30results about How to "Low content of impurity ions" patented technology

The invention relates to high-purity iron phosphate used for producing a lithium ion battery positive-pole material and a preparation method thereof. The preparation method is characterized by comprising the following steps: taking ferrous salt and carbonate as raw materials; reacting to generate intermediate product ferrous carbonate precipitation, wherein, the ferrous carbonate is easy to filter, and the foreign ions are easy to wash; filtering and recovering ammonium sulfate; dissolving the ferrous carbonate precipitation; adding oxidant for oxidizing; regulating the pH value of the solution; heating and preserving the temperature for a certain time to obtain the iron phosphate precipitation; filtering, drying and precipitating to obtain the high-purity iron phosphate; and mixing and calcining the high-purity iron phosphate, the lithium source and the carbon source to obtain the lithium ion battery positive-pole material with excellent electrochemistrical performance. By using the method provided by the invention, the impurity content in the iron phosphate is effectively lowered, the process time is shortened, the energy consumption is reduced, and the cost and the consumption of the raw materials are lowered; and the filter liquor is easy to recover, and the production cost is very low, thus being beneficial for large-scale production in scaled industry.

The invention discloses hydroxyl silicone oil and a continuous preparation method thereof.The method includes the following steps of firstly, adding hexamethyl cyclotrisiloxane, solvent and water into a mixing kettle to be evenly stirred and mixed, and transferring the mixture into a sulfuration bed filled with a catalyst to sufficiently react; secondly, conducting adsorption filtering, ultrafiltration membrane filtering, normal-pressure devolatiligation and reduced-pressure devolatiligation to obtain the hydroxyl silicone oil, recovering solvent and unreacted low-molecular compounds, detecting the contents of all components and then conducting recycling.The method is high in efficiency, low in energy consumption, free of pollutant emission, clean, sanitary and low in production cost, solvent and unreacted low-molecular compounds used in reaction can enter a reaction system to be recycled after the contents of all the components are detected, and the method is free of pollutant emission, green and environmentally friendly.The hydroxyl silicone oil is low in viscosity, high in product purity, low in annulus content, low in impurity ion content and high in storage stability.

The invention relates to flame retardant rigid polyisocyanurate foam and a preparation method thereof. The flame retardant rigid polyisocyanurate foam is prepared from the following components in parts by weight: 150-170 parts of polyisocyanate, 5-8 parts of polyether polyol, 15-20 parts of flame retardant, 2-3 parts of catalyst, 1-2 parts of stabilizer, and 15-20 parts of foaming agent. The flameretardant is prepared by mixing a nitrogen-containing flame retardant and a phosphorus-containing flame retardant at the mass ratio of 1:1. The preparation method comprises the following steps: S1, mixing an additive; and S2, preparing rigid polyurethane foam. The flame retardant rigid polyisocyanurate foam has the advantages of being good in flame retardant effect, high in rigid foam performanceand suitable for industrial production.

The invention discloses a polycarboxylic acid for electrolyte as well as a preparation method and application thereof. The polycarboxylic acid for the electrolyte has a structural general formula, wherein R1, R2, R3 and R5 are hydrogen radicals and alkyl radicals; n is an integer from 2 to 12; m is an integer from 1 to 3; and R1, R2, R3 and R5 are same or different to each other. The ammonium salt of the polycarboxylic acid for the electrolyte has the advantages of high solubility in a menstruum, high conductivity, excellent high-low temperature resistance, long service life, and the like; and in addition, the invention has the advantages of simple preparation method, high yield, low foreign ion content and suitability for industrial large-scale production.

The invention relates to the field of waste sulfuric acid treatment processes, in particular to a waste sulfuric acid recovery treatment method, which comprises the following steps: diluting waste sulfuric acid, adding a catalyst, carrying out ultrasonic treatment and stirring treatment for 5-20 hours under an illumination condition, filtering, adding adsorption resin into filtrate, adsorbing for 20-25 hours, filtering, and adjusting the concentration to obtain recovered sulfuric acid, by utilizing the catalytic degradation and adsorption effects of the catalyst and the resin, anthraquinone dye and other organic impurities in the waste sulfuric acid can be purified, the chromaticity is reduced, the waste sulfuric acid can be used as a crude chemical raw material after being recycled, the treatment cost of the waste sulfuric acid is reduced, and sulfuric acid resources are fully utilized.

The invention relates to the technical field of lithium battery cathode materials, and provides a preparation method of high-purity manganese sulfate, which comprises the following steps: removing heavy metal ions in a crude manganese salt solution, and mixing the obtained liquid-phase product with bicarbonate to precipitate calcium, magnesium and manganese ions, thereby obtaining a crude manganese carbonate solid; dispersing the crude manganese carbonate solid in water, and introducing carbon dioxide into the dispersion liquid to obtain a refined manganese carbonate solid; dissolving the refined manganese carbonate solid in dilute sulfuric acid, and then concentrating and crystallizing to obtain high-purity manganese sulfate. According to the method, manganese salt is converted into manganese carbonate by controlling reaction conditions, calcium carbonate and magnesium carbonate precipitated along with manganese carbonate are converted into soluble bicarbonate by introducing carbon dioxide, then calcium and magnesium ions are removed, and high-purity manganese sulfate can be conveniently obtained through sulfuric acid redissolution and crystallization. The method provided by the invention is simple in steps and low in cost, and the content of impurity ions in the obtained high-purity manganese sulfate is extremely low.

The present invention relates to a new type of nano powder surface treatment method, which is characterized in that it includes using cheap technical water glass as raw material, adding different types of surfactants into the solution system by adopting micellar method to control the precipitation reaction The microenvironment makes the generated precipitation particles be back-wrapped, maintains a high degree of dispersion of the precipitation particles, prevents the aggregation and growth phenomenon between the particles, and prepares high-purity, spherical nanoparticle materials. A new nano-powder surface treatment method overcomes the hard agglomeration and uneven particle distribution that tend to occur when preparing nano-powders by traditional methods. It is an effective new method for preparing nano-powder materials with high purity, good shape and narrow particle size distribution.