters an oxidation reaction stirring tank, ferric salt and an oxidizing agent are sequentially added for precipitation and arsenic removal, the stirring speed is controlled to be 200-400 r / min, the reaction temperature is 75-85 DEG C, and iron arsenate precipitation and arsenic-removed liquid are obtained through solid-liquid separation. According to the zinc oxide smoke dust arsenic removal treatment process, rapid separation of copper ions, zinc ions and arsenic ions is achieved, arsenic is stably removed, meanwhile, loss of the zinc ions is greatly reduced, used chemicals are low in price and easy to obtain, used equipment is conventional devices, and the process is simple, safe, efficient, small in energy consumption and low in cost.

The application provides an arsenic ion imprinted TiO2 photocatalytic material prepared by using a plant as a template, a preparation method and application thereof. The preparation method comprises the following steps: firstly mixing an alcohol solution of tetrabutyl titanate, a crosslinking agent and an initiator to obtain a TiO2 precursor solution; secondly mixing the TiO2 precursor solution with arsenic imprint template ions to obtain a TiO2 precursor solution loaded with the arsenic imprint template ions; thirdly mixing and then impregnating, in sequence, an activated plant template and the TiO2 precursor solution loaded with the arsenic imprint template ions, and then performing a solvothermal reaction to obtain a biological template TiO2; the arsenic imprint template ions are arsenite; and finally removing the biological template and the arsenic imprint template ions from the biological template TiO2 to obtain the arsenic ion imprinted photocatalytic material. The trivalent arsenic ion imprinted TiO2 photocatalytic material provided by the application can specifically remove trivalent arsenic anions in water, and has excellent arsenic removal effect.

A method of manufacturing a bone char absorbent includes the following steps. A drying step is performed on an initial bone material to form dried bone material. A torrefaction step or a co-torrefaction step is performed on the dried bone material to form torrefied bone material or a co-torrefied mixture, in which the torrefaction step and the co-torrefaction are performed at a heating rate of 10° C. / min to 20° C. / min to a torrefied temperature or a co-torrefied temperature of 175° C. to 300° C. for 15 minutes to 60 minutes. A cooling step is performed on the torrefied bone powders or the co-torrefied mixture to form the bone char absorbent. The mineral phase of the bone char absorbent includes carbonated hydroxyapatite, thereby enhancing the adsorption capacity for trivalent arsenic ions.

The present application relates to a method for preparing a carbon-based bulk As(III) oxidation-adsorption material, and belongs to the field of inorganic arsenic adsorption technology. A method for preparing a carbon-based bulk As(III) oxidation-adsorption material, the specific steps of which are as follows: taking bamboo stems, immersing them in a stannous chloride and hydrochloric acid solution to obtain a sensitized biomass matrix; immersing the sensitized biomass matrix in a mixed solution of ammonia and silver nitrate to obtain an activated biomass matrix; transferring the activated biomass matrix to a mixed solution of copper ions and a reducing agent to obtain a copper-plated biomass; immersing the copper-plated biomass in a ferrous chloride solution and freeze-drying it to obtain an iron-doped copper hydroxide-modified biomass; transferring the dried iron-doped copper hydroxide-modified biomass to a tubular furnace, pyrolyzing it under inert gas protection to obtain a high-performance carbon-based bulk As(III) oxidation-adsorption material; and efficiently oxidizing and adsorbing arsenite ions.

The application relates to the technical field of optoelectronic devices, and discloses a vertical cavity surface emitting laser and a preparation method thereof. The preparation method comprises the following steps: providing a substrate layer; forming an epitaxial structure on one side surface of the substrate layer, the epitaxial structure being a gallium arsenide-based structure and comprising a first mirror layer, a first confinement layer, an active layer, a second confinement layer and a second mirror layer which are arranged in a stack mode; performing selective arsenic ion implantation on one side of the second mirror layer to form a ring-shaped ion modulation layer which penetrates into a partial thickness of the second mirror layer, a first light hole for current injection and light emission is formed in the ion modulation layer, the ion modulation layer has a resistivity greater than that of the second mirror layer and a refractive index less than that of the second mirror layer; forming a contact layer on the epitaxial structure to cover the second mirror layer and the ion modulation layer; and forming a first electrode on the contact layer, the first electrode being in electrical communication with the contact layer and being misaligned with the first light hole. In the application, the ion modulation layer formed by arsenic ion implantation is high-resistance, stable and stress-free, and can meet the demand of high-speed optical communication.

The application discloses a method for removing trivalent and pentavalent arsenic in sewage by in-situ generation of iron-manganese sulfide, and belongs to sewage treatment technology, and is characterized by comprising the following operation steps: (1) adding soluble divalent manganese salt, soluble ferrous salt, sulfur ions and phosphate into a reactor containing sewage containing trivalent arsenic and pentavalent arsenic, and mixing; (2) stirring the reaction system, producing nanometer iron-manganese sulfur composite colloid material, and promoting the produced nanometer iron-manganese sulfur composite colloid material to form a precipitate with trivalent arsenic and pentavalent arsenic ions; and (3) performing solid-liquid separation on the precipitate, and the supernatant is sewage from which arsenic elements are removed. The technology has the advantages of simple technological process, low cost, good arsenic removal effect and obvious advantages in practical application, and has a wide application prospect.

The invention relates to the technical field of chemical detection, in particular to a method for detecting arsenic ions based on yellow carbon dots. The method comprises the following steps: preparing nitrogen / sulfur co-doped yellow carbon dots Y-CDs from o-phenylenediamine and thiourea, adding an As < 3 + > solution with gradient concentration into the yellow carbon dots Y-CDs, mixing and reacting to obtain a mixed solution, and summarizing a regression equation according to a linear relationship between the fluorescence intensity of the mixed solution at 575nm and the logarithmic value of the As < 3 + > concentration, so as to quantitatively analyze As < 3 + > in a sample to be detected. According to the method, the detection limit is 1 mu M, the quantitation limit is 3.3 mu M, the recovery rate is 95-112%, the operation is simple and convenient, the cost is low, and the detection requirements of arsenic ions can be met.

The application relates to the technical field of biomedical engineering, and discloses a sodium alginate hydrogel loaded with copper arsenite nanoparticles as well as a preparation method and application thereof. The hydrogel comprises a sodium alginate hydrogel matrix and copper arsenite nanoparticles loaded therein, the copper arsenite nanoparticles comprise Cu2+, arsenite ions and PLGA-PEG-NH2, the sodium alginate hydrogel loaded with the copper arsenite nanoparticles is used for in-situ solidification to form a drug storage after intratumoral injection. The application constructs a nanoparticle self-assembly system based on PLGA-PEG-NH2, uniformly loads a complex formed by arsenite ions and copper ions in the PLGA-PEG-NH2 carrier material, forms copper arsenite nanoparticles with uniform and controllable particle sizes through a self-assembly process, the nanoparticles form stable complexes through coordination complexation between Cu2+ and As3+, and have the characteristics of specific dissociation in a tumor acid microenvironment.

This invention discloses an iodonium salt photoinitiator and its application in the preparation of treatment-free CTP thermal printing plates. The general formula of the iodonium salt photoinitiator is shown in Formula 1, wherein R1 is a substituted or unsubstituted alkyl or substituted or unsubstituted alkoxy group having 2-9 carbon atoms, and R2, R3, R4, and R5 are independently hydrogen atoms, alkyl groups, halogens, hydroxyl groups, carboxyl groups, amino groups, alkoxy groups, ester groups, nitro groups, and are tetraphenylboron ions, boron tetrafluoride ions, boron hexafluoride ions, phosphorus hexafluoride ions, arsenic hexafluoride ions, tellurium hexafluoride ions, halide ions, perchlorate ions, acetate ions, or trifluorosulfonate ions. The iodonium salt photoinitiator with the structure of this application can be used to prepare treatment-free CTP thermal printing plates, and can improve digital imaging speed and reduce crystals in the precursor of the formed negative lithographic printing plate. At the same time, the prepared treatment-free CTP thermal printing plate has excellent imaging speed and printing durability.

This invention provides a fluorescent probe for detecting trivalent arsenic ions, its preparation method, and its application. The fluorescent probe has a structural formula selected from at least one of Formula 1, Formula 2, Formula 3, or Formula 4. The fluorescent probe exhibits high fluorescence emission intensity, good sensitivity and response speed for detecting trivalent arsenic ions, and can achieve real-time dynamic analysis of trivalent arsenic ion concentration in situ.

The invention relates to a method for producing scorodite from a solution comprising arsenic and sulfuric acid without the use of a neutralizing agent, comprising the following steps: i. Subjecting a first arsenic solution comprising arsenic and sulfuric acid in the form of a mixture of arsenite ions and arsenate ions to an oxidation treatment, oxidizing the arsenite ions into arsenate ions, a second arsenic solution is obtained; ii, adding a first solution containing ferrous ions into the second arsenic solution to generate a third arsenic solution; iii. Adding a first portion of magnetite to the third arsenic solution to adjust the molar ratio of iron ions to arsenate ions to 0.3-1 to generate a first arsenic slurry; iv. Adding to the first arsenic slurry a portion of the scorodite slurry recycled from step viii as a nucleation matrix for scorodite particles, obtaining a first scorodite slurry of from 2% w / w to 15% w / w; v, heating the first scorodite slurry to 80 DEG C to 90 DEG C; vi, the first scorodite slurry is kept at the temperature of 80 DEG C to 90 DEG C for 5 h to 48 h, and second scorodite slurry is obtained; vii, conveying the second scorodite slurry to a solid-liquid separation step to obtain third scorodite slurry and a treated solution; viii. Recycling a first portion of the third scorodite slurry to step iv; and (ix) filtering a second portion of the third scorodite slurry.

The invention relates to a metal-semiconductor-based composite material, a preparation method thereof and application of the metal-semiconductor-based composite material in arsenic ion detection. The composite material disclosed by the invention comprises Bi2SeO5-Ag (at) Ag < + > NSs, and comprises a Bi2SeO5-Ag NSs heterojunction and Ag < + >, the Bi2SeO5-Ag NSs heterojunction comprises a Bi2SeO5 nanosheet and silver nanoparticles loaded on the surface of the Bi2SeO5 nanosheet. The preparation method comprises the following steps: preparing a bismuth selenate nanosheet, forming a silver nanoparticle layer on the surface of bismuth selenate, soaking the bismuth selenate nanosheet on the silver nanoparticle layer to combine silver ions, mixing a solution containing arsenic ions with a compound with silver nanoparticles on the surface and an aggregation agent, enriching on the surface of tinfoil, and drying, thereby obtaining the bismuth selenate composite material. And irradiating light to the center of the to-be-detected arsenic ion water drop dripped on the aluminum foil by using a laser light source. And finally, detecting the enriched arsenic ions by using Raman spectrum detection to obtain As (III) As (V) and a specific Raman peak signal.

The invention discloses a harmless co-treatment method for oxidative cyanidation tailings and non-ferrous smelting arsenic-containing waste acid, and belongs to the technical field of metallurgical industry solid waste comprehensive recycling and heavy metal arsenic pollution abatement. The method comprises the following steps that water is added into the oxidative cyanidation tailings to obtain ore pulp, and the ore pulp is subjected to secondary treatment; adjusting the pH value of the ore pulp to be alkaline by using sodium hydroxide so as to prevent the generation of hydrogen cyanide gas, and obtaining cyanidation tailing adjusted ore pulp; adding a decyanation agent and an auxiliary agent into the cyanidation tailing adjusting ore pulp, and reacting to obtain a solid-liquid mixture A; filtering the solid-liquid mixture A to obtain decyanated tailings and decyanated liquid, uniformly mixing the decyanated tailings with non-ferrous smelting arsenic-containing waste acid, and reacting to obtain a solid-liquid mixture B; and filtering the solid-liquid mixture B to obtain an arsenic-containing solid and arsenic-removed filtrate. According to the method, the oxidizing cyanidation tailings are used as an arsenic removal reagent and neutralized with the arsenic-containing waste acid for nonferrous smelting, and meanwhile, iron ions and calcium and magnesium ions separated from the oxidizing cyanidation tailings can form stable precipitates such as scorodite and the like with arsenic ions in the arsenic-containing waste acid, so that the effect of treating waste with waste is achieved.

The invention relates to the technical field of optoelectronic devices, and discloses a vertical cavity surface emitting laser and a preparation method thereof. The preparation method comprises: providing a substrate layer; an epitaxial structure is formed on the surface of one side of the substrate layer, and the epitaxial structure is a gallium arsenide-based structure and comprises a first reflector layer, a first limiting layer, an active layer, a second limiting layer and a second reflector layer which are stacked; selective arsenic ion implantation is carried out on one side of the second reflector layer to form an annular ion modulation layer penetrating into the second reflector layer by partial thickness, a first light hole for current injection and light emission is formed in the annular ion modulation layer, the resistivity of the first light hole is larger than that of the second reflector layer, and the refractive index of the first light hole is smaller than that of the second reflector layer; forming a contact layer covering the second reflector layer and the ion modulation layer on the epitaxial structure; a first electrode is formed on the contact layer in electrical communication with the contact layer and offset from the first aperture. In the invention, the ion modulation layer formed by arsenic ion implantation is high-resistance, stable and stress-free, and meets the requirement of high-speed optical communication.

The invention discloses a method for detecting the arsenic content in a water body by using a microfluidic-ultraviolet visible spectrum, and particularly relates to a detection technology for the arsenic content in the water body. According to the method, the principle that arsenite and potassium iodate generate elemental iodine under the acidic condition, and the elemental iodine can oxidize rhodamine B (RhB) in a sulfuric acid medium under the catalysis of a potassium bromide solution so as to fade the rhodamine B is utilized, a microfluidic device and an ultraviolet-visible spectrophotometric technology are combined, spectrum detection is carried out on the faded rhodamine B generated by reaction, and the detection result is accurate. And comparing with a standard curve to obtain the arsenic concentration. The detection range of the method is 0.1-20 [mu] g / L, the method covers the concentration limit value (10 [mu] g / L) of the arsenic ions in the drinking water by the World Health Organization, and the detection limit is 0.096 [mu] g / L and is lower than that of most other methods.

The invention relates to a method for intensively removing iron and arsenic in a zinc sulfate solution through an ultrasonic synergistic functional composite neutralizer, and belongs to the technical field of hydrometallurgy solution purification. The method comprises the following steps: heating a zinc sulfate solution containing ferrous ions and arsenic ions to 60-95 DEG C, adding an oxidizing agent, uniformly mixing, then introducing ultrasonic waves, adding a rapid kinetic regulator, carrying out ultrasonic-enhanced initial oxidation reaction for 5-10 minutes, and rapidly adjusting the pH value of the solution to 2.8-3.5 to obtain a mixed solution; at the temperature of 60-95 DEG C, slowly adding an accurate precipitation accelerant and a buffer stabilizer into the mixed solution, uniformly mixing, carrying out ultrasonic-enhanced continuous oxidation reaction for 15-20 minutes, stably raising the pH value of the solution to 3.8-4.5, continuing to react for 10-30 minutes, and carrying out solid-liquid separation to obtain precipitation slag and a solution subjected to iron and arsenic precipitation. The rapid dynamic regulator is responsible for rapidly starting the reaction and creating initial conditions for goethite nucleation; the accurate precipitation accelerant ensures pH stability and deep co-precipitation of impurities in the middle and later periods of the reaction; the buffer stabilizer effectively eliminates local over-alkali and maintains the system stability.