51 results about "Eriochrome Black T" patented technology

The invention relates to a water harness on-line measurement device. A measurement method of the water hardness on-line measurement device based on solution image technology is characterized by adding dropwise EDTA into a quantitative water solution with the pH of 10.0 plus or minus 0.1 by using a constant flow adding pump with chrome black T or acid chrome blue K as indicator, L-cysteine hydrochloride and triethanolaminesolution as screening agent and ethylenediaminetetraacetic disodiumsalt solution as titrant, recording the volume of added EDTA (Ethylene Diamine Tetraacetic Acid) solution by a computer, simultaneously collecting water solution image colors by using a CCD (Charged Coupled Device) image sensor, displaying image color RGB (Red, Green and Blue)-titrating solution volume real-time curve on a computer screen, and calculating the water hardness according to the titrating solution volume corresponding to the inflection point of the RGB-titrating solution volume curve, wherein the detection precision is improved by adopting a color constancy algorithm based on a neutral network to reduce the interference of factors such as a light source, sensor noise and the like. The invention have the choices of high hardness and low hardness on-line measurement, is simple and convenient in operation, and can be used in the industries of electric power, petroleum, chemical industry, metallurgy and the like.

The invention discloses a charged TiO2/polyelectrolyte composite nanofiltration membrane as well as a preparation method and an application thereof, and belongs to the technical field of membrane separation. The preparation method comprises the following steps: firstly, the surface of a base membrane is charged, so that the base membrane and polyelectrolytes can conveniently generate an electrostatic effect; secondly, the composite nanofiltration membrane is prepared with a method for alternatively depositing anionic and cationic polyelectrolytes and performing electrostatic layer-by-layer self-assembly. Inorganic nanoparticles adopted in the preparation method are modified negatively charged/positively charged TiO2 nanoparticles; as TiO2 has the advantages of good photocatalytic performance, good hydrophilicity and the like, TiO2 is combined with layer-by-layer self-assembly to prepare the TiO2/polyelectrolyte composite nanofiltration membrane; the preparation method is simple and convenient to operate and is an environment-friendly preparation method; moreover, the prepared TiO2-containing composite nanofiltration membrane has very good hydrophilicity and charge performance, has good pollution resistance, is uniform in structure and can be used for removing divalent metal ions such as Ni<2+> and the like in wastewater as well as dye molecules such as dimethylphenol orange, eriochrome black T and the like at the same time, thereby having a good application effect.

The invention belongs to the technical field of water treatment in water pollution prevention and control, and relates to the treatment of dye wastewater, in particular to a method for treating dye wastewater by utilizing modified straws. The method comprises the following steps of performing straw modification by virtue of a two-step method, namely pre-treating rice straws by virtue of sodium hydroxide, and performing modification reaction on the pre-treated rice straws and tetradecyl trimethyl ammonium chloride; removing orange yellow II, methylene blue and eriochrome black T dyes from a water body to finally realize the treatment of the dye wastewater by virtue of the modified straws. The modified rice straws and tetradecyl trimethyl ammonium chloride are subjected to mixed reaction according to a mass ratio of 1:1 to 1:1.5; the content of sodium hydroxide is 10 to 30 mass percent. According to the technical scheme, the good coagulation effects, high decolorization capability and convenience in use are achieved, and the cost is lowered; agricultural straws can be recycled, and meanwhile, the dye wastewater can be decolored.

The invention discloses a method for continuously determining the content of calcium oxide and magnesium oxide in bentonite. According to the method, a bentonite sample is added to a polytetrafluoroethylene plastic beaker, another beaker is not filled with the bentonite sample and serves as a blank control, then hydrochloric acid and nitric acid-hydrofluoric acid are added for dissolution respectively, perchloric acid is added for smoking, then hydrochloric acid is added to heat and dissolve salt, test solutions are transferred to large volumetric flasks respectively and diluted to a constant-volume scale, each solution is split into two parts of solutions with equal quantities; triethanolamine, water and hydroxylamine hydrochloride are added sequentially to one of the sample and the blank control, a potassium hydroxide solution and an appropriate amount of calcein are added, an EDTA (ethylene diamine tetraacetic acid) standard solution is adopted for titration until fluorescent green disappearance, the volume is recorded, and the content of calcium oxide is calculated; triethanolamine, water and hydroxylamine hydrochloride are added sequentially to the other one of the sample and the blank control, an ammonia-ammonium chloride buffer solution and an appropriate amount of eriochrome black T indicator are added, the EDTA standard solution is adopted for titration until purple red turns into blue, the volume is recorded, and the content of magnesium oxide is calculated.

The invention discloses a method for measuring the metallic magnesium content of a briquette nodulizing agent by using complexometry. The method comprises the steps of dissolving metallic magnesium in a test sample in dilute acetic acid, removing other Insoluble matters through filtering and washing, and fixing the volume of the filtrate in a volumetric flask; and weighing a certain volume of filtrate, regulating the pH value to 6-7 with ammonia water, separating interference elements with a copper reagent, complexing calcium with EGTA (ethylene glycol tetraacetic acid) when the pH is 10, and performing complexometry on magnesium by using EDTA (ethylene diamine tetraacetic acid), wherein eriochrome black T is an indicator. The method can detect that the metallic magnesium content in a briquette nodulizing agent sample is 5-15%, which nearly covers the metallic magnesium distribution gradients of all nodulizing agents in the production process, and can be applied to quantitative detection of the metallic magnesium in the laboratory briquette nodulizing agent for a long term. The method has the advantages of simplicity, fastness, high accuracy and precision and the like.

The present invention discloses a method for determination of magnesium content in aluminum alloy, including: dissolving an aluminum alloy sample, using one or more compounds selected from the group consisting of mercapto-containing compound, acetone cyanohydrin, β-aminoethyl mercaptan, triethanolamine, tetraethylenepentamine, ethylene diamine and oxydol as masking agent, using eriochrome black T or methyl thymol blue as indicator, and using EDTA or CDTA to titrate the sample.

The invention discloses a method for measuring the magnesium and zinc content in alloy at the same time. The method comprises the steps that A, acid is used for dissolving the alloy to obtain a first solution; B, the first solution is prepared into a magnesium and zinc ion water solution; C, the magnesium and zinc ion water solution is taken to serve as a titration sample, an NH4Cl-NH3.H2O buffering solution and an eriochrome black T indicator are sequentially added into the titration sample, the pH of the titration sample is kept to be 9-11, and the titration sample is shaken up uniformly to obtain a titration solution; D, an EDTA-2Na water solution is adopted for titraging the titration solution, titraging is stopped until the titration solution is turned into azure from wine red, and the volume use amount of the EDTA-2Na water solution is recorded; E, the mass percent of magnesium and zinc in the alloy is calculated. The method is fast and simple, and the measuring time is short.

The invention discloses a method for measuring the calcium oxide and magnesium oxide content of a tundish covering agent. The method has the advantages of being higher in speed, accuracy and efficiency. The method comprises the following steps: dissolving a test sample with hydrochloric acid and hydrofluoric acid, adding nitric acid, adding perchloric acid for smoking, adding hydrochloric acid after cooling, and performing heating to dissolve salts; adjusting the pH value to 7 with ammonia water, heating the test solution till the test solution boils, taking down and slightly cooling the test solution, filtering the test solution in a volumetric flask, washing precipitates for 7 to 8 times with a hot ammonium chloride solution, diluting the solution to a scale for volume fixation after cooling, equally dividing the solution into two parts for putting into two beakers; for one of the two breakers, adding small amounts of triethanolamine, water and hydroxylammonium chloride, adding a potassium hydroxide solution to adjust the pH value to 12, adding a proper amount of calcein, and performing titration with an EDTA standard solution until fluorescence green disappears to obtain the amount of calcium; for the other one of the two breakers, adding small amounts of triethanolamine, water and hydroxylammonium chloride, adding an ammonia-ammonium chloride buffer solution to adjust the pH value to 10, taking eriochrome black T as an indicator, and performing titration with the EDTA standard solution until the solution is pure blue to obtain the total amount of calcium and magnesium.

The invention discloses a method for measuring the content of calcium oxide and magnesium oxide in refined slag and aims to provide a method which can be used for measuring the content of calcium oxide and magnesium oxide in the refined slag quickly, accurately and efficiently. A sample is dissolved with hydrochloric acid and nitric acid-hydrofluoric acid, perchloric acid is added, the mixture smokes and is taken off and cooled, hydrochloric acid is added along the wall of a beaker carefully, and salt is heated and dissolved; a solution is transferred to a large volumetric flask with secondary water, diluted until the solution reaches a predetermined scale and shaken uniformly, and two parts of the solution are taken out and put into two small beakers; triethanolamine, water and a little hydroxylammonium chloride are added to one part of the solution, a potassium hydroxide solution is added until the pH value of the mixture is 12, a proper amount of calcein is added, an EDTA (ethylene diamine tetraacetic acid) standard solution is dropwise added until fluorescent green disappears, and accordingly, the content of calcium is obtained; triethanolamine, water and hydroxylamine hydrochloride are added, an ammonium-ammonium chloride solution is added until the pH value of the mixture is 10, eriochrome black T is taken as an indicator, an EDTA standard solution is dropwise added until the mixture is in pure blue, and the content of calcium and the content of magnesium can be obtained.

This invention provides a hardness measurement reagent for measuring the hardness of water, the reagent being capable of causing the test water to change color sesitively at the vicinity of a controlled hardness. The reagent of this invention contains a coloring material selected from an Eriochrome black T (EBT) or a Calmagite, triethanolamine, glycol compound, and an alkali metal salt of a chelate agent.

To provide a hardness measurement reagent unaffected by an M alkalinity in hardness measurement. A hardness measurement reagent as a one-solution type reagent includes a dye chosen from Eriochrome Black T (EBT) and Calmagite, triethanolamine, a glycol compound, and a pH buffer, in which the pH buffer includes a combination of amines selected from primary amines and secondary amines and a salt of a weak base.

The invention discloses a measuring method for the content of calcium oxide and magnesium oxide in open-hearth furnace slag, converter slag and electric furnace slag. The measuring method has the advantages of being rapider, more accurate and more efficient. A sample is dissolved with hydrochloric acid, nitric acid-hydrofluoric acid, perchloric acid is added for smoking, and after taking down and cooling, hydrochloric acid is added to heat and dissolve salt; the pH value of the test solution is adjusted to be 7 with ammonium hydroxide, the test solution is heated to be boiled, taken down, slightly cooled and filtered in a volumetric flask, sediment is washed 7-8 times with a hot ammonium chloride solution, after being cooled, the solution is diluted to scales for volume setting, two parts of equal solutions are taken respectively and put in two flasks, triethanolamine, water and a small amount of hydroxylamine hydrochloride are added to one part, the pH value is adjusted to be 12 after a potassium hydroxide solution is added, a proper amount of calcein is added, and titration is conducted with an EDTA standard solution till an end point that fluorescent green disappears and the amount of calcium is obtained; triethanolamine, water and a small amount of hydroxylamine hydrochloride are added to the other part, the pH value is adjusted to be 10 after an ammonia-ammonium chloride buffer solution is added, eriochrome black T serves as an indicator, and titration is conducted with the EDTA standard solution till an end point of pure blue and the resultant amount of calcium and magnesium is obtained.

The invention discloses a method for analyzing cadmium chloride in an acid cyanide-free cadmium plating solution. The method includes the steps that a coordination agent in the acid cyanide-free cadmium plating solution is oxidized with ammonium persulfate under the strong acid condition so that cadmium ions can be released from coordination ions; iron ions are masked with ascorbic acid and aluminum ions are masked with triethanolamine under the condition that pH ranges from 9.5 to 10, an excess EDTA standard solution is added to coordinate with cadmium ions, eriochrome black T serves as an indicator, EDTA is subjected to back titration with a zinc sulfate standard solution, and the mass concentration of cadmium chloride in the plating solution is calculated with a minusing method. According to the method, in the testing process, sulfuric acid is added into the tested solution to make the tested solution have strong acidity, and then the coordination agent is completely oxidized with ammonium persulfate under the heating condition, so that interference of the coordination agent with cadmium chloride determination is eliminated. The method is accurate in determination result and superior to an existing method.

The invention provides a method for testing constant cadmium and zinc in cadmium zinc telluride crystal. The method provided by the invention comprises the following steps: taking a solution obtained by dissolving a proper amount of a sample solution of the cadmium zinc telluride crystal to be tested or a proper amount of a solid sample of the cadmium zinc telluride crystal to be tested, adjusting pH value of the solution to neutral by adding ammoniacal liquor (1+1) to and adjusting pH value of the solution to 10 by adding a proper amount of an ammonia-ammonium chloride buffer solution and remaining stable; adding a proper amount of a surfactant into the solution, adding a proper amount of an eriochrome black T indicator, and carrying out complexometric titration by the use of a complexing agent EDTA to turn the solution from purple to pure blue so as to obtain total amount nCd+Zn of cadmium and zinc, wherein molar concentration of the complexing agent EDTA is C1 and the use amount is V1; adding a proper amount of DDTC sodium salt to fully dissolve, selectively precipitate cadmium by DDTC sodium salt and releasing the same amount of EDTA, carrying out titration on EDTA by the use of a magnesium nitrate solution until the solution turns light red so as to obtain cadmium with the amount of nCd and mass of mCd, wherein molar concentration of the magnesium nitrate solution is C2 and use amount is V2; and obtaining zinc with amount of nZn and mass of mZn according to a difference method.

An indicator capable of rapidly determining hot water boiler feedwater hardness is characterized by being prepared by the following components in parts by weight: 50-55 parts of sodium chloride, 15-20 parts of sodium carbonate, 25-30 parts of sodium bicarbonate, 1.6-2.0 parts of disodium ethylene diaminetetraacetate and 0.18-0.20 part of eriochrome black T. The components of the indicator do not contain crystal water, therefore the indicator is stable in property and not prone to deliquescence and overcomes the defect that the disodium hydrogen phosphate and sodium dihydrogen phosphate contain lots of crystal water, thus being prone to deliquescence. The invention adopts the eriochrome black T as the color indicator, thus overcoming the defect that the color indicator is unstable when the ratios of acid chrome blue K and naphthol green B misfits each other when the KB indicator is adopted. The indicator is simple in production process, low in raw material cost and rapid and convenient in detection.

The invention discloses a method for continuous determination of the content of Ca, Mg and Ba in Si-Ca-Ba-Mg alloy. The method includes the steps that a Si-Ca-Ba-Mg alloy sample is added into one beaker, no sample is added in the other breaker which serves as blank control, nitric acid-hydrofluoric acid mixed solutions are added respectively for dissolving the sample, and sulfuric acid is added till smoking happens; afterwards, hydrochloric acid is added for dissolving slats, water and hydroxylamine hydrochloride are added and heated to be boiled till the solutions are changed to be colorless from being yellow, the solutions are filtered into a large volumetric flask, sediments are washed by dilute sulphuric acid and water, and the sediments together with filter paper are placed into a porcelain crucible; ashing, firing and weighing are carried out, and accordingly the content of the Ba is obtained; two groups of quantitative solutions are selected to be put in beakers from the constant volume solution and the blank solution, one group is sequentially added with triethanolamine, water, hydroxylamine hydrochloride and a potassium hydroxide solution, several drips of magnesium sulfate are added, a proper quantity of calcein indicator is added, and EDTA is used for titration till fluorescent green disappears, and accordingly the content of the Ca is obtained; the other group is sequentially added with triethanolamine, water, hydroxylamine hydrochloride and an ammonia-ammonium chloride buffered solution, an eriochrome black T indicator is added, EDTA is used for titration till fuchsia is turned into blue, and accordingly the content of the Mg is obtained.

The invention relates to a method for preparing low-zinc low-iron clear rongalite, which comprises the steps that: rongalite solution is used as a raw material and quinoline organic precipitator is used for precipitating zinc and ferrous ions in the solution before concentration; then, sampling and filtering are carried out, ammonia-ammonium chloride with the pH of 10 is used for buffering the solution with Eriochrome black T as a visualization reagent, and the content of the residual zinc ions in filtrate is measured by colorimetry; after the measured value meets the control requirement of 1 to 3mg/L, stirring is stopped, after precipitation and aging are carried out for 2 to 3 hours, precipitates are filtered away and then the filtrate is colorless and transparent; then, cooling for crystallization, crushing and packaging are carried out for obtaining the products of the clear rongalite with zinc and ferrous contents lower than 10PPm after the filtrate is concentrated to the content of over 98 percent at a vacuum level ranging from minus 0.085 to minus 0.095mPa and temperature lower than 75 DEG C. The invention has the advantages that the products prepared by the method have good stability and zinc and ferrous contents of lower than 10PPm, thus meeting special requirements on rongalite products by industries such as medicine and rubber, etc.

The invention discloses a copper reagent separation-EDTA titration method for measuring magnesium content of aluminum alloy. The copper reagent separation-EDTA titration method comprises the following steps: weighing 0.5000+/-0.0100 g of an aluminum alloy sample into a beaker, adding 1-2 g of sodium hydroxide and 5-10 mL of water, heating for dissolving after violent reaction, and filtering after cooling; eluting the precipitate into the beaker by using 10-20 mL of hot hydrochloric acid (1+1) and 15-20 mL of hydrogen peroxide, heating till a boiling state to completely remove the hydrogen peroxide, regulating pH to 2-6, transferring to a volumetric flask, adding a copper reagent solution till the final concentration of a copper reagent in the volumetric flask is 0.25-0.75 g/ L, filtering, taking 25.00 ml of a filtrate, adding 60-70 ml of boiling water, 8-10 mL of a buffer solution with the pH of 10 and an eriochrome black T indicator, titrating by using 0.01 mol/L of an EDTA standard solution till a blue color, and recording the using amount of the EDTA standard solution.

The invention discloses a preparation method for eriochrome black T test paper for urinary calcium ions. The preparation method is characterized in that the eriochrome black T test paper for urinary calcium ions is made of filter paper impregnated with eriochrome black T, triethanolamine, ammonia water, ammonium chloride, sodium dodecyl sulfate, Mg-EDTA and polyvinyl alcohol, one square centimeter of filter paper contains 0.6-2.5 mg of eriochrome black T, 0.2-1.5 mg of triethanolamine, 0.6-3.0 mg of ammonia water, 0.05-1.0 mg of ammonium chloride, 0.1-2.0 mg of Mg-EDTA and 0.5-2.0 mg of polyvinyl alcohol, and quantitative filter paper can be used as the filter paper. The eriochrome black T test paper for urinary calcium ions is convenient to carry, easy and fast to operate, visual in detection, good in selectivity, and high in accuracy and sensitivity during detection. Conditions required in the preparing process of the test paper for urinary calcium ions are easy to control, energy consumption is low, and operation is easy.

The invention provides a detection reagent for heavy metals in water and a detection method of the detection reagent. The detection reagent comprises components in parts by weight as follows: 10-15 parts of ethylenediamine tetraacetic acid disodium salt, 5-10 parts of an ammonia solution, 3-5 parts of ammonium citrate, 3-5 parts of sodium erythorbate, 1-3 parts of dimethylglyoxime, 1-3 parts of Eriochrome black T, 1-5 parts of a surfactant, 5-10 parts of n-butyl alcohol, 10-15 parts of ethanol and 40-60 parts of water. The detection method comprises steps as follows: taking two detection reagents with same volumes, adding a to-be-detected aqueous solution to the first detection reagent to form a first mixed solution; adding deionized water with the volume equal to that of the to-be-detected aqueous solution to the second detection reagent to form a second mixed solution; observing color changes of the first mixed solution with the second mixed solution taken as a reference. The detection reagent for the heavy metals in the water is more sensitive in reaction and has the higher detection efficiency.

The invention discloses a hardness indicating agent for detecting whether the value of hardness ions is greater than a management reference value during circulating water treatment, and a preparation method of the hardness indicating agent, and relates to circulating water treatment. The hardness indicating agent for the circulating water comprises the components in percentage by weight: 3.7-7.5 percent of EDTA, 0.45-0.48 percent of borax, 0.02-0.04 percent of a pH conditioning agent, 0.05-0.2 percent of eriochrome black T, 10-20 percent of triethanolamine, and the balance being water. The preparation method comprises the steps of adding water, the pH conditioning agent, EDTA, borax, eriochrome black T and triethanolamine into a container according to the ratio, and stirring for 10-15 minutes at room temperature to obtain a product.

The invention discloses a method for determining biomass aiming at a micro-porous plate fermentation technology. The method comprises the following steps: cleaning a fermentation liquor precipitate subjected to pore plate culture with normal saline for three times, determining magnesium ions inside thallus based on a microplate reader by virtue of an Eriochrome black T dual-wavelength developing method (Delta A=A560-A680), and reflecting the thallus biomass by using the content of the magnesium ions. According to the method disclosed by the invention, the defect that the biomass of the fermentation liquor is difficultly represented by a dry weight weighing method in the micro-porous plate fermentation process is overcome, and based on elimination of a plurality of interference factors, thedetermined value obtained by the method is close to an actual value, and the method has excellent determination result correlation to other biomass determining methods (such as a glucosamine method)and accords with the growth tendency of bacterial amount in a plate culture count method. In a word, the biomass determining method disclosed by the invention is convenient to operate, rapid and accurate, capable of accurately reflecting the bacterial amount variation tendency in the fermentation process, noncorrosive in reagent and small in dose, and has excellent application value.

The invention discloses a method for detecting barium and zinc in a zinc-barium liquid compound stabilizer. The method comprises the following steps: (1) dissolving a zinc-barium liquid compound stabilizer sample by using 120# solvent gasoline, wherein the ratio of the sample quality to the solvent gasoline volume is 1:(10-15) (g/ml); adding absolute ethyl alcohol to metered volume, wherein the metered volume is V, and shaking to be even; (2) transferring two parts of solutions with the same volume prepared in the step (1), adding ammonium fluoride and water to one part of solution to dissolve ammonium fluoride, and then adding an ammonia-ammonium chloride buffer solution of which the pH is 10; adding a plurality of drops of eriochrome black T indicators, carrying out titration by using an ethylene diamine tetraacetic acid (EDTA) standard titration solution until the titration end point of which the solution becomes pure blue; recording the volume V1 of consumed EDTA standard titration solution, calculating the content of zinc in the sample; not adding ammonium fluoride to the other part of solution, and carrying out the same treatment processes; recording the volume V2 of the consumed EDTA standard titration solution, and calculating according to the formula 2, so as to obtain the content of barium in the sample. The method is simple in apparatus, and accurate and reliable in result, and the content of zinc and barium can be respectively determined.

The invention discloses a breeding water body total hardness detection kit, which contains a total hardness test reagent I, a total hardness test reagent II, two bottles of total hardness test reagentIII and a colorimetric bottle, wherein the test reagents I, II and III comprise disodium ethylenediaminetetraacetate, eriochrome black T, ammonium chloride, ammonia water, a synergist, a masking agent, absolute ethanol and distilled water. According to the present invention, the kit has advantages of rapidness, sensitivity, convenient use, obvious reaction, stable quality and the like, can overcome the problems of reagent deterioration, reagent color changing and the like of the common kit during the detection due to the complex operation steps or the long placing time, further has advantagesof simple and efficient operation steps, significant color change reaction and no requirement of the additional equipment, and is suitable for the on-site rapid detection of a variety of water qualities.