3788 results about "Sulfide compound" patented technology

The invention relates to a method for preparing lithium sulfide, which comprises the following steps: respectively dissolving a sulfur source compound and a lithium source compound in alcohol under the protection of inert atmosphere, and then mixing the two alcohol solutions for double decomposition reaction to generate a lithium sulfide suspension; and then carrying out evaporative crystallization, supercritical fluid washing, centrifugal separation and freeze drying treatment to obtain a lithium sulfide product. The purity of the lithium sulfide prepared through the method can reach 99.9% or above, the lithium sulfide can be used as a positive electrode material of a lithium-sulfur battery or a raw material of a sulfide solid electrolyte in an all-solid-state battery, and the method is low in energy consumption, conforms to the concept of green chemistry and is suitable for large-scale industrial production.

The invention relates to a polymer binder for a sulfide solid-state battery as well as a preparation method and application of the polymer binder. The binding agent is formed by copolymerizing vinyl triethoxy silane, 4-vinyl phenylboronic acid lithium and styrene. Silane groups are introduced, the interface adhesiveness with sulfide electrolyte is enhanced through the coupling effect of the silane groups, meanwhile, water in a system is consumed through a condensation reaction, and the water content of an electrolyte membrane is reduced; 4-vinyl phenylboronic acid lithium provides dissociation lithium ions, the ionic conductivity of the binder is improved, and the negative influence on the conductivity of sulfide electrolyte is reduced; the styrene group improves the solubility of the binder in a non-polar solvent. The binder can be dissolved in solvents such as toluene, xylene and the like, and is mixed with sulfide electrolyte to form a film through a wet coating process, and the process compatibility is high. The binder disclosed by the invention has the characteristics of high cohesiveness, ionic conductivity and low water content, and the interface stability and electrochemical performance of the sulfide solid-state battery can be remarkably improved.

The invention relates to the technical field of batteries, in particular to a solid electrolyte material and a preparation method thereof, a solid electrolyte membrane and a battery. The solid electrolyte material has a core-shell structure, the core-shell structure comprises an inner core and a coating layer arranged on the surface of the inner core, the inner core comprises a sulfide electrolyte, and the coating layer comprises an amide compound. According to the solid electrolyte material disclosed by the invention, the coating layer containing the amide compound is arranged on the surface of the sulfide electrolyte, so that the air stability of the solid electrolyte material can be effectively improved, and meanwhile, the solid electrolyte material is ensured to have proper conductivity without influencing the charge-discharge performance of a battery.

The invention discloses high-purity lithium sulfide as well as a preparation method and application thereof. The preparation method comprises the step that lithium hydride, lithium hydroxide and a sulfur source are subjected to a heating reaction in a dry inert atmosphere, and the high-purity lithium sulfide is obtained. The molar ratio of lithium hydride to lithium hydroxide is X: (10-X), and X is 1-6. The invention also discloses the prepared high-purity lithium sulfide and application of the high-purity lithium sulfide in preparation of sulfide solid electrolyte. Lithium hydroxide and lithium hydride are mixed to serve as a lithium source in lithium sulfide preparation, the lithium hydroxide quickly and uniformly reaches the reaction temperature by means of the characteristic that the lithium hydride reacts with a sulfur source to release heat and produce gas, the lithium hydride reacts to produce gas, meanwhile, discharging of product water vapor is facilitated, and oxygen in the environment is isolated; and hardening and generation of a side reaction product lithium sulfate are prevented, the conversion rate of lithium hydroxide to lithium sulfide is improved, and the raw material and process cost for preparing lithium sulfide is remarkably reduced.

The invention discloses a single-ion conductor polymer, a ternary composite binder solution, high-solid-content sulfide electrolyte slurry and a wet film forming method and application thereof, and belongs to the technical field of all-solid-state lithium batteries. The key technical problems in the wet membrane preparation of the sulfide electrolyte are solved through an innovative solvent-binder synergistic system, and the method specifically comprises the steps that 1, through the synergistic effect of a non-polar solvent and a weak-polar solvent, low-viscosity coating of high-solid-content slurry is achieved while the chemical stability of the sulfide electrolyte is guaranteed; 2, a poly (lithium styrenesulfonate-butyl acrylate), styrene butadiene rubber and polyisobutene ternary composite binder is designed, a lithium ion transmission channel is provided through a lithium sulfonate group, a benzene ring structure in the styrene butadiene rubber enhances the mechanical strength, long-chain alkane in the polyisobutene improves the interface adhesive force, and the mechanical strength is improved; the three components cooperate to realize balance of mechanical and electrochemical properties of the electrolyte membrane, so that the prepared electrolyte membrane has low porosity, high ionic conductivity and mechanical strength.

The invention discloses a preparation method and application of a sulfide solid electrolyte membrane based on a gradient polymer / ionic liquid composite binder, and an all-solid-state battery, and belongs to the technical field of all-solid-state batteries. The method comprises the following steps: firstly coating a polymer / ionic liquid / sulfide electrolyte composite layer through a gradient coating process, filling particle gaps under low pressure by utilizing the plasticizing effect of ionic liquid, and reducing the porosity of an interface; and then coating a polymer / sulfide electrolyte surface layer to provide mechanical support and inhibit side reaction of the electrode. According to the design, the electrolyte membrane still keeps high ionic conductivity under the working pressure of a commercial power battery module, and the interface impedance is reduced compared with that of a traditional homogeneous membrane. Through the innovative gradient structure and material combination, the ion transmission bottleneck of the sulfide electrolyte under the low-pressure condition is solved, excellent interface stability and process compatibility are achieved, and a key technical scheme is provided for all-solid-state battery industrialization.

Preparation of anhydrous lithium sulfide (Li2S) purified suitably for applications in advanced batteries, and, in particular, for synthesis of solid electrolytes based on Li2S, including sulfide solid electrolytes of the type that may be described as crystalline (e.g., polycrystalline), amorphous (e.g., glass) and combinations thereof, such as sulfide glass-ceramic solid electrolyte materials.

The invention provides a positive pole piece, a preparation method thereof and a sulfide all-solid-state battery. The positive pole piece comprises a positive current collector and a positive material layer arranged on the surface of the positive current collector, the positive electrode material layer comprises a modified positive electrode active material, an antioxidant, a sulfide electrolyte material, a conductive agent and a positive electrode binder, the modified positive electrode active material comprises an inner core and an oxide coating layer arranged on the surface of the inner core, and the inner core is a lithium-containing positive electrode active material. When the positive electrode plate containing the antioxidant and the modified positive electrode active material provided by the invention is applied to the sulfide all-solid-state battery, the synergistic effect of the antioxidant and the modified positive electrode active material can be exerted, so that the rate capability and the cycling stability of the sulfide all-solid-state battery are improved.

The invention provides a modified lithium sulfide solid electrolyte, a sulfide solid electrolyte, a preparation method thereof and a battery, and relates to the technical field of solid electrolyte materials. The preparation method of the sulfide solid electrolyte is different from a traditional doping technology, the high-stability sulfide solid electrolyte is prepared mainly through modification of lithium sulfide, the comprehensive performance of the sulfide solid electrolyte is improved, the ionic conductivity and chemical stability of the sulfide solid electrolyte are improved, and the service life of the sulfide solid electrolyte is prolonged. And the mechanical strength and the crack resistance are also obviously enhanced. The preparation method disclosed by the invention is simple, does not need to be carried out at high temperature, and does not need to use expensive raw materials and complex processes, so that the production cost is reduced, the application range of the sulfide solid electrolyte is expanded, and large-scale production and application of the sulfide solid electrolyte are favorably realized.

The invention discloses a desulfurizing tower and a desulfurizing method based on enhanced absorption of flat sheet membrane internals. The desulfurizing tower comprises a desulfurizing tower body, and a liquid distributor, the flat sheet membrane internals and fractal internals which are sequentially arranged in the desulfurizing tower body from top to bottom, according to the invention, high-concentration sulfur-containing gas is subjected to rapid pre-desulfurization at the tower bottom by utilizing the high turbulence characteristic of the fractal internals, so that the sulfide concentration can be instantly reduced, and the gas flow distribution is optimized; and the pre-desulfurized gas then enters a high-efficiency fine desulfurization area formed by the flat sheet membrane internals. According to the flat sheet membrane internal part, a plurality of vertically arranged flat sheets are utilized to form a fixed gas flowing channel, so that transverse movement of gas molecules is limited, and gas distribution is more uniform. And meanwhile, a layer of uniform and continuous absorbent liquid film is formed on the surface of the flat plate, so that the gas-liquid contact area is remarkably increased, and high efficiency and low energy consumption are achieved through full countercurrent contact and efficient gas-liquid mass transfer of gas and the absorbent liquid film under extremely low pressure drop.

The invention relates to the technical field of all-solid-state batteries, in particular to a halide sulfide double-layer coated positive electrode material and a preparation method and application thereof. The halide sulfide double-layer coated positive electrode material comprises a positive electrode material substrate, and a halide electrolyte coating layer and a sulfide electrolyte coating layer which sequentially coat the positive electrode material substrate. The halide electrolyte coating layer is located in the middle layer, compatibility with a positive electrode interface can be achieved by means of high oxidation resistance of the halide electrolyte coating layer, and the problem of the positive electrode interface occurring in sulfide electrolyte oxygenolysis is solved. The sulfide electrolyte coating layer is located on the outermost layer, air stability is excellent, processing in a dry environment can be met, and the problems that halide electrolyte is poor in chemical stability, cannot be processed and manufactured in an external environment and is high in density are solved. The halide sulfide double-layer coated positive electrode material has high interface stability and good chemical stability.

The invention relates to the technical field of new energy battery materials, in particular to a surface-coated sulfide solid electrolyte as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing and stirring a sulfide solid electrolyte and a first solvent to obtain a first mixed solution; mixing and stirring nanoparticles with oxygen-containing functional groups and a second solvent to obtain a second mixed solution; adding the second mixed solution into the first mixed solution, and stirring to obtain a third mixed solution; and carrying out vacuum drying on the third mixed solution to obtain the surface-coated sulfide solid electrolyte. The sulfide solid electrolyte is subjected to surface particle coating through simple mixing and vacuum drying, oxygen-containing functional groups are attached to the surfaces of the particles, so that the material is more oxygen-loving, the air stability of the sulfide solid electrolyte is improved, and the material still keeps high ionic conductivity and has good electrochemical performance. And moreover, the machining process is reduced, the machining cost is reduced, and the practical application value is higher.

The present disclosure belongs to the technical field of all-solid-state batteries. Provided are a sulfide solid electrolyte membrane and a preparation method therefore, and an all-solid-state alkali metal ion battery. The sulfide solid electrolyte membrane is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing a polymer coating is [EmMnSo]CαOβSγHδNζEa.

The invention discloses a preparation method and application of a composite sulfur positive electrode packaged by a sulfide-halide composite electrolyte spherical shell. The composite sulfur positive electrode packaged by the sulfide-halide composite electrolyte spherical shell provided by the invention has a core-shell structure, the inner core is a sulfur-carbon composite material, and the outer layer is a sulfide-halide composite electrolyte shell; the sulfur volume change effect in the charging and discharging process can be effectively relieved, uniform stress distribution and effective contact in the composite positive electrode are ensured, and the utilization rate of positive electrode active substances and the overall energy density of the battery are improved. Meanwhile, the composite sulfur positive electrode provided by the invention has high ionic conductivity at room temperature, can significantly improve the reaction kinetics of the positive electrode and improve the capacity and rate capability of the battery, can be used for assembling and preparing a solid-state lithium-sulfur battery, has good safety performance and high energy density, and has a wide application prospect.

The invention discloses a sulfide-based composite solid-state electrolyte, a preparation method thereof and a lithium metal solid-state battery, sulfide is subjected to specific bifunctional surface grafting modification by using a silane coupling reagent with sulfydryl and epoxy bonds, then the sulfide is introduced into a polymer precursor liquid, and the sulfide-based composite solid-state electrolyte is prepared through light-heat curing reaction synergy. A flexible and rigid cross-linked network is formed, the sulfide-based composite solid-state electrolyte with high ionic conductivity and high mechanical strength is obtained, the interface stability of the sulfide-based composite solid-state electrolyte in the charge-discharge process is ensured, for example, the sulfide-based composite solid-state electrolyte in the embodiment 1 has high ionic conductivity (3.81 mS / cm), and the interface stability of the sulfide-based composite solid-state electrolyte in the embodiment 2 is ensured. The lithium-lithium symmetric battery prepared by the method has the advantages of excellent flexibility, high tensile strength (7.9 Mpa) and wide electrochemical window (5.1 V), the lithium-lithium symmetric battery can stably circulate for 2000h, and the whole battery can stably circulate for 2000 circles at the room temperature at the rate of 4C, so that the lithium-lithium symmetric battery has great industrial application value.

The invention provides a surface-modified sulfide electrolyte and a preparation method thereof, and an all-solid-state battery, the surface-modified sulfide electrolyte comprises a sulfide electrolyte and a modification layer coated on the surface of the sulfide electrolyte, the chemical general formula of the modification layer is LiaMbNcXd, 0 < = a < = 3, 0 < = b < = 1, 0 < = c < = 1, 0 < = d < = 6, and 0 < = c < = 1. M is at least one element of magnesium, aluminum, calcium, iron, zirconium, niobium, tantalum, tungsten, gadolinium, yttrium, indium, hafnium, lanthanum and ytterbium, and X is at least one element of oxygen, sulfur, fluorine, chlorine, bromine and iodine. According to the surface-modified sulfide electrolyte, the modification layer with high ionic conductivity and high oxidation potential is coated outside the sulfide electrolyte, so that when the surface-modified sulfide electrolyte is applied to a positive electrode of an all-solid-state battery, the modification layer can improve the oxidation potential of the electrolyte on the premise of not reducing the ionic conductivity of the electrolyte; the effects of improving the interface stability between the positive electrode active material and the sulfide electrolyte and further improving the cycle performance of the battery are achieved.

A supercapacitor including a negative electrode, a positive electrode, an electrolyte, and a separator. The separator is between the negative electrode and the positive electrode, and the electrolyte is present in and on the separator. The negative electrode and the positive electrode include a carbon material selected from a poly-anthraquinone sulfide activated carbon material and a poly-anthraquinone sulfide reduced activated carbon material.

To provide an in-situ electrochemical passivation and repair method for a solid-state lithium battery.SOLUTION: A sulfide-based solid-state battery is discharged to a specific lithiation degree according to a specific discharge mode under low current density, so that in-situ electrochemical passivation and / or repair of the battery are / is realized. Through the electrochemical reduction method, the interface of the sulfide-based solid-state battery can be passivated and stabilized, and the sulfide electrolyte is prevented from being continuously decomposed in the charging and discharging process, so that the sulfide solid-state electrolyte can be matched with an oxide positive electrode material with relatively high operating voltage; and an oxidation product generated by decomposition in the cycle process is converted into a lithium-rich reduction product with ion conductivity again, so that the activation and repair effects are achieved, and the battery has more excellent cycle stability.SELECTED DRAWING: Figure 13

The invention provides a method for preparing an iron-chromium electrolyte and electronic-grade ferrous chloride by using a stainless steel waste liquid. The method comprises the following steps: firstly, adding elemental iron and / or elemental chromium into the stainless steel waste liquid to obtain a chromium-containing ferrous chloride solution; then, sulfide is added, and nickel is removed; adding iron powder to increase the pH value to obtain chromium hydroxide precipitate and a ferrous chloride solution; dissolving chromic hydroxide in hydrochloric acid to obtain a chromic chloride solution; purifying the ferrous chloride solution to obtain an electronic-grade ferrous chloride crystal; and finally, adding a chromium chloride solution, the electronic-grade ferrous chloride crystal and hydrochloric acid according to a certain proportion, and stirring and mixing to obtain the iron-chromium electrolyte. The ferrous chloride prepared by the steps is relatively high in purity and less in waste; meanwhile, the prepared electrolyte is good in electrical property, low in attenuation rate and low in cost, the purpose of comprehensive recycling of resources is achieved, and the general trend of technical improvement is met.

The invention belongs to the technical field of phosphoric acid purification, and particularly relates to a removing agent and a removing method for heavy metal cadmium in phosphoric acid. The removing agent comprises a solvent, a thiophosphoric acid trapping agent A and a thiophosphoric acid trapping agent B, wherein the thiophosphoric acid trapping agent A and the thiophosphoric acid trapping agent B are dispersed in the solvent; the thiophosphoric acid trapping agent A and the thiophosphoric acid trapping agent B are different types of thiophosphoric acid trapping agents and are respectively and independently selected from one of alkyl dithiophosphoric acid or salts thereof, phenolic dithiophosphoric acid or salts thereof and amino dithiophosphoric acid or salts thereof; and at least one hydrocarbyl dithiophosphoric acid or salt thereof is selected; the salt is sodium salt or ammonium salt; the solvent is water or an alkaline aqueous solution. According to the method, a composition of a dithiophosphoric acid trapping agent is used as a removing agent for cadmium in wet-process phosphoric acid, a precipitate which is insoluble in a strongly acidic water phase is generated after reaction, and phosphoric acid cadmium removal is realized after filtration. Compared with a conventional sulfide precipitation method, the method provided by the invention has the advantages of less cadmium residue in phosphoric acid and less pollution.

The invention discloses an iodine compound coated sulfide solid electrolyte as well as a preparation method and application thereof, and relates to the technical field of batteries. The preparation method comprises the following steps: mixing and ball-milling coating liquid and sulfide solid electrolyte powder to obtain a mixture; carrying out solid-liquid separation on the mixture to obtain a solid, washing the solid, drying, and carrying out heat treatment to obtain a sulfide solid electrolyte coated with an iodine compound on the surface; wherein the coating liquid comprises the following components in percentage by mass: 0.1-10% of an iodine compound coating agent and 90-99.9% of a coating auxiliary agent. The surface of the particle can be modified, the dispersion condition of the sulfide electrolyte is improved, and the reaction activity between the sulfide electrolyte and the iodine compound is regulated and controlled; and shear force is provided through ball milling, and uniform liquid phase coating can be realized, so that the forming process of the coating layer is optimized, the thickness and compactness of the coating layer are regulated and controlled, and the interface stability of the sulfide solid electrolyte and the metal lithium negative electrode is improved.

The invention discloses a mixed ion conductor layer for a lithium metal negative electrode, a preparation method of the mixed ion conductor layer and an all-solid-state battery, and belongs to the technical field of sulfide all-solid-state batteries. The preparation method comprises the following steps: synthesizing a sulfide electrolyte 70 (0.75 Li2S-0.25 P2S5)-30LiI through a liquid phase, introducing graphene oxide and a lithium salt precursor 2, 5-dihydroxy-1, 4-benzene diphosphate in the electrolyte preparation process, and carrying out heat treatment and pressing to obtain a mixed ion conductor layer; the graphene oxide can isolate the sulfide electrolyte layer from the lithium metal negative electrode, interface reaction is avoided, and a special porous and interlayer structure provides a transverse growth space for lithium metal deposition. And meanwhile, the lithium diphosphate-based MOF among the graphene layers ensures the rapid movement of lithium ions, enhances the bulk diffusion of lithium at the negative electrode end, reduces the local current density, plays a role in dredging the distribution of the lithium ions, and remarkably prolongs the cycle life of the sulfide all-solid-state battery.

The invention provides a composite sulfide solid electrolyte, a preparation method thereof and a lithium ion battery. The composite sulfide solid-state electrolyte comprises a sulfide solid-state electrolyte matrix and a composite layer coating the surface of the sulfide solid-state electrolyte matrix, the composite layer comprises an interface reaction layer and a coating layer from inside to outside, the coating layer comprises a halide material, and the interface reaction layer comprises an interface reactant obtained after the halide material and the surface of the sulfide solid electrolyte matrix are subjected to an interface reaction. According to the invention, under the action of the specific surface composite layer, the electrochemical window and mechanical property of the sulfide solid electrolyte are widened, the mechanical stability and electrochemical stability of the sulfide solid electrolyte and a positive electrode material are improved, and the interface reaction of the sulfide solid electrolyte is further inhibited.

The invention relates to the technical field of researching or analyzing materials by testing chemical or physical properties of materials, in particular to an intelligent analysis method for corrosivity of sulfide molecules in transformer oil. The influence of the oil environment on the adsorption energy is simulated and corrected in combination with molecular dynamics, a microscopic parameter database is constructed, and a corrosion risk grade classification rule and a generation rate prediction model are established. Oil data are collected in real time and input into the model to output a dynamic risk level, and a circulation rate adjusting or corrosion inhibitor adding instruction is triggered. Model parameters are regularly corrected by combining a closed-loop feedback mechanism, and a microscopic database is expanded, so that transfer learning prediction of unknown sulfide corrosion behaviors is realized. According to the method, the limitation of an existing single experiment condition is broken through, the relevance between a microcosmic molecular mechanism and a macroscopic corrosion behavior is dynamically analyzed, and the prediction precision under the multi-factor coupling effect is improved.

The invention relates to the field of wastewater treatment, and discloses a method for treating nitrogen-containing wastewater based on sulfur autotrophic DNRA and anaerobic ammonia oxidation, which comprises the following steps: firstly, introducing nitrogen-containing wastewater into an Anammox reactor, inoculating granular sludge taken from a secondary sedimentation tank of a sewage treatment plant into the Anammox reactor, carrying out anaerobic ammonia oxidation reaction, controlling hydraulic retention time, and carrying out anaerobic ammonia oxidation treatment on the sludge; the method comprises the following steps: pumping effluent and sulfur source inlet water into an sDNRA reactor together, inoculating ordered batch sDNRA sludge into the sDNRA reactor, performing DNRA action under sulfide driving in a stirring state, and controlling hydraulic retention time to realize automatic effluent. According to the method disclosed by the invention, a carbon source does not need to be added, byproducts generated along with complex carbon metabolism can be effectively reduced, the cost can be effectively reduced while secondary pollution is avoided, the total nitrogen removal rate of the system can be successfully improved, and the generation of greenhouse gas N2O is reduced.

The present invention relates to a composite sulfide electrolyte, and a preparation method therefor and a use thereof. The composite sulfide electrolyte has a three-dimensional crosslinked structure formed by connecting a sulfide electrolyte and a dynamic bond-containing crosslinked polymer by means of chemical bonds. The polymer contains a sulfur element and exhibits relatively higher stability when interacting with the sulfide electrolyte, the chemical crosslinking between the sulfide electrolyte and the dynamic bond-containing crosslinked polymer is formed by means of multiple chemical bonds, such as a disulfide bond and an amido bond, and a strong binding force and self-healing function are provided, in order to simultaneously solve the problems of interfacial delamination and cracking caused by mechanical stress inside the sulfide electrolyte. When applied in an all-solid-state battery, the composite sulfide electrolyte can improve the limiting current density and cycle stability of the all-solid-state battery.

The invention belongs to the technical field of petroleum processing, and particularly relates to a catalyst and a preparation method and application thereof. The raw materials of the catalyst comprise a metal active component, a carrier and an auxiliary agent, the metal active component is sulfides of Mo and Ni elements, the carrier is spherical gamma-Al2O3 of 0.5-1 mm, and the auxiliary agent is P; the carrier is modified by using the metal active component and the auxiliary agent to serve as the catalyst. The high-activity catalyst is synthesized by adopting the strategy of changing the roasting temperature, adding the additive for doping modification and changing the molar ratio of metal active components, the additive is combined with surface aluminum atoms, the framework strength is enhanced, pore channel collapse caused by acid / water erosion is reduced, the water resistance and acid resistance of the catalyst are improved, and the catalytic reaction activity is further improved. The catalyst disclosed by the invention is accurate and controllable in structure, can be synthesized in batches, and can be applied to the co-catalytic hydrogenation process of biomass pyrolytic oil and / or a model compound thereof and petroleum distillate oil and / or VR.

Provided are: a crystalline sulfide solid electrolyte, which has an improved ionic conductivity while adopting a liquid phase method, contains predetermined atoms, has a diffraction peak in X-ray diffractometry using a predetermined CuKα ray, and has a thio-LISICON Region II-type crystal structure as a basic structure; and a method for producing a crystalline sulfide solid electrolyte, the method including mixing using predetermined complexing agents and an instant drying step.

The invention discloses a sulfur disproportionation-mediated low-temperature high-efficiency low-carbon denitrification and synchronous ammonium recovery method for sewage, belongs to the field of sewage treatment, and aims to solve the problems that an existing autotroph denitrification process cannot adapt to water quality fluctuation and seasonal variation and is poor in engineering applicability. Polyculture denitrification and elemental sulfur disproportionation (SD) are used as an effective enhanced denitrification scheme and are applied to a low-temperature SDAD system of actual sewage. Sulfide and polysulfide generated in situ through elemental sulfur disproportionation reaction and low-concentration sodium acetate under the polyculture condition are used as supplementary electron donors, so that the denitrification rate is remarkably increased. The process of reducing dissimilatory nitrate into ammonium (DNRA) in the SD-MixBNR system is beneficial to emission reduction of greenhouse gases while realizing ammonium recovery. According to the method, the SD-MixBNR system can be promoted to be widely applied to actual engineering projects under the carbon neutralization background, and the stability and adaptability of the SD-MixBNR system in the face of various water quality fluctuations and seasonal changes are enhanced.

The invention discloses a preparation method for selectively oxidizing thioether into sulfoxide through photo-initiation, and belongs to the field of synthesis of medical compounds. The preparation method comprises the following steps that in the air atmosphere, a thioether compound is dissolved in an acetonitrile-water mixed solvent, inorganic metal salt catalysts such as ferric chloride and copper sulfate are added, the mixture reacts for 8-48 h at the temperature of 0-45 DEG C under illumination with the wavelength of 295-405 nm, selective oxidation is carried out, and the sulfoxide product is obtained, and the molar ratio of thioether to the catalysts is 5: 1. The method overcomes the problems of excessive oxidation risk, complicated operation, environmental pollution and the like caused by dependence of a noble metal catalyst and use of a strong oxidant in the existing thioether oxidation method, has the advantages of high catalytic efficiency, high yield and excellent selectivity, can greatly reduce the production cost, is suitable for later industrial synthesis and amplification, and has wide application prospects. The method has the advantages of no expensive metal catalyst or oxidant, simple preparation process, high efficiency, environmental protection, safety and cost saving.