35 results about "Potentiometric titration" patented technology

The invention discloses a method for determining the content of hydrogen ions in a chloroplatinic acid solution, and belongs to the technical field of analytical testing. In order to solve the problems that the chloroplatinic acid solution is yellow after being diluted and the manual titration end point is difficult to judge, a potentiometric titration method is adopted, and the end point is determined by measuring electrode potential mutation without depending on indicator color change. The method comprises the steps of test condition preparation, burette calibration, standard solution preparation and calibration, sample treatment and titration, result calculation and the like, a full-automatic potentiometric titrator is selected, the titration volume is controlled within the range of 10-15 mL, and a sodium hydroxide standard solution is used for sample titration after calibration. The relative standard deviation of the determination result is less than 0.5%, the adding standard recovery rate is between 96.3% and 103.1%, and the method has the characteristics of high analysis speed, high accuracy and good stability, is suitable for accurate detection of hydrogen ions in chloroplatinic acid production and quality inspection, and effectively solves the defects of the traditional method.

The utility model relates to the technical field of potentiometric titration instruments, in particular to a potentiometric titration instrument with a burette monitoring device, which comprises a titration instrument body, a titration table is arranged at the upper end of one side of the titration instrument body, a placement groove is arranged in the middle of the right side of the titration table, and a clamping mechanism is arranged between the placement groove and the titration table; the sleeve is movably mounted in the middle of the left side of the titration table. During use, as the two sides of the first rack are meshed with the driving gear and the driven gear respectively, the driven gear is driven to rotate and controls the second rack on the other side to move in the opposite direction, the push rod is pushed through the connecting pieces on the two sides, and the push rod controls the first clamping plate to tighten the spiral spring; after being compressed, the spiral spring drives the second clamping plate to adaptively clamp the titration container, so that the titration container can be quickly clamped, and after an experiment is completed, the sleeve is reversed to reset the spiral spring, so that the second clamping plate can be loosened, and the operation is convenient during use.

The invention relates to the field of chemical analysis automation equipment, and discloses an automatic potentiometric titration method which comprises the following steps: before a titration task is started, executing adaptive cleaning and collecting residual spectrum fingerprints of a system; calibrating a titration prediction model in real time by using the fingerprint; performing predictive titration to obtain complete titration data; after the titration is finished, carrying out multi-dimensional analysis on the whole process data, and quantitatively evaluating the pollution risk and the data quality; and finally, dynamically adjusting the cleaning strategy of the next task according to the evaluation result, and adaptively updating the prediction model according to the prediction deviation of the titration. By establishing a closed-loop intelligent working process of cleaning, diagnosis, feedback and learning, the state of the system can be sensed in real time, a cleaning strategy and a prediction model can be dynamically adjusted, the cleaning effect is ensured, self-optimization of the titration process is also realized, the long-term analysis accuracy and the intelligent level of the automatic titration system are improved, and the working efficiency is improved. And the dependence on manual intervention and troubleshooting is reduced.

The invention discloses an analysis method for determining the content of water-soluble chlorine in basic cupric carbonate. Compared with the prior art, the method has the advantages that by optimizing sample treatment and determination conditions, the determination accuracy and precision are remarkably improved, and meanwhile, the analysis time is shortened. Specifically, a set of sample pretreatment process is customized according to different contents of water-soluble chlorine in a sample, and rapid and accurate chlorine content determination is realized through an improved potentiometric titration technology. According to the method, the detection efficiency is improved, and the reliability of the result is ensured by reducing personal errors. In addition, the analysis speed of the method is 1.5 times higher than that of a traditional method, the accuracy is improved by 30%, and the precision error range is reduced to 5%.

The invention discloses a method for determining the content of sulfate radicals in a water sample. According to the method, a calcium ion selective electrode is selected as an indicator electrode through a full-automatic potentiometric titration method, the amount of EDTA consumed by Ca < 2 + > and Mg < 2 + > in a to-be-detected water sample and the amount of EDTA consumed by Ba < 2 + > in a blank solution are respectively measured by using an EDTA standard solution, and then the previously titrated blank solution containing Ba < 2 + > which is excessive relative to the content of SO4 < 2-> in the to-be-detected water sample is added into the to-be-detected water sample; and measuring the content of excessive Ba < 2 + > by using an EDTA standard solution, and calculating to obtain the content of SO4 < 2-> in the water sample to be measured. The method is suitable for measuring the content of sulfate radicals in a water sample with high content of calcium, magnesium ions and sulfate radicals, and has the advantages of simple detection method, low cost and high practical value.

The invention relates to the technical field of air detection, and particularly discloses a method for measuring formaldehyde content in indoor air, which is used for measuring indoor formaldehyde gas by potentiometric titration and comprises the following steps: firstly, preparing a K2Cr2O7 standard solution, a Fe < 2 + > standard solution and a formaldehyde standard solution; secondly, taking a K2Cr2O7 standard solution as an absorption liquid of formaldehyde gas, adding sulfuric acid and distilled water, heating in a water bath, transferring into a gas sampler, and sampling air to obtain a sample collection liquid; and placing the sample collection solution in a water bath kettle, continuously heating, titrating the excess K2Cr2O7 and formaldehyde blank sample by using an automatic potentiometric titrator by using a Fe < 2 + > standard solution as a titrating solution, and calculating the content of formaldehyde in the air. The method disclosed by the invention is simple to operate and accurate in determination, the reaction speed can be increased, the reaction degree can be improved, the lowest detection limit can reach 0.006 mg / m < 3 >, and the method can be used for determining the indoor formaldehyde content. The problems that in the prior art, operation is tedious, the duration time is long, and the detection limit is too high are solved.

The present invention provides a method for detecting the acid value in a low concentration in a photovoltaic adhesive film. The method includes the following steps: preparation of a sample to be tested; testing stage: first, the content and types of volatile acids of the sample to be tested are detected by headspace gas chromatography-mass spectrometry (HS-GC-MS), then the sample after headspace treatment is recovered and placed in a solvent, and swelling extraction is carried out by water bath ultrasonic treatment to obtain an extraction solution. After titration testing with an automatic potentiometric titrator in combination with an indicator, the acid value C is obtained; analysis of the test results. For the first time, it is proposed to combine headspace gas chromatography-mass spectrometry (HS-GC-MS) with full-automatic potentiometric titration to detect the acid value in the adhesive film. The combination of back titration and indicator method is used to improve the accuracy of detection, and for the first time, it is innovatively proposed to simulate the aging environment in a headspace vial to more accurately and comprehensively detect the acid value of the photovoltaic adhesive film.

The invention belongs to the field of metal ion concentration detection, and particularly relates to a method for detecting the concentration of vanadium ions in a vanadium battery negative electrode electrolyte through two-step potentiometric titration. Aiming at the problems of inaccurate measurement result, large error and complicated operation of the existing vanadium battery negative electrode electrolyte, the vanadium ion concentration in the vanadium battery negative electrode electrolyte is detected by adopting two steps of potentiometric titration, the first titer is that the negative electrode electrolyte is added into a mixed acid solution containing excessive pentavalent vanadium and sulfur and phosphorus in an open system, and the second titer is equal to the first titer; 2-valent and 3-valent vanadium ions in the solution are all oxidized into 4-valent vanadium ions by pentavalent vanadium ions, meanwhile, part of pentavalent vanadium ions are reduced into 4-valent vanadium ions, and then potassium permanganate is used for titration of the concentration of the 4-valent vanadium ions in the solution so as to solve the problem of exposure oxidation of the 2-valent vanadium ions; in the second step of titration, potassium permanganate is directly used for titration of vanadium ion concentration in the negative electrode electrolyte. Results prove that the method is small in detection result deviation, high in precision and accuracy, portable in carried instrument and suitable for real-time monitoring of the energy storage power station.

The application discloses a kind of residual alkali detection methods in sodium ion layered oxide positive material, comprising the following steps: step 1, dispersing agent is added to sodium ion layered oxide positive material, stirring, extraction, suction filtration, and filtrate is collected;The dispersing agent is combined by polar organic reagent and water;Step 2, the pH value of filtrate is measured using potentiometric titration method, and the residual alkali in sodium ion layered oxide positive material is calculated.The application has the following beneficial effects: by adding an appropriate amount of polar organic reagent on the basis of using water as dispersant, the generation of NaOH in the material during testing and its influence on testing are inhibited, the testing interference caused by excessive organic solvent is avoided, the stability of the material during potentiometric titration is improved, and the sodium carbonate content detection result is more accurate and stable.

The invention relates to the technical field of solution concentration analysis, in particular to a method for measuring the concentration of each component of a hydrofluoric acid and fluosilicic acid binary system, which comprises the following steps: step 1, weighing a certain amount of mixed acid solution, dispersing in a solvent, taking alkali liquor as a titrant, and measuring the concentration of each component of the hydrofluoric acid and fluosilicic acid binary system; the volume # imgabs0 # of alkali liquor consumed accumulatively at a first jump point of the mixed acid solution and the volume # imgabs1 # of alkali liquor consumed accumulatively at a second jump point of the mixed acid solution are measured through potentiometric titration, and the first jump point corresponds to a neutralization reaction of # imgabs3 # in # imgabs2 #; the second jump point corresponds to a neutralization reaction of # imgabs 5 # in # imgabs 4 #; 2, according to the mass of the weighed mixed acid, the mass fraction of the # imgabs8 # and the mass fraction of the # imgabs9 #, the mass fraction of the # imgabs8 # and the mass fraction of the # imgabs9 # are calculated;

The invention discloses an automatic potentiometric titration detection method for analyzing the content of sodium carbonate in alkali powder. The reaction principle in the process of detecting the content of sodium carbonate in the alkali powder is an acid-base neutralization reaction, the pH value in the reaction cup can change along with the continuous reaction process, the corresponding pH value is identified through the potential change of the electrode on the automatic potentiometric titrator to indicate the titration end point, and the content of sodium carbonate in the alkali powder is detected and analyzed. According to the detection result, the poor accuracy of the manual titration detection result is eliminated, the operation is simple, the reagent consumption is low, the detection efficiency is high, and the detection analysis of the effective calcium oxide content in the lime can be accurately and quickly realized.

The invention discloses a method for measuring the content of cyanide in sodium nitroprusside by potentiometric titration, which comprises the following steps: taking a cyanide ion selective electrode as an indicator electrode, adding disodium ethylene diamine tetraacetate into a solution to be measured, and measuring the content of cyanide in sodium nitroprusside under an alkaline condition. The method is easy to operate, high in safety, high in sensitivity, good in precision and high in accuracy, and the content of cyanide in sodium nitroprusside and related preparations of sodium nitroprusside can be rapidly and accurately measured.

The invention relates to a potentiometric titration method for measuring the concentration of divalent silver ions, which comprises the following steps: installing an electrode in a container, and adding sample liquid into the container to submerge the electrode; a burette is installed above the container, a titrating solution is put into the burette, and the titrating solution is cerous nitrate; dropwise adding the titration solution into the sample liquid for multiple times, determining the titration amount of each dropwise adding and the electrode potential in the corresponding titration process, waiting for a first preset time after each titration, then reading the electrode potential, waiting for a second preset time after reading the electrode potential, and then carrying out next titration; based on the titer and the electrode potential of each time, the change rate of the electrode potential along with the titer is obtained; positioning a critical point of the electrode potential based on the change rate, and determining a target titer when the electrode potential reaches the critical point; and determining the concentration of the divalent silver ions based on the target titer. The technical effects that the detection result is more accurate, the automation degree is improved, and the risk of the reagent is reduced are achieved.

The invention relates to the technical field of sodium aluminate solution analysis, and provides a sodium aluminate solution on-line analysis system and method.The sodium aluminate solution on-line analysis system comprises an on-line sampling module used for automatically collecting a sodium aluminate solution sample from a production pipeline and conducting pretreatment on the sodium aluminate solution sample, and filtering suspended particles and conducting automatic dilution according to the concentration range; the multi-channel analysis module integrates a near infrared spectrum analysis unit, a potentiometric titration analysis unit and a conductivity / TOC sensor unit and is used for synchronously detecting the contents of aluminum oxide, total alkali, caustic alkali and carbon alkali in the sodium aluminate solution; and the intelligent control module is based on a PLC (Programmable Logic Controller) or an industrial computer and is used for controlling an analysis process and optimizing detection parameters. Through synchronous operation of the multi-channel module, the traditional manual detection period of 2-6 hours is greatly shortened to 20-40 minutes, and the real-time performance is improved by matching with the full-process automatic design of automatic sampling, filtering and diluting; meanwhile, due to cooperative application of technologies such as near infrared spectrum and potentiometric titration, the detection precision reaches + / -0.5%.

According to the boron trifluoride gas content on-line detection system device for boron isotope separation and the on-line detection method, boron trifluoride gas in the process is absorbed and converted into boric acid on line, and then the content of the boric acid is detected on line by utilizing a potentiometric titration method; the total amount of the gas after boron trifluoride exchange rectification in the process is obtained through conversion; compared with the prior art, the on-line detection system device and the on-line detection method have the advantages that leakage of toxic gas can be effectively avoided, environmental water is prevented from entering a reaction system due to sampling, adverse effects of temperature and pressure fluctuation on product quality can be reduced, and the device is prevented from being eroded by a byproduct hydrogen fluoride.

The invention relates to the technical field of potentiometric titration, in particular to a multi-station automatic potentiometric titration analysis system, which is used for solving the problem of poor glass beaker positioning effect in the prior art. The system comprises a positioning mechanism, a clamping mechanism and a position correcting mechanism, the clamping mechanism comprises a first clamping plate and a second clamping plate which symmetrically slide on the upper portion of a mounting base, and the first clamping plate and the second clamping plate get close to each other to push a positioning rod to synchronously get close to a glass beaker; the rotating shaft is provided with first teeth in vertical one-to-one correspondence with the positioning rods, a rectangular rod is slidably connected into the mounting seat, the rectangular rod is provided with second teeth, the rotating shaft has a first state and a second state, when the rotating shaft is in the first state, the second teeth can be meshed with the first teeth, and when the rotating shaft is in the second state, the second teeth can be meshed with the second teeth. The second teeth are not engaged with the first teeth; the system can stably clamp the glass beaker.

This invention belongs to the field of detection technology, specifically disclosing a method and system for detecting chloride ions in high-concentration samples used in the salt-making industry. The detection method includes the following steps: (1) cyclically taking samples from the process pipeline to ensure real-time sample availability; (2) diluting the sample to ensure that the concentration of the sample falls within the optimal detection range; (3) inputting the diluted sample into the titration system, performing titration using potentiometric titration, outputting the first derivative DE / DV in real time, and using a nonlinear normalization function to normalize the original DE / DV sequence to obtain S. norm Value, according to S norm Adjust the speed of the titration pump, S norm The point corresponding to the maximum value is the titration endpoint. The titration volume V2 of the silver nitrate standard solution at this point is recorded, and the chloride ion concentration in the pipeline sample is calculated. This invention stably maps the wide-range fluctuating DE / DV signal to a fixed interval, solving the core problem of inaccurate endpoint determination and ensuring the accuracy and reliability of the detection results.

The utility model belongs to the technical field of waste acid treatment, and particularly relates to a waste acid concentration detection device which comprises an electromagnetic stirrer, a base and an automatic potentiometric titrator are respectively arranged on the side edge of the electromagnetic stirrer, a stirring cup is arranged on the electromagnetic stirrer, and a connecting port and a wire are arranged on the automatic potentiometric titrator. A reference electrode and an indicator electrode are arranged on the wire, a first supporting rod and a second supporting rod are arranged on the base, a fixing sleeve and a connecting plate are arranged on the first supporting rod, a connecting rod is arranged on the fixing sleeve, a bearing ring is arranged on the connecting rod, a bearing rod is arranged on the connecting plate, a limiting ring and a supporting ring are arranged on the bearing rod, and the limiting ring and the supporting ring are arranged on the supporting rod. A dropper is arranged in the supporting ring, and an electromagnetic valve is arranged on the dropper. According to the utility model, a manual titration method is replaced by a potentiometric titration method, a titration end point can be automatically found out in a titration process by using the automatic potentiometric titrator, and finally, the dropping amount of a medicament is controlled through the electromagnetic valve, so that errors caused by manual operation are avoided.

The invention relates to the technical field of solution concentration analysis, in particular to a method for measuring the concentration of each component in hydrofluoric acid, ammonium fluoride and acetic acid mixed acid liquor, which comprises the following steps: step 1, weighing a certain amount of mixed acid liquor, dispersing the mixed acid liquor in a solvent, and taking alkali liquor as a titrant, determining the volume # imgabs0 # of alkali liquor accumulated and consumed by a first jump point and the volume # imgabs1 # of alkali liquor accumulated and consumed by a second jump point of the mixed acid solution through potentiometric titration; step 2, weighing a certain amount of the mixed acid solution, dispersing the mixed acid solution in a solvent, and titrating the solution to be neutral through a potentiometric titration method by taking alkali liquor as a titrant; then, a fluorine ion electrode is adopted, # imgabs2 # is used as a titrant for continuous titration, and the consumption of # imgabs3 # is the consumption of # imgabs4 #; 3, according to the mass of the weighed mixed acid and the concentration of the # imgabs 5 #, the concentration of the # imgabs 6 #, the concentration of the # imgabs 7 # and the concentration of the titrant, the mass fraction of the # imgabs 8 #, the mass fraction of the # imgabs 9 # and the mass fraction of the # imgabs 10 # are calculated. The method can accurately measure the content of each component in an unconventional mixed acid liquid system of hydrofluoric acid, ammonium fluoride and acetic acid.

The utility model discloses automatic potentiometric titration detection equipment for marinated products, and relates to the field of titration detection.The automatic potentiometric titration detection equipment comprises a main machine, an operation face is installed on the main machine, a burette fixing base is installed on the main machine, a lower stirrer is installed on the main machine, and an electrode telescopic support is arranged on one side of the lower stirrer; a fine adjustment mechanism is arranged on the electrode telescopic support, and a rapid fixing mechanism is arranged between the electrode telescopic support and the main machine. The electrode telescopic support is used for driving the electrode to enter a solution to be measured, then the fine adjustment mechanism is used for fine adjustment to the accurate height, titration is started, and the reading of the solution measured by the electrode is read in time on the operation surface in the titration process. Therefore, the possibility that a worker needs to repeatedly adjust the electrode telescopic support to reach a proper height, and time and labor are wasted can be reduced, and meanwhile, the height of the electrode in a solution to be detected is more accurate.

This invention provides an automated potentiometric titration method for determining the platinum content in platinum jewelry, belonging to the field of precious metal analysis and detection technology. The method mainly includes: dissolving the platinum jewelry sample in aqua regia and using a separating reagent to precipitate and separate interfering precious metals such as palladium, gold, and silver. Subsequently, the sample is passed through a strongly basic anion exchange resin column, where platinum is selectively adsorbed as chloroplatinate complex anions to obtain a purified platinum solution. The platinum content is calculated using a back titration method. This method integrates interfering element separation, ion exchange purification, back titration, and automated potentiometric detection technologies, and optimizes the electrode system. This method has the advantages of high accuracy, good precision, strong anti-interference ability, and relatively simple and reliable operation, and is suitable for the accurate determination of platinum content in platinum jewelry and platinum alloys of various purities such as Pt900, Pt950, and Pt990.

The invention relates to the technical field of potentiometric titration electrode supports, and discloses a potentiometric titration electrode support and a storage box, the potentiometric titration electrode support comprises a storage box main body, the upper surface of the storage box main body is provided with a sealing cover, and the storage box main body is internally provided with an electrode support main body; a lifting mechanism for conveniently controlling the electrode support main body to ascend and descend is arranged in the storage box main body, a temperature control mechanism for conveniently controlling the temperature and humidity in the storage box main body is arranged at the bottom of the storage box main body, the side cavities are formed in the two sides of the interior of the storage box main body, and the lower fixing plates are fixedly connected to the inner walls of the side cavities. According to the potentiometric titration electrode support and the storage box, a lower fixing plate, an upper fixing plate and a limiting sliding rod are arranged in side cavities formed in the two sides of an inner cavity of a storage box body, and a limiting plate and a lifting plate which are fixedly connected to the two sides of an electrode support body are arranged on the limiting sliding rod, a motor and a lead screw which are installed in the side cavities; therefore, the electrode support body can be controlled to ascend and descend in the storage box body.

The invention relates to the technical field of chemical analysis of oil products, and particularly discloses a method for judging an acid value titration end point of electric oil based on a color titration method. The method comprises the following steps: acquiring time-varying data of a solution color depth value in a titration process in real time by virtue of a spectrum color sensor, fitting a color titration curve by virtue of a high-order polynomial, calculating the curvature of the fitted curve point by point, and taking a curvature peak point which appears for the first time and has a curvature value of 0.2-2 as a titration end point. The method overcomes the defects that a traditional indicator titration method is strong in subjectivity, an automatic potentiometric titration method is easy to pollute an electrode and has no potential jump, and the like, avoids adverse effects of colors of different oil samples on the RGB value of the titration end point when the end point is judged by the color RGB value in an existing color titration method, and is objective and accurate in titration end point judgment, excellent in repeatability and high in accuracy. The method is suitable for measuring the acid value of electric oil. The method is easy and convenient to operate, economical, environmentally friendly, efficient, accurate and high in application and popularization value.

A positive electrode material and a preparation method therefor, and a lithium-ion battery. The positive electrode material has a general chemical formula of LiNiaCobMncMdO2, wherein 0.7<a<0.98, 0<b<0.3, 0<c<0.3, 0<d≤0.01, a+b+c=1, and M is a doping element. An acid-base potentiometric titration test is performed on the positive electrode material by using a potentiometric titrator, with hydrochloric acid having a concentration of 0.02 mol / L as a titration agent, and therefore a curve graph showing the relationship between the differential value dE / dV and the potential E is obtained by means of the differentiation of the potential E with respect to the consumed volume V of the hydrochloric acid. In the curve graph showing the relationship between the differential value dE / dV and the potential E, the positive electrode material has a first characteristic peak when the potential E is within the range of -200 mV to -50 mV, with the peak area of the first characteristic peak being A; the positive electrode material has a second characteristic peak when the potential E is within the range of 120 mV to 250 mV, with the peak area of the second characteristic peak being B; the positive electrode material has at least one characteristic peak when the potential E is within the range of -50 mV to 120 mV, with the sum of the peak areas of the at least one characteristic peak being C; and the residual alkali conversion coefficient of the positive electrode material is ξ, and 0.200≤ξ≤0.350. The positive electrode material is slightly influenced by water vapor, and the content of a residual alkali on the surface of the material is low; therefore, the stability of the surface structure of the positive electrode material can be improved, and side reactions on the surface of the positive electrode material can be effectively reduced, thereby improving the capacity and cycling stability of the positive electrode material.

The invention belongs to the technical field of detection, and particularly relates to an ammonium fluoride detection method and application. The method comprises the following steps: detecting the content of free acid in an ammonium fluoride aqueous solution and / or the content of ammonium fluoride by adopting a potentiometric titration method, recording a potential jump point in the detection process, measuring the consumption of a titration solution, and calculating to obtain the concentration of free acid (hydrofluoric acid) and / or the concentration of ammonium fluoride. The detection method disclosed by the invention overcomes the defects of environmental pollution and influence on body health caused by the fact that formaldehyde needs to be added to promote H < + > release in a traditional acid-base titration method; and meanwhile, the problem of inaccurate detection result of incompletely ionized weak acid and weak base salt by potentiometric titration is solved. According to the technical scheme, detection is accurate and efficient, the obtained concentration content result is more accurate compared with manual titration, and the method is particularly suitable for in-plant and out-plant detection of electronic-grade ammonium fluoride.

The invention discloses a concentration measuring device with automatic weighing and automatic dilution functions, which realizes full-process automation of sample weighing, intelligent dilution and potentiometric titration by virtue of a symmetrical partition design of a left reagent bottle component and a right sample dilution system and in combination with a high-precision mechanical arm, a dynamic dilution compensation algorithm and a micro-upgrading titration cell. A split type magnetic coupling peristaltic pump, a multi-shaft linkage stirring mechanism and an anti-pollution electrode probe are innovatively adopted, and the detection precision (the weighing error is smaller than or equal to 0.1 mg, and the dilution repeatability CV is smaller than 0.5%) and the efficiency (the single sample detection period is smaller than or equal to 5 minutes) are remarkably improved. The device is particularly suitable for high-throughput analysis of trace samples, and meets the strict requirements of the fields of biological medicine, environmental monitoring and the like on automation and pollution prevention.

The invention belongs to the technical field of chemical substance purity determination, relates to phosgene, and discloses a liquid phosgene purity determination method which comprises the following steps: S1, subpackaging phosgene; s2, preparing phosgene absorption liquid; s3, carrying out reaction absorption of phosgene; s4, carrying out titration pretreatment; s5, performing potentiometric titration by using a potentiometric titrator; s6, carrying out blank titration comparison; and S7, determining a calculation formula, and calculating the phosgene purity. According to the method, the phosgene reacts with the sodium hydroxide to generate sodium chloride, sodium carbonate and water, the Cl <-> content in the phosgene-sodium hydroxide absorption liquid is measured by a potentiometric titration method, the purity of the high-purity liquid phosgene is measured by a chemical titration method for the first time, the experiment is convenient, the operation is convenient, and the numerical value is reliable.

According to the analysis method for cooperatively controlling the total iron content in the ferrous oxalate based on the oxidation masking method, the accuracy and repeatability of iron content determination are ensured through multi-step cooperative control, and the analysis method is suitable for industrial quality inspection and scientific research analysis. According to the method, an ammonium persulfate-mixed acid system is adopted, Fe is completely oxidized into Fe under the heating condition, errors caused by incomplete oxidation of Fe are eliminated, a nitrilotriacetic acid masking agent is added, free Fe in a sample is complexed, and hydrolytic precipitation of Fe is prevented. And carrying out potentiometric titration by adopting an EDTA standard solution until a potential jump point appears, so as to eliminate human judgment errors. The method can be applied to the fields of lithium battery positive electrode materials, mineral analysis, environment monitoring and the like, and is particularly suitable for accurate detection of a Fe / Fe coexistence system.

The application relates to the technical field of potential titration prediction and correction, in particular to a potential titration end point prediction and abnormal value correction method based on deep learning, which comprises the following steps: acquiring potential change data in a potential titration process, basic data of a titrant and parameters of a sample to be measured; determining whether it is a suspected abnormal potential according to whether the potential change slope exceeds a preset value and / or whether the potential change violates monotonicity; predicting the abnormal potential type based on the mutation amplitude of the suspected abnormal potential and the preset amplitude comparison; predicting whether it is a weak abnormal potential by whether the local curvature change rate of the weak abnormal potential adjacent potential exceeds a preset value and the time sequence correlation; and determining the correction method according to the comparison result of the abnormal potential duration, the abnormal value deviation degree and the preset value. The application improves the accuracy of the weak abnormal condition judgment of the potential titration technology, and further reduces the error of the analysis result.

This invention provides a method for determining the property parameters of acidic functional group chelating resins based on potentiometric titration, comprising the following steps: preparing a potentiometric titration system including an acidic functional group chelating resin and an acidic titration medium; performing potentiometric titration using a titrant to obtain the electrode potential at titration equilibrium; and obtaining the property parameters of the acidic functional group chelating resin based on the electrode potential. The measurement method of this invention has high accuracy.