An embodiment provides a method for determining the alkalinity of an aqueous sample using an alkalinity sensor, including: monitoring the pH of an aqueous sample using a pH sensor in a sample cell, the pH sensor including a pH sensor electrode made of boron-doped diamond; generating hydronium ions, using a hydronium generator, in the aqueous sample in the sample cell, the hydronium generator including a hydronium-generating electrode; changing the pH of the aqueous sample by causing the hydronium generator to generate an amount of hydronium ions in the aqueous sample; quantifying and converting a current or charge to the number of hydronium ions produced to an end point of the electrochemical titration, the end point correlating to the alkalinity of a sample; and analyzing the alkalinity of the aqueous sample based on the generated amount of hydronium ions and the resulting change in pH monitored by the pH sensor.

Systems and methods for this disclosure describe systems and methods that are directed to monitoring active clay in water-based drilling fluid may be provided. A method for monitoring active clay concentration while drilling may be provided. The method may include providing a sample of water-based drilling fluid. The method may further include adding methylene blue to the sample in a methylene blue titration. The method may further include performing an impedance measurement on the sample during the methylene blue titration. The method may further include determining an endpoint of the methylene blue titration using a phase angle measurement from the impedance measurement. The method may further include correlating the endpoint to the active clay concentration of the sample. The method may further include determining a treatment for the water-based drilling fluid based on the active clay concentration.

The present invention discloses a spectral-potentiometric-thermometric multi-dimensional titration analysis instrument, which comprises a spectral titration measurement device, a thermometric titration measurement device and a potentiometric titration measurement device which are arranged in parallel, meets the simultaneous measurement requirements of different analysis methods in chemical analysis, improves the measurement precision of different measurement methods, and effectively reduces the workload of separate experiments. The present invention further provides a usage method of the analysis instrument, provides analysis results of different angles and different characterization parameters for the change process of the material structure in the chemical reaction by conducting comparison analysis on data obtained using different measurement techniques, and effectively reduces the workload of titration analysis.

A cell and/or a measuring instrument are arranged for coulometric titration. The cell has first and second electrochemical half-cells, each of which is connected into a regulated circuit and each of which has an associated electrode. The second electrode (3) is immersed in an electrolyte (2) that is solid or solidified and fills a second housing (1). The second housing is closed, with charge and material exchange only possible through a diaphragm (4) that is disposed between the respective electrochemical half-cells. The electrolyte contains a first redox partner that, along with at least one second redox partner, is part of a redox system. The redox partners are selected to substantially suppress gas development inside the cell during operation. The first electrode and the second housing are disposed in a first housing so that at least the diaphragm and the first electrode are in contact with a sample during operation.

The disclosed subject matter relates to techniques for a titration-based analytical method for measuring gold (Au) concentration in Au processing solution. An example method can include an addition of a complexing agent and/or pH adjustment to achieve a sharp inflection point in titration curve.

An embodiment provides a method for determining the alkalinity of an aqueous sample using an alkalinity sensor, including: monitoring the pH of an aqueous sample using a pH sensor in a sample cell, the pH sensor including a pH sensor electrode made of boron-doped diamond; generating hydronium ions, using a hydronium generator, in the aqueous sample in the sample cell, the hydronium generator including a hydronium-generating electrode; changing the pH of the aqueous sample by causing the hydronium generator to generate an amount of hydronium ions in the aqueous sample; quantifying and converting a current or charge to the number of hydronium ions produced to an end point of the electrochemical titration, the end point correlating to the alkalinity of a sample; and analyzing the alkalinity of the aqueous sample based on the generated amount of hydronium ions and the resulting change in pH monitored by the pH sensor.

A method for capturing carbon dioxide includes: spraying an alkaline solution through a first spray structure; temporarily storing a solution, in a first temporary storage structure, and making the solution flow out through the first spray structure; detecting a concentration of hydroxide and/or a concentration of carbonate of the solution, and supplementing one of an alkaline solution and water into the first temporary storage structure according to the concentration of the hydroxide and/or the concentration of the carbonate; and in a case that the concentration of the hydroxide is less than or equal to m and the concentration of the carbonate is n, controlling a first pump body or a third pump body to stop running, so that the solution enters an electrolysis device for an electrolysis. Adopting the present disclosure solves problems in that capture efficiency of carbon dioxide gas and overall energy consumption are relatively difficult to control.

A system and method for determining organic chlorine content in petroleum or petrochemical streams are disclosed. The system comprises an injection module configured to introduce a sample, consisting of a 204 C. cut of washed naphtha or equivalent, into a gas stream; a gas supply unit configured to deliver a gas mixture of approximately 80% oxygen and 20% inert gas selected from argon, helium, or nitrogen, into the injection module; a combustion unit maintained at approximately 800 C. to convert chlorine in the sample to chloride and oxychlorides; a titration cell, comprising: an electrolyte containing 75% acetic acid in water, a silver ion solution to react with chloride ions in the sample, resulting in a measurable electrochemical reaction; and a microcoulometer configured to measure the electric current required to replace consumed silver ions in the titration cell, wherein the measured current is indicative of the organic chlorine content.

A method for determining the content of oxalic acid in dimethyl oxalate, comprising the following steps: determining the content of total acid in a dimethyl oxalate sample; determining the content of nitric acid in the dimethyl oxalate sample; subtracting the content of nitric acid from the content of total acid, and the resulting value is the content of oxalic acid in the dimethyl oxalate sample. The method overcomes the difficulty of measuring two mixed acids separately, avoids the problem of high determination results of oxalic acid caused by the reaction of nitric acid impurities, which are also acidic substances, during titration, and eliminates the interference of nitric acid and solution base.

A residual acid analysis method for an alcohol compound is provided. The residual acid analysis method includes providing an organic solvent and placing the organic solvent into a distillation apparatus to distill the organic solvent and obtain a purified organic solvent from a middle fraction of a distilled liquid distilled from the distillation apparatus; mixing an alkaline inorganic compound and at least a part of the purified organic solvent to form a titration liquid; mixing a diol compound to be measured and at least another part of the purified organic solvent to form a test sample; and using the titration liquid to perform an acid-base titration on the test sample to analyze a residual acid content of the diol compound. An equivalent concentration of the alkaline inorganic compound in the titration liquid is not greater than 0.005 N.