61results about How to "Low fluorine content" patented technology

The invention relates to a method for separating scheelite from fluorite and belongs to the technical field of mineral dressing of metal mines. The method comprises the following steps of: preparing ore pulp from tungsten secondary concentrate ore containing 30 to 60 weight percent of tungsten trioxide; carrying out two stages of separation by adopting shaking tables; then making middlings of a first-stage shaking table enter a second-stage shaking table to be separated so as to produce special grade white tungsten concentrate ore products containing over 70 weight percent of tungsten trioxide; concentrating the middlings and tailings, which are separated by the shaking tables, to 50 to 60 weight percent in a centralizing mode, then adding water glass and TN into the concentrated middlings and tailings, and uniformly stirring the mixture in a stirring barrel for flotation; diluting flotation pulp to 20 to 30 weight percent, regulating the pH of the diluted flotation pulp to 9 to 10, and adding an inhibitor KJ and a collector YY to produce white tungsten concentrate ore containing over 65 weight percent of tungsten trioxide; and further carrying out flotation on the flotation tailings to obtain fluorite powder ore containing over 85 percent of calcium fluoride. The method has the advantages of high mineral dressing index, simple process, low production cost, environmental protection and capability of better solving the environmental problems of ammonium paratungstate manufacturing enterprises, which are caused by high fluorine content of raw materials.

A process for defluorinating anhydrous hydrogen chloride as by-product in the technology for preparing hydrogen contained fluorchlorohydrocarbon features that the hydrogen chloride is pre-activated and then defluorinated in serially or parallelly connected defluorinating towers by adsorption at -10-80 deg.C and 0.1-20 MPa. The alumina is used as main component of defluorinating agent. Its advantage is high defluorinating effect (less than 10 ppm).

The invention provides a method of leaching valuable metal from a waste lithium ion battery and synchronously conducting defluorination. The method specifically comprises the steps that the waste lithium ion battery is pretreated, electrode powder materials are obtained, the electrode powder materials, water and concentrated sulfuric acid are evenly mixed, curing treatment is conducted, the temperature of the curing treatment is controlled to range from 50 DEG C to 200 DEG C, the time of the curing treatment is controlled to range from 1.0h to 24.0h, a leaching agent is added to a cured material to conduct leaching operation after the curing treatment is accomplished, filtering operation is conducted after leaching operation is accomplished, and low-fluorine-content valuable metal leachateis obtained. According to the method, removal of fluorine in the electrode powder and leaching operation of the valuable metal are organically combined, the curing defluorination step is added beforeacid pickling operation of the electrode powder is conducted, namely, part of concentrated sulfuric acid is added to the electrode powder to conduct curing defluorination, then part of concentrated sulfuric acid is supplemented and added to the defluorinated electrode powder to conduct leaching operation, and the two processes are closely connected. Compared with a conventional acid pickling technology, the method has the advantages that the acid consumption is not increased, the technological cost is low, the operability is high, the fluorine content of the obtained valuable metal leachate is low, and the industrial production is easily achieved.

The present invention discloses an aluminium-silica type refined pre-smelting slag, which is provided for solving the problems of prominent foreign material quality problem and the large fluctuation during a high-grade bearing steel producing process, low continuous casting success rate (only about 30%) during a middle (high) sulfur structure steel producing process, and high unqualified rate of the sulfide. The aluminium-silica type refined pre-smelting slag comprises the following components, by weight, 10.0-30.0% of waste glass, 25.0-45.0% of fly ash, 35.0-55.0% of 65% waste high alumina brick and 1.0-3.0% of a fluxing agent. The aluminium-silica type refined pre-smelting slag has the following advantages that: (1) the slag system is stable, and the slag adjusting process is not required; (2) the level for controling the non-metallic foreign material in the adsorption steel is high; (3) the slag does not agglomerate, the melting and slaggling time is short (less than or equal to 2 minutes); (4) the yield of the sulfur of the middle (high) sulfur structure steel during the later stage sulfur adjusting process is stable; (4) the product does not powder, and the shelf life is more than six months.

The invention provides a fluorine absorption system used for wet-process phosphoric acid. The system comprises a Venturi scrubbing device, a primary washing device, a pipe washing device, a secondarywashing device and a tertiary washing device which are arranged in sequence. According to the fluorine absorption system used for the wet-process phosphoric acid, waste gas containing fluorine passesthrough the Venturi scrubbing device, the primary washing device, the pipe washing device, the secondary washing device and the tertiary washing device in sequence for multi-stage washing, the washingdevices are provided with circulating tanks respectively, circulating fluid in the Venturi circulating tank and the primary washing tower circulating tank is continuously pumped out to enter a firstplate-and-frame filter press and a second plate-and-frame filter press, silica gel precipitation in the fluorine absorption system is removed, and the blocking frequency is reduced. The recycled watersupplement path is changed, the temperature of exhaust and the concentration of the circulating fluid are reduced, and therefore, the fluosilicic acid absorbing efficiency is improved.

The invention discloses a high-molecular compound and a preparation method thereof, particularly relates to a fluorinated polymer with extremely low fluorine content and a high-stability hydrophobic surface and a preparation method thereof. In the invention, crystalline long-chain alkyl methacrylate is introduced in the middle of a polymethylmethacrylate-b-polyperfluorooctylethyl methacrylate block polymer. The preparation method comprises the steps of preparing a PMMAk-Br macroinitiator and a PMMAk-b-PODMAm-Br macroinitiator stage by stage and then preparing a fluorinated block copolymer. The compound prepared by the invention can improve the surface hydrophobic and lipophobic properties, the surface fluorine-contained component enrichment and the environment surface stability of a polymer. The preparation method has mild reaction conditions, is easy to operate, moreover, the contents of all the components used in the method can be regulated and controlled. The invention has wide application value.

The invention relates to a method for producing lanthanum-enriched rare earth chloride by using bastnaesite as a raw material. The method comprises the following steps of: mixing the bastnaesite and sodium hydroxide and then roasting, carrying out sodium hydroxide alkali conversion on the bastnaesite to remove fluorine, washing the bastnaesite subjected to alkali conversion with water, and carrying out hydrochloric acid optimum solution to obtain lanthanum-enriched rare earth chloride liquid. In the alkali conversion process, the ratio of NaOH to REO (Rare Earth Oxide) in the bastnaesite is (0.10-0.40):1, the alkali conversion is carried out at 300-600 DEG C, and then the bastnaesite subjected to the alkali conversion is washed with water 3-8 times of the bastnaesite by weight proportion.In the optimum solution process, the weight ratio of 31% of industrial hydrochloric acid by weight to the REO in the bastnaesite is (1-1.5):1. In the alkali conversion process, the fluorine in the enriched lanthanum is preferentially subjected to the alkali conversion to obtain lanthanum-enriched hydroxide which is dissolved with acid, acid-soluble lanthanum-enriched rare earth is dissolved in a solution, and cerium is reserved in slag with large amount of fluorine, therefore, the purpose of separating the cerium and non-cerium can be achieved easily. In the whole process, the step of solid-liquid separation is reduced, the consumption of auxiliary materials is lowered, the yield per unit of equipment and the yield of rare earth are improved, and the production process has less pollution.

The invention discloses a preparation method of a low-fluorine high-purity tantalum pentoxide optical coating material, and particularly relates to the technical field of tantalum metal oxide preparation, which comprises the following steps: dissolving metal tantalum in a mixed acid of hydrofluoric acid and nitric acid, extracting and purifying to obtain a high-purity tantalum liquid, introducingthe high-purity tantalum liquid into a neutralization precipitation tank, adding liquid ammonia into the high-purity tantalum liquid at the same time, introducing a solution containing tantalum hydroxide precipitate into a filter press after the tantalum hydroxide precipitate appears, adding ammonia-containing hot pure water at the same time, then obtaining tantalum hydroxide, and then repeatedlyadding tantalum hydroxide into the filtering process for multiple times. According to the method, tantalum pentoxide is heated through electron beams, the purpose of heating calcination can be achieved without high temperature, grain distribution is uniform, the crystal system structure is more ideal, meanwhile, ammonia-containing hot pure water is repeatedly used for assisting the filtering process, it is guaranteed that the effect of removing fluorine in the tantalum hydroxide solution is more ideal and sufficient, and the fluorine content in the product is greatly reduced.

The invention discloses an instant krill paste and a preparation method for the instant krill paste. The instant shrimp paste consists of 75-90 parts of krill flesh, 3-8 parts of water, 3-8 parts of mycose, 3-8 parts of potato starch, 0.8-1.6 parts of table salt and 0.2-0.6 parts of aginomoto. According to the instant krill paste, by taking the shelled krill flesh as a raw material, not only is the crisp mouth feeling of the krill paste guaranteed, but also the fluorine content of krill products is reduced by removing parts including krill shells with relatively high fluorine content, so thatthe fluorine content of the product is reduced by about 62%; and the type of the krill products is broadened, and a new way is opened to developing commercial value of krill.

The invention discloses a polyurethane heat-dissipating dustproof coating and a preparation method and application thereof. Raw materials of the polyurethane heat-dissipating dustproof coating include a component A and a component B. The component A comprises the following ingredient in parts by weight: 16-75 parts of isocyanate; the component B comprises the following ingredients in parts by weight: 1-3 parts of polytetrafluoroethylene, 40-100 parts of polyhydric alcohols and 300-600 parts of a solvent; the total parts by weight of the isocyanate and the polyhydric alcohols is 90-150; the average particle size of the polytetrafluoroethylene is 120-800 nm; the polyhydric alcohols comprise fluorine-containing dihydric alcohols; and on the basis of the total weight of the polyhydric alcohols, the weight percentage of the fluorine-containing dihydric alcohols is 15-30wt%. By the polyurethane heat-dissipating dustproof coating and the preparation method and application thereof, dust accumulation is reduced, and the problems that the surface heat resistance of a heat sink and the like is increased, the heat conduction coefficient is reduced and the heat transfer efficiency is reduced due to dust blockage are solved.