Showing papers on "Sodium chlorate published in 2020"

Improved chlorate production with platinum nanoparticles deposited on fluorinated activated carbon cloth electrodes

Abstract: Sodium chlorate is one of the main oxidizing agents used in the wood industry due to their capability of use as an elemental chlorine-free (CEF) bleaching. A simple way to produce chlorates is by the electrolysis of an aqueous sodium chloride (NaCl) solution. In the present study activated carbon cloth electrodes (ACC) modified with fluorine and platinum nanoparticles (Pt–F/ACC and Pt/ACC) were used as one of the electrodes. Electrofluorination was used for fluorination of the anodes and polyol method was used for the synthesis of platinum nanoparticles. Chlorate production using a typical solution of 100 ​g/l of sodium chloride (NaCl) and 2 ​g/l sodium chromate (Na2Cr2O7) and an applied current of 0.540 ​A was studied. Prior to the electrolysis assays, the microstructural properties of the electrodes were characterized by scanning electron microscopy and surface modifications and bonding using infra-red (FTIR) spectroscopy. Electrochemical properties were determined using cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. Interaction between fluorine (F) and platinum (Pt) on the electrode leads to an improvement of the electrocatalytic properties for chlorine evolution as observed from the increase in the current efficiency from 37.5% at 78.5% after 150 ​min of continuous electrolysis using Pt–F/ACC anodes. The results suggest that modified activated carbon material is an attractive and economical alternative as electrodes for chlorate production.

Comparison of the Effect of NaClO 3 and H 2 O 2 on the Molybdenum Leaching from Molybdenite Concentrate

Abstract: In the present study, the leaching of molybdenum from molybdenite concentration in the hydrochloric acid medium was investigated and the comparison was made between the effect of the sodium chlorate and hydrogen peroxide as oxidizing agents on the Mo-dissolution rate. Also, the effect of adiabatic temperature was studied on the Mo-dissolution rate. The leaching parameters were studied, and the optimum conditions were determined as temperature 80 °C, time 4 h, L/S ratio 1:20, 20% of HCl concentration, and 500 rpm as agitation. The results showed that sodium chlorate had a better impression than hydrogen peroxide, almost twice higher than it. Undermentioned optimum conditions, 89.3% of Mo-dissolution rate was achieved.

Effect of metals and Co3O4 on the thermal decomposition reaction of sodium chlorate in an area of refuge

Abstract: Sodium chlorate (NaClO3) is suitable for use in an area of refuge as the backup chemical oxygen source. To explore the catalytic mechanism of metals and Co3O4 on NaClO3, the addition amount was studied. In this research, 18 samples were prepared by adding different concentrations of Fe, Mg, and Mn (2%, 4%, 6%, and 8%) with Co3O4 (2%, 3%, 4%, 5%, and 6%), and some thermogravimetric experiments were conducted. The results show that the initial decomposition temperature of NaClO3 is reduced from 522 to 255–270 °C by Co3O4. There are two stages in the decomposition process of NaClO3 under the catalytic effect of Co3O4. The catalytic effect of 5% Co3O4 on NaClO3 decomposition is the greatest among the tested amounts. In addition, the proportion of metals has little effect on the initial decomposition temperature of NaClO3 when 5% Co3O4 is added, but NaClO3 has better oxygen performance when the mass fraction of metals is 4–8%. The highly active Mg destabilizes the decomposition of NaClO3, and Mn is more suitable than Mg/Fe for addition into NaClO3. The above conclusions help improve the oxygen supply application of NaClO3 in an area of refuge.

Stable composite chlorine dioxide solid lozenge and preparation method thereof

Abstract: The invention discloses a stable composite chlorine dioxide solid lozenge and a preparation method thereof. The composition is prepared from the following components in parts by weight: 6-7 parts of sodium chlorate, 9-10 parts of sodium chlorite, 30-31 parts of sodium dichloroisocyanurate, 32-33 parts of sodium hydrogen sulfate, 3-4 parts of sodium sulfate, 2-3 parts of boric acid, 15-16 parts ofsodium chloride, 2-3 parts of sodium carboxymethyl cellulose, 6-31 parts of an oxidizing agent, 34-36 parts of inorganic acid, 18-20 parts of a diluent and 2-3 parts of an adhesive. The invention relates to the technical field of chlorine dioxide solid agents, and particularly provides the stable composite chlorine dioxide solid lozenge which is portable to use, small in size, high in reaction speed, convenient to store, transport and use, free of operations such as preparation and metering of a user and environment-friendly in residue after use, and a preparation method of the stable composite chlorine dioxide solid lozenge.

Selective oxidation chlorine dioxide oxide sustained-release tablet special for culture pond

Abstract: The invention discloses a selective oxidation chlorine dioxide sustained-release tablet special for a culture pond. The selective oxidation chlorine dioxide sustained-release tablet comprises sodium chlorate, baking soda, solid silicic acid, calcined gypsum powder, water, a solid antioxidant and algae dry powder. The preparation method comprises the following steps: stirring algae dry powder, calcined gypsum powder and water in a food-grade stirrer, respectively adding sodium chlorate, baking soda and solid silicic acid, continuing performing stirring, completely adding the obtained mixture ina food-grade crusher for crushing, filtering out impurities by using a screen, adding the crushed powder into a pressing mold according to the weight of the tablets, and carrying out compression molding pressing to obtain cylindrical or spherical tablets. The invention provides a selective oxidation chlorine dioxide sustained-release tablet special for a culture pond. The composition does not contain chlorine dioxide in the storage process, the shelf life and potential safety hazard defects of the composition are avoided, chlorine dioxide gas is obtained through reaction after the compositionis soaked in water, and bacteria, algae, viruses, microorganisms and an oxidation humic layer are killed.

Method for preparing high-purity chlorine dioxide using combination of methyl alcohol and hydrogen peroxide as reducing agent

Abstract: Provided is a method for preparing high-purity chlorine dioxide using a combination of methyl alcohol and hydrogen peroxide as a reducing agent. The method comprises: injecting concentrated sulfuric acid and sodium chlorate solution into a generator to form a reaction mother solution, making the reaction mother solution maintain an acidity of 5.8-6.2N, a sodium chlorate content of 234-266 g/L and a temperature of 69-73℃; then adding a reducing agent from the combination of methyl alcohol and hydrogen peroxide for reaction to generate chlorine dioxide gas and by-product neutral mirabilite; and cooling the chlorine dioxide gas generated by reaction and then absorbing same with chilled water of 4-10℃ to obtain a chlorine dioxide aqueous solution, and at the same time, filtering, washing and recycling the by-product neutral mirabilite. Compared with only using methyl alcohol as a reducing agent, the method can reduce the chlorine gas content in chlorine dioxide by 60-70%, and can reduce the sulfuric acid consumption by 14-20%; besides, the generated by-product is neutral mirabilite, needing no neutralization treatment for acidic mirabilite.

Method for preparing high-purity chlorine dioxide by using methanol and hydrogen peroxide as reducing agent

Abstract: The invention discloses a method for preparing high-purity chlorine dioxide by using methanol and hydrogen peroxide as reducing agent. The method comprises: concentrated sulfuric acid and sodium chlorate solution are injected into the generator to form the reaction mother liquid. The reaction mother liquid shall be maintained a certain acidity, temperature and sodium chlorate content, and then it is reacted with the reducing agent (methanol and hydrogen peroxide) to produce chlorine dioxide gas and by-product sodium sulfate. The chlorine dioxide gas is cooled and absorbed by low temperature chilled water to obtain an aqueous solution of chlorine dioxide, and by-products are recycled. The chlorine dioxide solution produced by the aforementioned method has a 60-70% reduction in the Cl2 content and 14-20% reduction in sulfuric acid consumption than that of the chlorine dioxide produced by using a single methanol reducing agent, and the by-product produced is sodium sulfate, not sodium hydrogen sulfate, so neutralization reaction treatment is not required.

Chlorine dioxide generating device and application

Abstract: The invention discloses a chlorine dioxide generating device and application. The chlorine dioxide generating device comprises a container in any shape; a partition plate is arranged in the containerand divides the container into two ionization chambers; an electrode is arranged in each ionization chamber, and the electrode is an aluminum-graphene electrode or a graphene-graphene electrode; the two ionization chambers are filled with a sodium chloride aqueous solution, a sodium chlorite aqueous solution, a sodium hypochlorite aqueous solution or a sodium chlorate aqueous solution; the electrodes in the two ionization chambers are connected with a positive electrode and a negative electrode of a direct-current power supply respectively. The chlorine dioxide generating device is simple andeasy to manufacture, and devices in any shape can be manufactured to meet the requirements of different crowds; chlorine dioxide high-purity gas has efficient sterilization and removal effects on allindoor peculiar smells and bacteria, and air can be effectively purified; the chlorine dioxide generating device can also be applied to treatment of boiler combustion waste gas, atmospheric pollutantssuch as sulfur dioxide, nitric oxide and nitrogen dioxide generated by a coal-fired boiler can be removed, the sulfide removal rate is 99%, and the nitride removal rate is 90% or above.

Preparation method of ruthenium hexammine trichloride

Abstract: The invention discloses a preparation method of ruthenium hexammine trichloride The method specifically comprises the following steps: adding a certain amount of chlororuthenium acid salt solid intoa mixed solution of ammonia water and ammonium chloride, heating for boiling, slowly adding hydrazine hydrochloride or hydrazine hydrate into the boiling solution until the solution becomes yellow, continuously boiling for a period of time to obtain a yellow transparent solution, and adding stoichiometric sodium chlorate, potassium chlorate, sodium hypochlorite or potassium hypochlorite into the solution, boiling to react for a certain time, filtering to obtain a precipitate, washing the obtained precipitate twice by using a mixed solution of 20% ammonium chloride and ammonia water in a ratioof 1:1, washing twice by using acetone, and drying to obtain faint yellow ruthenium hexammine trichloride crystals

Organic stable chlorine dioxide disinfectant and preparation method thereof

Abstract: The invention relates to an organic stable chlorine dioxide disinfectant, which is prepared from the following raw materials in parts by weight: 50 to 100 parts of desalted water, 0.1 to 0.2 part of sodium chlorate and/or sodium chlorite, 0.08 to 0.16 part of an activating agent, 1.5 to 3.0 parts of an organic complexing agent and 0.001 to 0.002 part of an inorganic complexing agent. The chlorinedioxide disinfectant has the beneficial effects that a method is provided for application of the chlorine dioxide disinfectant, on-site preparation is not needed, the disinfectant can be sterilized and disinfected under the neutral condition, and certain stable performance is achieved. The organic complexing agent contained in the organic stable chlorine dioxide disinfectant disclosed by the invention is an organic compound with power supply capability; the organic complexing agent can be chelated with chlorine dioxide electron-deficient molecules, that is, the organic compound with the powersupply capability is chelated with chlorine dioxide, a chelation ring contains a plurality of atoms and is very stable, and the relatively stable structure forms a buffer system in a weak acid environment, continuously and slowly releases chlorine dioxide and plays oxidation, disinfection and killing roles.

Preparation method of 6-chloro-2,4-dinitroaniline

Abstract: The invention discloses a preparation method of 6-chloro-2, 4-dinitroaniline. The preparation method comprises the following steps: a, dispersing 2,4-dinitroaniline in hydrochloric acid and a catalyst, and carrying out pulping, wherein the mass fraction of the hydrochloric acid is 1-6 wt%; b, introducing chlorine gas into a pulping material obtained in the step a and carrying out a chlorination reaction; c, adding a sodium chlorate solution into a reaction solution obtained in the step b, and continuing the chlorination reaction, wherein the mass fraction of the sodium chlorate solution is 20%-40%; d, filtering a reaction liquid obtained in the step c, washing a filter cake by a washing device until the pH value of the filter cake is 6.0-7.0, returning mother liquor to the step a to be circularly and indiscriminately used as hydrochloric acid and the catalyst, and discharging the mother liquor into a wastewater treatment system until the concentration of sodium chloride in the mother liquor is saturated; and e, putting the filter cake obtained in the step d into an air flow drying machine for drying to obtain the 2,4-dinitro-6-chloroaniline. The method has the advantages of small overall water consumption and good cleaning effect.

Sodium hypochlorite disinfectant for drinking water and preparation method thereof

Abstract: The invention belongs to the field of disinfectants, in particular relates to a sodium hypochlorite disinfectant for drinking water and a preparation method thereof The sodium hypochlorite disinfectant comprises main materials and auxiliary materials, wherein the main materials comprise water, a sodium hydroxide solution and liquid chlorine; wherein the auxiliary materials comprise chlorine, a sodium carbonate solution and a calcium hydroxide solution, and the main materials and the auxiliary materials comprise the following components in parts by mass: 80-120 parts of the water, 6-10 parts of the sodium hydroxide solution, 2-4 parts of the liquid chlorine, 1-3 parts of the chlorine, 2-5 parts of the sodium carbonate solution and 3-6 parts of the calcium hydroxide solution The liquid chlorine and the chlorine are added for preparation; by slowly adding the liquid chlorine and the chlorine under a low-temperature condition, sodium chlorate can be obtained, the quality of the sodium chlorate is guaranteed, the condition that sodium hypochlorite is possibly decomposed is avoided at a low temperature, the reaction can be accelerated under the condition that the air pressure in a sealed tank is low, meanwhile, stirring and mixing are conducted uninterruptedly, and the maximum sodium hypochlorite can be obtained

System and Method for removing Nitrogen oxides and Sulfur dioxide in flue gas using gaseous chlorine dioxide

Abstract: The present invention relates to a system and method for removing nitrogen oxide (NOx) and sulfur dioxide (SO_2) in exhaust gas using gaseous chlorine dioxide. In detail, according to the system and method of the present invention, gaseous chlorine dioxide generated by using inexpensive sodium chlorate (NaClO_3) as a starting material is supplied into a reaction duct filled with adsorbent and stays between the surface of the adsorbent and pores, so that nitrogen oxide and sulfur dioxide in the exhaust gas are subject to a gas-gas oxidation reaction for a sufficient time. Therefore, it is possible to effectively remove the nitrogen oxide and sulfur dioxide.

High-stability chlorine-containing disinfectant formula and preparation method thereof

Abstract: The invention belongs to the technical field of disinfectant formulas and preparation thereof, and discloses a high-stability chlorine-containing disinfectant formula and a preparation method thereof.A plurality of components such as 1-hydroxyethylidene-1, 1-diphosphonic acid, ethylenediamine tetramethylene phosphonic acid sodium salt, sodium silicate, sodium carbonate, sodium chlorate, sodium chloride and sodium hydroxide are added into the disinfectant as a composite inhibitor to reduce decomposition reaction and disproportionation reaction of sodium hypochlorite in the disinfectant, so that the service life of the disinfectant is guaranteed; by compounding multiple components, the stability of the system is guaranteed, and the storage time of the stock solution and the diluent is prolonged. The preparation method of the disinfectant provided by the invention is simple to operate, and the stability and the sterilization effect of the disinfectant are greatly improved through different adding sequences, limited reaction time and selection of specific pH value parameters.