14 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 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 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 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 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.

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 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 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.

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.

The invention provides a chloride ion potentiometric titration error prediction method based on a neural network. The method comprises the following specific steps: (1) selecting factors which can influence a test result in a thermal power plant desulfurization wastewater chloride ion determination process as research objects; (2) measuring corresponding actual errors of the desulfurization wastewater sample as basic data; (3) analyzing reliability factors influencing errors of the chloride ion potentiometric titration method; and (4) taking the reliability factor as an input variable, establishing a BP neural network model for prediction, and obtaining a prediction result. According to the method, errors of chloride ion monitoring caused by various influence factors in the desulfurization wastewater monitoring process in practical application can be predicted, and the accuracy of thermal power plant wastewater quality analysis is improved.

The invention provides a method for titration determination of platinum content in platinum jewelry by an automatic potentiometric method, and relates to the technical field of precious metal analysis and detection. The method mainly comprises the following steps: dissolving a platinum jewelry sample with aqua regia, and precipitating and separating precious metal interference elements such as palladium, gold and silver by using a separation reagent. And enabling the platinum to pass through a strongly basic anion exchange resin column, so that the platinum is selectively adsorbed in the form of chloroplatinic acid radical complex anions, and obtaining a purified platinum solution. And calculating the content of platinum by adopting a back titration method. The method integrates interference element separation, ion exchange purification, back titration and automatic potential detection technologies, optimizes an electrode system, has the advantages of high accuracy, good precision, strong anti-interference capability and relatively simple and reliable operation, and is suitable for accurate determination of the platinum content in platinum jewelry and platinum alloy with various purities such as Pt900, Pt950, Pt990 and the like.

The invention discloses a method for determining the content of chloride ions in a power battery electrolyte, and belongs to the technical field of chemical analysis, and the method comprises the following steps: adding a 0.5 moL / L alkali solution into the electrolyte to adjust the pH value to 9-13, heating at 65 DEG C until the solution is not layered, adjusting the pH value to 2-5 by using an acid solution, adding ethanol to obtain a to-be-detected solution, and measuring the content of chloride ions in the to-be-detected solution according to the concentration of chloride ions in the to-be-detected solution; and finally, detecting the to-be-detected liquid by adopting a potentiometric titration method. According to the method, the trace chloride ions in the power battery electrolyte can be detected, the method is high in accuracy and good in repeatability, the result can be rapidly fed back to guide production, and the production requirement is met.

The utility model relates to the field of water quality analyzers, and discloses a water quality analyzer based on potentiometric titration, which comprises a base, the top of the base is fixedly connected with a liquid containing tank, the bottom of the liquid containing tank is communicated with a water outlet pipe, the water outlet pipe penetrates through the base and extends to the bottom of the base, a valve is arranged on the outer wall of the water outlet pipe, and the valve is connected with the liquid containing tank. Two testing electrodes are fixedly embedded in the top of the liquid containing tank, the tops of the two testing electrodes are electrically connected with electric wires, one end of each electric wire is electrically connected with a storage battery, and the bottom of the storage battery is fixedly connected with the top of the base. According to the utility model, the use is simple, the sealing column seals the water inlet hole through the elastic force of the spring, so that the liquid can be directly sealed after being poured so as to prevent air from being in contact with the liquid in the liquid containing tank, the liquid level height in the liquid containing tank can be known by observing the measuring ruler, and the base adopts a small-size design, so that the handle can be directly lifted to drive the whole base to move.