61 results about "Acidity/alkalinity" patented technology

Adhesive compositions including a multivalent metal salt, an multidentate acidic organic compound, and an aqueous medium are disclosed. The multivalent metal salt and multidentate acidic organic compound can include, as a mixture, a carbonate salt and / or carbonic acid. The aqueous medium can include pH adjusting agent such as sodium hydroxide. The adhesive composition, upon curing, can have a porosity of 10-50%. The adhesive composition, upon curing, can include a plurality of pores. The adhesive composition can be porous, and upon curing can have a plurality of pores having a pore size of between 20 μm to 200 μm. Methods of producing the adhesive composition are disclosed. Methods of using the adhesive composition are further disclosed.

The invention is suitable for the application field of electrolyte acidity determination, and provides a method for determining the acidity of an all-vanadium electrolyte based on a complexing mass difference method, and the method comprises the following steps: taking the all-vanadium electrolyte, and diluting the all-vanadium electrolyte into a pretreated all-vanadium electrolyte with the concentration of 0.05-0.1 mol / L; adding 1.5-2mL of a complexing masking reagent with the molar concentration of 1.5-2mol / L, weighing, and recording as M1; stirring and titrating, weighing and recording as M2; a quantitative determination method of mass difference is used for calculation, and the formula is {(M2-M1)-0.05} / A * C. In conclusion, a mass difference quantitative determination method is adopted, the vanadium complexing masking reagent is added, the adding amount and the pH value of the vanadium complexing masking reagent are controlled, a stable complex is formed through the complexing masking reagent, vanadium ions and impurity ions, the oxidation-reduction reaction and the precipitation reaction of the complex and sodium hydroxide are inhibited, and the accuracy of the acidity value of the all-vanadium electrolyte is improved.

The invention discloses a high-acidity complex flow state multi-parameter on-line monitoring system, an acid mixing vehicle and a method.The system comprises an acid mixing tank, the acid mixing tank is communicated with a powder pipeline, an acid pipeline, a clear water pipeline, a liquid medicine pipeline and a discharge pipeline, and the powder pipeline, the acid pipeline, the clear water pipeline, the liquid medicine pipeline and the discharge pipeline are all provided with monitoring devices; and the monitoring device is electrically connected with the intelligent control system. The device can record the instantaneous quantity and the cumulant quantity of the acid liquor, the clear water and the chemical additive on line in real time, generate an operation curve and a report at the same time, and can monitor the viscosity, the density and the acidity of the prepared acid liquor on line so as to confirm whether the quality of the acid liquor is qualified or not. According to the invention, monitoring data can be archived, later review and tracing are facilitated, manual sampling analysis is not needed, and potential safety hazards are eliminated.

The invention discloses a method suitable for waste acid purification and acidity improvement in the titanium dioxide industry, and belongs to the field of waste acid treatment. The invention aims at solving the problem of sulfuric acid waste caused by simple treatment of waste acid and solving the technical problems caused by precipitation in the sulfuric acid concentration process. The method comprises the following steps: S1, uniformly mixing cyclohexanol hexaphosphate, phosphate and a flocculating agent according to a certain proportion to obtain a purifying agent; s2, pouring the waste acid accounting for 30% of the total volume of the waste acid into the purifying agent, and stirring; s3, pouring the residual waste acid, and stirring; and S4, then carrying out filter pressing. According to the invention, waste of sulfuric acid caused by a neutralization precipitation method is avoided; the content of metal ions in the activated acid is low, and the problems of regular management and cleaning and equipment maintenance caused by precipitation are effectively avoided during evaporation, concentration and recycling.

This utility model belongs to the field of stainless steel pipe pickling technology, specifically relating to an acid concentration adaptive automatic pickling tank, including a tank body. A perforated plate is fixedly connected to the inner wall of the tank body. An acidity detector is embedded in the tank body. A sealing baffle is detachably connected to the tank body. A disturbance component is arranged below the perforated plate. A reflux component and a vibration component are arranged on the side wall of the tank body. The disturbance component includes a motor, which is fixedly mounted on a mounting frame. A bevel gear is fixedly connected to the output shaft of the motor. This acid concentration adaptive automatic pickling tank, through the use of the disturbance component, uses a motor to drive the agitator blades to rotate, agitating the acid solution. The reflux component, through synchronous transmission, rotates the spiral blades, transporting the acid solution from the bottom of the tank to the top, promoting the circulation and mixing of the upper and lower layers of acid solution, significantly reducing concentration stratification and avoiding excessive or insufficient acid replenishment due to local concentration deviations, thus ensuring stable pickling results.

The present invention discloses a method for preparing N-hydroxysuccinimide. The method uses a weakly acidic cation exchange resin as a catalyst. By reducing the acidity of the reaction system, product decomposition can be avoided, thereby improving product yield and quality. The method also reduces the reaction temperature, lowers equipment anti-corrosion requirements, extends equipment service life, reduces energy consumption, and is more conducive to industrial implementation. Furthermore, the catalyst is recyclable and does not require the addition of a stabilizer, making it more environmentally friendly.

The invention discloses a metal-doped VOOH nano-enzyme material with a hollow spherical shell structure as well as a preparation method and application of the metal-doped VOOH nano-enzyme material, and belongs to the technical field of nano-materials and biological catalysis. The invention aims to solve the problems that the peroxidase-like activity of the existing pure-phase VOOH nano material is relatively limited, the electronic structure of the pure-phase VOOH nano material is not in the optimal state of catalyzing H2O2 decomposition, and the adsorption / desorption energy barrier of a reaction intermediate is relatively high. The chemical general formula of the metal-doped VOOH nano-enzyme material with the hollow spherical shell structure is M-VOOH, and M is a doped metal element. The preparation method comprises the following steps: 1, dissolving a precursor; 2, acidity adjustment; 3, doping metal; and 4, reduction and crystallization. According to the application, the catalyst serves as a peroxidase-like catalyst to catalyze decomposition of hydrogen peroxide.

The standard substance for simulating the acidity of the product oil comprises benzoic acid and low-carbon alcohol, the purity of the benzoic acid is not lower than 99.8 wt%, and the low-carbon alcohol is one of methanol, ethanol or propanol; the concentration of the standard substance is 1 to 10 mgKOH / 100 mL, preferably 2 to 7 mgKOH / 100 mL. The acidity standard substance is good in accuracy, fills the blank that no acidity standard substance exists at present, and has wide application prospects in the aspects of calibration of a petroleum product acidity tester, confirmation of an acidity measuring method, instrument quality control and the like.

The present invention relates to a reforming catalyst comprising: - a porous support comprising essentially alumina; - platinum in a content comprised between 0.2 and 0.6% by weight; - at least one VA group element chosen from antimony, bismuth and phosphorus, in a content comprised between 0.2 and 0.8% by weight; - at least one IA group element chosen from lithium, sodium and potassium, in a content comprised between 0.004 and 0.2% by weight; - at least one IIIA group element chosen from gallium, indium and thallium, in a content comprised between 0.02 and 0.6% by weight.

The invention discloses a method for efficiently reducing elemental selenium from selenium-containing leachate based on ferrous sulfate, which comprises the following steps: taking the selenium-containing leachate obtained by oxidation and acid leaching, and adjusting the acidity of the leachate to 0.5-1.1 mol / L; ferrous sulfate is added into the acid-adjusted selenium-containing leachate according to the liquid-solid ratio of 2 mL: (1.0-1.4) g for a reduction reaction, the reduction reaction temperature ranges from 70 DEG C to 90 DEG C, the reduction reaction time ranges from 40 min to 80 min, and a reaction product I is obtained; and separating the precipitate of the reaction product I, washing and drying to obtain the elemental selenium. According to the method disclosed by the invention, the elemental selenium is extracted by reducing the selenium-containing leachate by adopting ferrous sulfate, and the reduction rate of selenium can reach 91% or above under limited conditions; under optimized conditions, the selenium reduction rate can reach 95.87%, which is significantly superior to that of existing processes such as a microbiological method.

The invention discloses an acidity detection device for electronic-grade fluorocarbon gas and a use method of the acidity detection device. The detection device comprises an absorption detection unit, an absorption liquid supplementing unit, a detection liquid supplementing unit and a control unit, the absorption detection unit comprises two absorption bottles, the first absorption bottle is connected with the second absorption bottle in series, a pipeline from gas to be detected is inserted into the first absorption bottle, a first gas distributor is arranged at the insertion end, and a second gas distributor is arranged at the bottom end of the pipeline from the first absorption bottle to the second absorption bottle; the absorption liquid supplementing unit comprises an alkali liquid storage tank and a first peristaltic pump; the detection liquid supplementing unit comprises an acid standard solution storage tank and a second peristaltic pump; the control unit comprises three pH meters which are respectively used for detecting the pH value of the liquid in the first absorption bottle, the pH value of the liquid in the second absorption bottle and the pH value of the acid standard solution. The acidity detection device and the detection method are high in automation degree, can be used for detecting fluorocarbon gas with the acidity content of 0.01 ppm or below, and are high in accuracy.

The invention is applicable to the technical field of electrochemical analysis, and provides a method for measuring the acidity of an iron-chromium electrolyte based on a complexing mass difference method.The method comprises the following steps that a pretreated iron-chromium electrolyte is prepared, a complexing reagent playing a complexing role on iron and chromium ions is added into the pretreated iron-chromium electrolyte, and the weight is recorded as M1; the pretreated iron-chromium electrolyte added with the complexing reagent is stirred, then a standard alkali solution is dropwise added, after titration is stopped, the weight is weighed and recorded as M2, a quantitative determination method of mass difference is used for calculation, and the acidity calculation formula is {(M2-M1)-K} * C. In conclusion, a quantitative determination method for the quality difference is adopted, and the complexing reagent containing carboxyl is added, so that the side reaction of iron and chromium ions is reduced and avoided, the selectivity and the accuracy of determining the acidity of the iron-chromium electrolyte are improved, and the rapid and accurate determination of the free acid is realized.

Process for the rejuvenation of a catalyst comprising a metal from group VIII, a metal from group VIb and an oxide support not comprising zeolite, comprising the following stages:a) said catalyst is regenerated at a temperature of between 360° C. and less than 420° C. so as to obtain a regenerated catalyst comprising a certain content of carbon and sulfur and a proportion of crystalline phase determined by X-ray diffraction and characterized by a ratio of less than 0.6,b) said regenerated catalyst is brought into contact with an aqueous solution consisting of water, of phosphoric acid and of an organic acid having each acidity constant pKa greater than 1.5,c) drying is carried out at a temperature of less than 200° C.

The present application relates to the technical field of computer, and provide a kind of water regulating method and system, the method comprises: obtaining turbidity sensor value and acid-base sensor value;Based on turbidity sensor value and acid-base sensor value respectively fuzzy operation, obtain turbidity fuzzy set and acidity fuzzy set;Based on turbidity fuzzy set and acidity fuzzy set, determine the incoming water credibility set, and based on incoming water credibility set and preset fuzzy control table, determine first credibility output;Based on first credibility output, determine target new incoming water flow, and with target new incoming water flow control new incoming water flow into water regulating system.The water regulating method provided in the embodiment of the present application is in the process of water regulating, according to turbidity sensor value and acid-base sensor value, fuzzy control operation is carried out, target new incoming water flow is determined, so as to control the amount of water flowing into water regulating system according to target new incoming water flow scientifically and accurately, so as to reduce water consumption, realize energy saving and emission reduction.

The application discloses a method for detecting the acidity of a circulating solution of electro-deposited cobalt, which comprises the following steps: removing oxidizing substances in the circulating solution of electro-deposited cobalt by potassium iodide in an acidic medium; reacting the potassium iodide with potassium iodate and acid to generate iodine molecules; titrating with a sodium thiosulfate standard solution until the solution changes from blue or blue-black to the original color of the solution, which is the end point; and calculating the acidity content according to the mass balance. The method can effectively remove the oxidizing substances in the solution to be measured, avoid the interference with the determination of the acidity content, and make the detection result more accurate. The sodium thiosulfate is innovatively applied to the detection of the acidity of the circulating solution of electro-deposited cobalt, and the sodium thiosulfate titration is used to replace the commonly used sodium hydroxide titration method, so that the interference of the original color of the light red solution with the color judgment of the end point of the sodium hydroxide (phenolphthalein as an indicator) is avoided.

The invention discloses a preparation method of a nitrogen removal material by a sulfur autotrophic denitrification method. The nitrogen removal material is prepared from elemental sulfur, calcium carbonate, a binder and trace elements. According to the invention, the influence of the manufacturing process does not float on the surface of a water body like elemental sulfur, the filler can slowly release effective components in the filler according to the total nitrogen content in the water body, and meanwhile, main components of the material can participate in actual reaction and do not generate precipitates, so that a user does not need to worry about residual waste residues after actual operation; wherein calcium carbonate not only provides an inorganic carbon source for sulfur autotrophic bacteria, but also can fully neutralize acidity generated in autotrophic denitrification; the problems that elemental sulfur particles can be discharged along with water flow, sodium thiosulfate needs to be quantitatively added, and waste residues left after sulfur-containing ore reaction need to be additionally treated are effectively solved, and the adverse effect of elemental sulfur type autotrophic denitrification acid production on the reactor is also solved.

A solid alumina composition is prepared from an acid-treated precursor composition, the precursor composition having an alumina hydroxide (Al(OH)3), aluminum oxyhydroxide (AlO(OH)), or a mixture thereof; where the solid alumina composition includes η-alumina characterized by having an X-ray powder diffraction pattern with peaks at 19.6±0.5° 2θ and 66.8±0.5° 2θ; and where the solid alumina composition has an acidity measured by an NH3-TPD test, characterized by: (1) an acid site density ranging from about 200 to 800 μmol / g; and / or (2) an acid strength distribution of: about 20%-70% weak acid sites (such as about 30-50%, about 30-40%, or about 35-40%), about 30%-80% medium acid sites (such as about 50-70%, about 60-70%, or about 60-65%), and about 0-20% strong acid sites (such as about 0-10%, about 0-5%, or about 0-2%).

The invention discloses a method for selectively leaching germanium based on acidity gradient regulation and control, and relates to the technical field of hydrometallurgy and rare metal recovery. Comprising the following steps: performing neutral leaching on a germanium-containing raw material to obtain neutral leaching liquid and neutral leaching residues; the neutral leaching residues are subjected to weak acid leaching, and weak acid leaching liquid and weak acid leaching residues are obtained; the weak acid leaching residues are subjected to high-acid leaching, meanwhile, sulfur dioxide is introduced for enhanced leaching, high-acid leaching liquid and high-acid leaching residues are obtained, the high-acid leaching residues are pulpified through the high-acid leaching liquid, and high-acid germanium-rich ore pulp is obtained; the high-acid germanium-rich ore pulp is subjected to ultrahigh-acid leaching, and ultrahigh-acid leaching liquid and ultrahigh-acid leaching residues are obtained; wherein the germanium recovery rate in the ultra-high acid leaching solution is greater than 80%. According to the method, the acidity, the temperature and the reduction leaching conditions are accurately controlled, the germanium recovery rate is maximized, selective separation is achieved, the process is simple, the cost is low, remarkable economic benefits are achieved, and the method has wide application prospects in the field of resource reutilization of germanium-containing smoke dust, germanium-containing slag and other complex raw materials.

The invention relates to a catalyst comprising 0.1-5 wt% ruthenium and 0.1-2.0 wt% sodium on a zirconia support. Such catalysts have low levels of acid sites on the zirconia support and are useful in a range of applications, particularly those requiring a support with low acidity. Also disclosed is a process for preparing the catalyst by impregnation of a zirconia support with a co-impregnation support comprising ruthenium oxalate and sodium citrate.

The invention belongs to the technical field of atomic absorption spectrometry analysis, and particularly relates to a method for rapidly determining trace Pb in a complex sample under high acidity based on atomic absorption spectrometry, in particular to an analysis method for accurately and rapidly determining trace Pb in cosmetics. According to the method for rapidly determining the trace Pb in the complex sample under the high acidity based on the atomic absorption spectrometry, the HCl concentration of a test system can be greatly improved to 10% by adopting a designed chemical atomizer and optimizing the conditions of reduction reaction; the method breaks through the bottleneck that trace Pb in a few simple samples can only be measured under low acidity by a hydride generation method, so that the chemical reaction of Pb and NaBH4 can be stably carried out under high acidity, the problem of testing trace Pb in complex samples is solved, and the method is high in sensitivity, simple and rapid to operate and reliable in test result.

The application relates to the field of chemical detection methods, and particularly discloses a direct complexing titration method for zirconium in yttrium-zirconium composite oxide in a sulfuric acid medium. The direct complexing titration method for zirconium in yttrium-zirconium composite oxide in a sulfuric acid medium is as follows: ZrO2 is fused by using concentrated sulfuric acid to generate zirconium sulfate, water is added for dilution, concentrated sulfuric acid is added dropwise to increase the acidity of a test solution, EDTA solution is added dropwise under high-acidity high-[ZrO 2+ ] conditions to complex and mask a large amount of ZrO 2+ ; water is further added for dilution to reduce the acidity of the test solution, EDTA solution is added dropwise under low-acidity low-[ZrO 2+ ] conditions to complex ZrO 2+ , and obvious bright yellow jumps of dimethylphenol orange indicator appear at the end point. The method can be used for rapid detection of various yttrium-zirconium composite oxides, and has the advantages of strong operability, high recovery rate and sensitive titration end point.

The invention relates to the technical field of wet smelting of non-ferrous metals, in particular to a method for wet separation of molybdenum and rhenium and enrichment extraction of rhenium in a high-acid solution, which comprises the following steps: adding a phosphorus source into a raw material solution containing molybdenum and rhenium, and adjusting the acidity to a high-acid environment with the hydrogen ion concentration greater than or equal to 1mol / L; extracting rhenium from the acidity-adjusted raw material liquid containing molybdenum and rhenium by using an amine extraction system to obtain a rhenium-rich organic phase; the amine extraction system comprises an amine extraction agent and a modifier; and carrying out reverse extraction on the rhenium-rich organic phase to obtain a rhenium product. According to the method, the phosphorus source is added into the raw material liquid containing molybdenum and rhenium, so that phosphate ions are hydrolyzed from the phosphorus source, molybdenum can be effectively prevented from being extracted by an extraction system, the selectivity of the extraction system to rhenium is greatly improved, and the recovery rate of rhenium and the molybdenum and rhenium separation effect are improved; the problems that in the prior art, an extraction system is difficult to adapt to molybdenum-rhenium separation under the high acid concentration, the rhenium recovery rate is low, the rhenium-molybdenum separation effect is poor, and a high-acid-concentration solution cannot be treated are solved.

A catalyst preparation method, the method steps comprising a) preparing a co-impregnation solution of both ruthenium oxalate and sodium citrate in water, b) adding the co-imprecnation solution to a Zr

This invention proposes an automatic dosing device for treating mine pit water inflow, relating to the field of water treatment technology. The invention incorporates a pH sensor to detect the acidity or alkalinity of the wastewater. When the wastewater is acidic, the pH sensor controls the automatic acid treatment control component, which adjusts the dosing rate based on the wastewater's acidity. The dosing rate increases when the acidity is high and decreases as the acidity neutralizes. Dosing stops when the acidity is neutralized. When the wastewater is alkaline, the pH sensor controls the automatic alkali treatment control component to achieve acid-base neutralization. By utilizing the pH sensor, the acidity or alkalinity of the wastewater can be accurately and in real time. In acidic or alkaline conditions, the automatic control component adjusts the dosing rate according to the actual acidity or alkalinity, ensuring the correct dosage and achieving acid-base neutralization, thus reducing chemical waste.

The invention discloses an ultra-trace thallium analysis system and method. The ultra-trace thallium analysis system comprises a pretreatment unit, a separation and enrichment unit, a pH regulation unit and a detection unit. The pretreatment unit is used for filtering, acidifying and oxidizing a water sample to be treated to obtain a pretreated water sample; the separation and enrichment unit is used for enriching thallium ions in the pretreated water sample and separating out interfering ions; the pH adjusting unit reduces the acidity of the enriched water sample to obtain a water sample to be analyzed; the detection unit receives the water sample to be analyzed and carries out thallium analysis detection on the water sample to be analyzed. Wherein the pH adjusting unit comprises a pH adjusting column, and the pH adjusting column comprises hydroxyl type resin and is used for exchanging anions in the enriched water sample and carrying out neutralization reaction with H < + > in the enriched water sample so as to reduce the acidity of the enriched water sample, so that the compatibility contradiction between the solid-phase extraction elution acidity and the liquid anode glow discharge spectrum sample introduction acidity in the prior art is overcome; meanwhile, interference cations are prevented from being introduced, and high-sensitivity analysis on trace thallium in water is realized.

The application discloses a kind of ammonium sulfate production system mother liquor acidity control method, comprising: (1) setting normal mother liquor acidity, and the total volume of current mother liquor and the acidity of current mother liquor are obtained by on-line detection;(2) according to the volume of coal gas entering saturator in unit time and the ammonia content of coal gas inlet and outlet, the amount of sulfuric acid consumed in unit time is calculated according to the reaction formula;(3) when the acidity is lower than the normal mother liquor acidity, the volume of sulfuric acid to be added is calculated according to the amount of acid consumed and the amount of acid required to adjust the acidity, when the acidity is higher than the normal mother liquor acidity, the volume of water required to adjust to the normal mother liquor acidity is calculated;(4) when adding concentrated sulfuric acid, first add acid quickly with the target amount of sulfuric acid required to adjust to the normal mother liquor acidity, then add acid uniformly with the target amount of sulfuric acid consumed in unit time, and when adding water, add water quickly.The application realizes automatic adjustment of acidity, improves the level of automation, and is more conducive to improving the quality of ammonium sulfate crystals.

The invention discloses a silver nano-cluster and a preparation method and application thereof, belongs to the technical field of metal cluster materials, and aims to synthesize Ag NCs by taking PEI as a template and ascorbic acid as a reducing agent. The invention also discloses an application of the silver nanocluster in pH sensing. As the pH sensor, the Ag NCs provided by the invention can show obvious fluorescence intensity and absorbance changes along with the change of acidity, so that the Ag NCs can combine the advantages of high sensitivity of fluorescence detection and simplicity, convenience, rapidness and the like of a colorimetric method, and has more obvious advantages compared with other nanoscale pH sensors.

1. Name of the product in this design: Laboratory pH Meter (XS-3EB). 2. Application of this design: To measure the acidity or alkalinity of solutions in laboratories, near production lines, or on-site. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The present invention provides a glass composition that yields glass that is poorly soluble in acidic and neutral environments, even in environments where the acidity changes between neutral and acidic ranges. [Solution] The glass composition contains gallium and phosphorus, at least one selected from alkali metals, calcium, and strontium, and contains aluminum in an oxide equivalent of 0% to 3.8% by mass.

The present application belongs to the technical field of germanium material preparation, and particularly relates to a method for recovering germanium in neutralized residue containing germanium by slow distillation under low acidity with surfactant reinforcement, and specifically comprises the following steps: after waste acid is neutralized with lime after first distillation, the cake is formed by pressure filtration, and the neutralized residue is formed; the neutralized residue with a germanium content higher than 0.4% is screened for standby; manganese dioxide is added according to 3 times to 5 times of the total mass of germanium metal in the neutralized residue obtained by calculation, industrial hydrochloric acid is added according to a mass-volume ratio of the neutralized residue and hydrochloric acid of 1:1 to 3, and the reaction is preheated at low temperature for 1.5 hours to 2.5 hours; the temperature of the distillation reaction kettle is controlled at 45 DEG C to 65 DEG C, the pressure in the reaction kettle is controlled between 10 kpa to 15 kpa, etc.; the germanium in the neutralized residue is separated and extracted by slow distillation under low acidity in the second distillation, and the direct recovery rate can reach 90%, and the recovery rate can reach 93%.