21 results about "Acid digestion" patented technology

The invention belongs to the technical field of soil and sediment detection, and particularly relates to a method for measuring the content of a tin element in soil and sediment, which comprises the following steps: S1, sample treatment; the method comprises the following steps: weighing a soil or sediment sample, adding an acid solution and ultrapure water, carrying out gradient heating digestion, and fixing the volume with acid after digestion to obtain a test solution; the method is different from a conventional four-acid digestion method, and digesting is carried out by using a diacid digestion method of nitric acid and hydrofluoric acid and a full-automatic graphite digestion method; s2, tin content determination: taking the test sample solution, injecting the test sample solution into an inductively coupled plasma mass spectrometer to obtain test data, and calculating the content of the tin element in the test sample solution according to the test data. The tin element is measured by combining the inductively coupled plasma mass spectrometer, the detection mode is matched with an optimized gradient heating and diacid full-automatic digestion method, the accuracy and reliability of a detection result can be guaranteed, and the method is suitable for accurate analysis of the tin element in soil and sediments.

The invention relates to a sample pretreatment method for chromite microelement analysis. The method comprises the following steps: firstly, treating a sample to specific particle size distribution (Dv (50) lt, 5 [mu] m, Dv (90) lt, 20 [mu] m) through physical accurate grinding, and then adopting an improved two-step acid dissolution and digestion process: firstly, destroying main crystal lattices of minerals by using mixed acid, then, carrying out targeted dissolution on a residual insoluble phase by using aqua regia, and finally, carrying out chlorine removal treatment to obtain a solution to be detected. Through the synergistic effect of physical accurate grinding and secondary acid dissolution, almost complete decomposition of chromite is achieved, especially the extraction efficiency of key indissolvable elements such as Sc and Zn is improved by 20% or above, the accuracy and precision of ICP-MS analysis results are remarkably improved, and the problem that microelement measured value systematicness is low due to incomplete dissolution in a traditional method is solved.

The invention discloses a method and a device for testing a magnetic substance of a battery negative electrode material, and the method comprises the following steps: dispersing the battery negative electrode material in absolute ethyl alcohol to form a mixed solution; performing ultrasonic pretreatment on the mixed solution to desorb the magnetic substance from the battery negative electrode material to form a mixed solution after ultrasonic treatment; adsorbing a magnetic substance desorbed from a battery negative electrode material through a magnetic rod coated with polytetrafluoroethylene; after the adsorption is finished, cleaning the magnetic bar which adsorbs the magnetic substance and is coated with polytetrafluoroethylene, and carrying out acid digestion treatment to obtain a digestion solution; based on the digestion solution, the content of the magnetic substance is tested through an inductively coupled plasma instrument, and testing of the magnetic substance of the battery negative electrode material is completed. The problem of incomplete adsorption caused by retention of magnetic substances in holes due to the porosity of the negative electrode material can be improved, so that the desorbed magnetic substances are captured immediately; the method can be compatible with conventional equipment in a laboratory, is economical and simple and convenient to operate, and improves the accuracy and reliability of the test to a greater extent.

The application provides a high-temperature acidolysis device and method for uranium-containing polymetallic silicate ore, and relates to the technical field of hydrometallurgy. The device is used for high-temperature acidolysis of uranium-containing polymetallic silicate ore, the function structure of a slurry preparation tank is designed, and material is added in batches in sections, so that the risk of slurry tank overflow is reduced, and the time for slurry preparation is shortened; the reaction heat and dilution heat are used to make the material mature in the stirring tank, so that the energy consumption is reduced, and the reaction time in the subsequent high-temperature acidolysis process is shortened. The solidification of the slurry and the high-temperature acidolysis equipment are modularized and connected in series, and are carried out in the paddle stirring equipment, so that the rapid solidification of the slurry and the fine control of the high-temperature acidolysis process are realized, the technical problems of material caking and scarring in the high-temperature acidolysis are effectively solved, the energy consumption is reduced, the amount of waste gas generated in the acidolysis process is reduced, and the equipment floor area is saved.

The invention provides a preparation method of a red-mud-based photoelectrode and application of the red-mud-based photoelectrode in photoelectrocatalysis, and belongs to the technical field of solid waste resource utilization and photoelectrocatalysis. Industrial solid waste red mud is used as a raw material, a precursor solution is obtained through acid digestion treatment, a solution system is optimized by regulating and controlling the pH value, a thin film grows on a substrate material through the hydrothermal deposition technology, and finally the red mud-based photoelectrode is obtained through high-temperature calcination. The method adopted by the invention is simple and convenient in process and low in raw material cost, iron-based components such as Fe2O3 rich in the red mud can be efficiently activated, and in-situ doping and structure regulation and control of various metal elements are realized. The prepared red mud-based photoelectrode can be applied to the field of photoelectrocatalysis, including hydrogen production through water decomposition, biomass conversion, solid waste recycling and the like. According to the method, waste is treated with waste as the core, a new way is opened up for comprehensive utilization of the red mud solid waste, and the method has good application potential in the fields of environment and energy.

The invention discloses an electrochemical sensor detection device for heavy metal residues in star anise, and relates to the technical field of star anise detection.The electrochemical sensor detection device comprises an electrochemical sensor detection device body, T-shaped grooves are formed in the positions, close to the left side and the right side, of the rear side of the electrochemical sensor detection device body, and T-shaped blocks are movably connected into the T-shaped grooves; through mutual cooperation of an electrochemical sensor detection device body, a motor, a safe acid adding bottle, a connecting cylinder and other structures, a small amount of star anise can be placed in the connecting cylinder, the motor cooperates with a crushing rod to crush the star anise, and then one-time use amount of acid in the safe acid adding bottle is poured into the connecting cylinder; according to the invention, star anise powder is subjected to acid digestion, then ultrapure water is added, a filter disc filters liquid in a connecting cylinder, then the connecting cylinder is moved, a liquid sample flows into an electrochemical sensor detection device body, and the electrochemical sensor detection device body detects the liquid sample.

Improved methods for the removal of heavy metals, in particular cadmium, from an aqueous phosphoric acid containing composition, using an organothiophosphorous heavy metal precipitating agent to said composition, wherein the reaction between the heavy metals, in particular cadmium, and the organothiophosphorous precipitating agent is performed at a pH ranging between 1.6 and 2.0 measured after a 13-fold dilution by volume. Advantageously, an ionic polymer, particularly a cationic and / or an anionic poly(meth)acrylamide copolymer may be used to promote heavy metal precipitation and / or to facilitate the removal of the precipitates from the composition. More in particular, the phosphoric acid containing composition is obtained by the acid digestion of phosphate rock, preferably by nitric acid, sulfuric acid, or a combination thereof.

The present disclosure provides improved methods for the removal of heavy metals, in particular cadmium, from an aqueous phosphoric acid containing composition, wherein an ionic polymeric flocculating agent is added to a phosphoric acid containing composition subsequent to the addition of an organothiophosphorous heavy metal precipitating agent to said composition, particularly under gentle mixing conditions, such as between 100 and 300 rpm. The flocculating agent promotes the formation of agglomerates of the heavy metal containing precipitate, thus facilitating their removal from the composition. More in particular, the phosphoric acid containing composition is obtained by the acid digestion of phosphate rock, preferably by nitric acid, sulfuric acid, or a combination thereof.

Improved methods for the removal of heavy metals, in particular cadmium, from an aqueous phosphoric acid containing composition, wherein an organothiophosphorous heavy metal precipitating agent and an ionic polymeric surfactant, particularly a cationic polyacrylamide copolymer surfactant, are both added to a phosphoric acid containing composition, particularly under vigorous mixing conditions, such as between 500 and 700 rpm. The ionic polymeric surfactant promotes the precipitation of the heavy metals. More in particular, the phosphoric acid containing composition is obtained by the acid digestion of phosphate rock, preferably by nitric acid, sulfuric acid, or a combination thereof.

The invention discloses a method for detecting the content of a zirconium element in high-purity quartz sand, which comprises the following steps: heating and digesting the high-purity quartz sand by using an acid digestion solution in a closed environment, and evaporating a solvent to dryness after the digestion is completed to obtain a residue; transferring the residues into a heat-resistant container by using nitric acid, evaporating the solvent to dryness, then adding strong base, and heating to carry out alkali dissolution reaction; the alkali dissolution reaction comprises the following steps: heating to 200-300 DEG C, preserving heat for a period of time, heating to 550-950 DEG C, and preserving heat for a period of time; cooling after the alkali dissolution reaction is finished, dissolving an alkali dissolution reaction product with nitric acid, and fixing the volume with pure water to obtain a sample solution; preparing a standard impurity solution and a blank sample solution; the sample solution, the standard impurity solution and the blank sample solution are tested and analyzed through ICP-OES or ICP-MS, and the content of the zirconium element in the high-purity quartz sand is obtained.

The application discloses a kind of based on organic matter interference evaluation cadmium isotope standard substance stability verification method, belongs to environmental monitoring and geology reference material analysis technical field, the method first from the mixed to be evaluated Cd standard reference material large sample Randomly equal amount takes two samples;Two samples are respectively subjected to acid digestion and Cd separation and purification, then MC-ICP-MS measurement is carried out, obtains the δ 114 / 110 Cd value of each sample;Finally, the difference of the δ 114 / 110 Cd value of two samples is calculated and compared with threshold value to judge the homogeneity and stability of the Cd isotope composition of the standard substance, and the effectiveness of the method is verified by the fact that the measurement results of the control sample are within the known demonstration interval. The verification method directly separates the sample when taking the solid powder sample, classifies and evaluates it based on its inherent physical and chemical properties, and provides a reliable reference standard substance screening method for Cd isotope research of environmental samples.

The invention discloses a method for detecting ruthenium and ruthenium oxide in a high-level liquid waste glass solidified body, and belongs to the technical field of glass solidified body detection. The method comprises the following steps: firstly, mixing basic glass powder with simple substance ruthenium and ruthenium oxide to prepare a series of standard samples, then carrying out acid digestion and then filtering to remove high-content components such as substrate silicon dioxide and sodium oxide, so that the simple substance ruthenium and the ruthenium oxide are left on a filter membrane; the method comprises the following steps: measuring diffraction spectrograms of ruthenium and ruthenium oxide on a filter membrane by adopting an X-ray diffractometer, drawing a standard working curve according to the integral intensity of a main strong diffraction peak of elemental ruthenium and the integral intensity of a secondary strong diffraction peak of ruthenium oxide, and then carrying out the same treatment on a to-be-measured glass solidified body sample to obtain the corresponding integral intensity. The method disclosed by the invention is simple, the synchronous distinguishing detection of the simple substance ruthenium and the ruthenium oxide can be realized, and the detection precision is high.

The invention discloses a pretreatment method for detecting metal impurities in an electronic-grade triethyl phosphate precursor. The pretreatment method comprises a sample pretreatment and sample preparation stage, a vacuum volatilization stage, a concentrated acid digestion stage, a dilution and constant volume stage and a computer testing stage. According to the method, the boiling point of the sample is reduced by adopting a negative pressure (vacuumizing) condition along with volatilization (heating by a heating plate) mode, so that the purpose of complete volatilization is achieved, the influence of overhigh concentration of a sample substrate on other metal ions is reduced, and the problems of difficult volatilization and unstable process in pretreatment of metal ions with high boiling point and high substrate substances are solved.

The invention discloses a method for evaluating acidolysis settling performance of titanium concentrate. The method comprises the following steps: carrying out ball milling on the titanium concentrate with first mass to obtain titanium concentrate powder with second mass; sieving the second mass of titanium concentrate powder to obtain third mass of titanium concentrate powder; the titanium concentrate powder with the third mass is dissolved in water, and mineral powder with the fourth mass floating on the water surface is collected; the scheme provided by the invention is suitable for the field of sulfuric acid process titanium dioxide production, and simple and rapid experiments on the titanium concentrate are realized, so that the quality of the titanium concentrate in the sedimentation process of sulfuric acid process titanium dioxide production is predicted; and concentrated sulfuric acid does not need to be used for complete titanium concentrate acidolysis, leaching and flocculating settling experiments, so that accurate raw material entering quality control is realized, the production risk is avoided from the source, the production stability is improved, and the comprehensive cost is reduced.

A method for producing high purity carbon nanotube (CNT) materials, in some cases such that they contain no more than 10,000 ppm total residual catalyst and residual metal, and in some cases no more than 1,000 ppm of such contaminants. The method includes providing starting CNT material from a CNT synthesis process wherein CNTs are grown on supported active metal catalyst, performing a thermal oxidation treatment on the starting CNT material in a furnace under a controlled atmosphere in a temperature range and for at least a minimum time, to produce an oxidized CNT material wherein metals are oxidized, and performing an acid digestion treatment on the oxidized CNT material using a defined acid and for at least a minimum time, to dissolve oxidized metals and produce the high purity CNT material.

This invention discloses a method for determining the phosphate oxygen isotopes of a single dentomorph based on ion chromatography-electrostatic orbital trap mass spectrometry, belonging to the field of isotope geochemical analysis technology. The method includes: acid digestion step; lyophilization step; reconstitution step; ion chromatography separation and fraction collection step; mass spectrometry analysis step: acquiring the mass spectrometric signals of the target fragment ions; isotope ratio calculation step: calculating the oxygen isotope shift of the sample relative to the reference solution; and calibration step: establishing a calibration curve using multiple known phosphate reference materials to obtain the phosphate oxygen isotope composition of the sample. This invention simultaneously solves three technical bottlenecks in existing thermal conversion elemental analysis-isotope ratio mass spectrometry methods: high sample consumption and cumbersome procedures prone to fractionation; secondary ion mass spectrometry methods: mixed signals and inability to distinguish different oxygen-containing components; and pure solution electrostatic orbital trap mass spectrometry methods: lack of solid sample pretreatment support.

Improved methods for the removal of heavy metals, in particular cadmium, from an aqueous phosphoric acid containing composition, wherein an ionic polymeric flocculating agent is added to a phosphoric acid containing composition subsequent to the addition of an organothiophosphorous heavy metal precipitating agent to said composition, particularly under gentle mixing conditions, such as between 100 and 300 rpm. The flocculating agent promotes the formation of agglomerates of the heavy metal containing precipitate, thus facilitating their removal from the composition. More in particular, the phosphoric acid containing composition is obtained by the acid digestion of phosphate rock, preferably by nitric acid, sulfuric acid, or a combination thereof.

1. Name of the designed product: Digestion tube. 2. Use of the designed product: For acid digestion of samples. 3. Design points of the designed product: In shape. 4. Picture or photo that best shows the design points: Perspective view.

The invention discloses an integrated cartilage decellularization kit and a decellularization method thereof, and belongs to the technical field of biomedicine. The kit comprises an independently packaged ready-to-use tissue lysis buffer solution and nucleic acid digestive enzyme dry powder mixture, the pH value of the ready-to-use tissue lysis buffer solution is 7.4-7.6, and every 100 mL of the ready-to-use tissue lysis buffer solution contains 0.9 g of sodium chloride, 0.05-0.2 g of sodium deoxycholate monohydrate, 0.05-0.2 g of calcium chloride dihydrate, 0.05-0.2 g of magnesium chloride hexahydrate and 0.4-0.6 mL of a surfactant. The nucleic acid digestive enzyme dry powder mixture is a mixture of DNase I dry powder and RNase A dry powder, and the mass ratio of the DNase I dry powder to the RNase A dry powder is 1: (0.4-0.6). The invention further discloses a decellularization method adopting the integrated cartilage decellularization kit. According to the invention, the decellularized cartilage scaffold which has low immunogenicity and highly retains natural extracellular matrix structure and biochemical composition can be stably prepared.

The invention discloses a compound enzyme digestion method for enriching methylated DNA fragments. The compound enzyme digestion method for enriching methylated DNA fragments comprises the step of simultaneously carrying out methylated sensitive restriction enzyme digestion and single-stranded nucleic acid digestion in one reaction. According to the compound enzyme digestion method for enriching methylated DNA fragments, provided by the invention, single-stranded nuclease is introduced, so that methylated sensitive restriction enzyme digestion and single-stranded nucleic acid digestion are simultaneously carried out in one reaction, the interference of nucleic acid fragmentation on MSRE is effectively eliminated, and the accuracy of methylation detection based on MSRE is improved.

The invention relates to the technical field of chemical analysis and detection, and discloses a multi-element synchronous detection method for a regenerated calcium fluoride sludge calcined product, which comprises the following steps: taking a regenerated calcium fluoride sludge calcined product sample, adding an alkaline reagent, an oxidation reagent and a phosphorus-sulfur anchoring agent into the regenerated calcium fluoride sludge calcined product sample, and performing ultrasonic treatment to obtain a sample; performing first-stage heating to obtain a first-stage product; adding an F-complexing agent and an acid digestion reagent into the product in the stage I, and carrying out second-stage heating to obtain a digestion solution; and fixing the volume of the digestion solution, and determining the concentrations of at least two target elements selected from silicon, phosphorus, sulfur, calcium, lead and cadmium in the digestion solution by adopting an inductively coupled plasma emission spectrometer. According to the method, phosphorus and sulfur elements are converted into thermally stable solid-phase salts through a first-stage heating procedure, so that the defect that the recovery rate is low due to the fact that phosphorus and sulfur components are easily volatilized and lost at an acidic high temperature is overcome.