71results about How to "Improve photodegradation efficiency" patented technology

The invention relates to a preparation method of TiO2 photocatalyst by loading TiO2 to diatomite formed in advance and doping rare earth, and belongs to the technical field of photocatalysis. The preparation method comprises the steps of: pickling original diatomite, roasting the pickled diatomite, and uniformly mixing the roasted diatomite, a binder, a fluxing agent and the like so as to obtain molded diatomite; and using tetrabutyl orthotitanate and dehydrated alcohol as raw materials, preparing TiO2 and rare earth doped TiO2 sol by a sol-gel method, macerating the preformed diatomite in the sol, drying the macerated diatomite, and calcining the dried diatomite so as to obtain the load type photocatalyst. The photocatalyst can prevent the TiO2 from running off; besides, the rare earth is doped, so that the utilization rate of visible light by the TiO2 is increased; when a mercury-vapor lamp is used for 3 hours, 95% of a rhodamine b solution can be degraded; when the photocatalyst is illuminated for an hour under sunlight, escherichia coli can be thoroughly killed; when the photocatalyst is illuminated for 24 hours by common daylight lamps, 92% of methanal can be degraded; the photocatalyst is excellent in photocatalytic property and stability, which indicates that the photocatalyst has favorable application prospects in the respects of waste water treatment, sanitation and sterilization, air purification and the like.

The invention discloses a preparation method of metastable phase bismuth oxide and application thereof in photocatalytic degradation of organic pollutants. The preparation method comprises the following steps: carrying out hydrothermal reaction on an aqueous solution which contains ammonium bismuth citrate, urea and hexadecyl trimethyl ammonium bromide to obtain bismuthyl carbonate microflowers; and calcining the bismuthyl carbonate microflowers in an air environment to obtain the metastable phase bismuth oxide beta-Bi2O3/Bi2O2.33@Bi2O2CO3. The preparation method is simple and controllable to operate, and is environmentally friendly. The synthesized metastable phase bismuth oxide has the advantages of visible-light response, large specific surface area, high catalytic activity and the like, has the characteristics of rapidness and high efficiency in a process of visible-light catalytic degradation of the organic pollutants, and can be widely applied to the technical field of treatment of the organic pollutants.

The invention discloses a preparation method of a CdSe/BiOCl composite photocatalyst, belonging to the technical field of environmental material preparation. The method comprises the following concrete steps: dissolving cadmium chloride and methacrylic acid by using deionized water, stirring, then adjusting a pH value, injecting supernate formed after selenium powder and sodium borohydride are dissolved in deionized water, introducing nitrogen gas, heating, then cooling naturally, centrifugalizing, washing, and drying to obtain CdSe quantum dots; dissolving bismuth nitrate pentahydrate into amannitol solution, dropwise adding a saturated sodium chloride solution, stirring, then pouring the mixture into a reaction kettle, performing hydrothermal reaction, then cooling naturally, centrifugalizing, washing, drying and stoving to obtain BiOCl nanosheets; weighing the prepared CdSe quantum dots and BiOCl nanosheets, mixing and stirring the CdSe quantum dots and the BiOCl nanosheets in a water solution, then centrifugalizing, washing, drying and stoving to obtain the CdSe/BiOCl composite photocatalyst. The photocatalyst has a relatively good shape and stability, and visible light can beeffectively utilized to degrade tetracycline in antibiotic wastewater.

The invention discloses a method for preparing a niobate photocatalyst, and relates to a method for preparing a photocatalyst. The method solves the problems that a photocatalyst prepared by the prior method has poor adsorptivity and low photodegradation efficiency. The preparation method comprises the following steps: 1. niobium pentaoxide and potassium hydroxide are weighed, and a mixture is prepared through magnetic stirring; 2. the mixture is placed into a high-pressure reaction kettle to be prepared into a precursor of the niobate photocatalyst; and 3. the precursor of the niobate photocatalyst is filtered, washed and dried. The invention is to adopt a method of synthesis by a hydro-thermal method to realize the synthesis of the niobate photocatalyst first. The obtained product has high purity, good absorption performance, and high photodegradation efficiency; and the method has cheap raw materials, simple process and simple equipment.

The invention discloses a rare earth element-doped bismuth oxide photocatalyst and a preparation method thereof and belongs to the technical field of photocatalysts for treating organic pollutants. The rare earth element-doped bismuth oxide photocatalyst has active components of bismuth oxide and one or more rare earth elements, wherein the one or more rare earth elements comprise europium or/and cerium. The preparation method comprises the following steps of adding ethylenediaminetetraacetic acid and ammonia water into distilled water, stirring with heating until full dissolution, adding bismuth oxide, ionic liquids and europium oxide or/cerous nitrate into the mixed solution, heating in a water bath kettle to obtain xerogel and carrying out sintering and grinding to obtain rare earth element-doped bismuth oxide photocatalyst particles. Through doping of different metal ions and ionic liquids having different concentrations, a high adsorption capacity and a high light absorption capacity of the rare earth element-doped bismuth oxide photocatalyst are improved and the rare earth element-doped bismuth oxide photocatalyst is a novel photocatalyst having good light absorptivity and a strong degrading capability in the visible region. The preparation method is simple, allows mild conditions and does not produce secondary pollution in preparation.

The invention discloses a preparation method of a titanium dioxide/graphene composite material. The preparation method comprises the following steps: heating a mixture of graphite and peroxide, adding water, applying ultrasonic, mixing with a reducer water solution and a titanium salt precursor water solution, and carrying out hydrothermal reaction, wherein the reducer is hydrazine hydrate, p-phenylene diacrylate, glucose or ascorbic acid. The preparation method disclosed by the invention can adopt one-step reaction, and is simple to operate; and the prepared composite material has high photocatalytic efficiency.

The invention discloses a nano flower-shaped ZnO photocatalyst, a preparation method and application thereof. The nano-flower-shaped ZnO photocatalyst is of a three-dimensional nano-flower structure formed by stacking nano-sheets in a staggered mode, wherein the appearance is uniform, the crystallization performance is good and sufficient high-activity crystal faces are exposed on the surface, sothat in a reaction process with the photocatalyst, aggregation of single nano-particles can be prevented, and the photodegradation efficiency of pollutants is further improved. The method is simple tooperate in the preparation process and low in cost, and has good reusability and stability. The ZnO photocatalyst can degrade organic pollutants under different illumination conditions, and has gooddegradation capability.

The present invention relates to the preparation process of light degradable nanometer composite plastic. The preparation process includes the modification of nanometer TiO2 powder with surface modifier to obtain nanometer modified TiO2 powder; dissolving polystyrene, foamed polystyrene or polyvinyl chloride in chloroform or tetrahydrofuran as solvent; adding nanometer modified TiO2 powder; and volatilizing solvent to prepare the light degradable nanometer composite plastic, which has the weight ratio between polystyrene, foamed polystyrene or polyvinyl chloride and TiO2 powder in 100 to 0.5-5. The present invention has low cost and simple technological process, and the prepared light degradable nanometer composite plastic may be degraded in the sun to reduce white pollution.

The invention discloses an automatic sewage treatment system based on a constructed wetland. The system comprises wetland plants, a drawer type sealed wetland box where various filtering matrixes are laid therein, a water inlet pipe, a water seepage pipe, a water storage cavity, a water outlet pipe, a controller, a detector and an electronic display screen. The water inlet pipe and the water seepage pipe are sequentially communicated with the water storage cavity, the wetland box and the water outlet pipe. The water storage cavity is communicated with the wetland box. Flow guide holes are formed in a flow guide plate. The electronic display screen is installed on the ground, and the controller and the detector are arranged in the electronic display screen and connected with the wetland box through signals. According to the automatic sewage treatment system based on the constructed wetland and a control method of the system, control and detection units and the like are adopted, and intelligence of the sewage treatment system is enhanced. Meanwhile, the nitrogen and phosphorus removal efficiency of the constructed wetland sewage treatment technology is improved, the problem that a traditional constructed wetland treatment technology cannot eliminate heavy metal pollution easily is solved, and workloads for later maintenance of the sewage treatment system are reduced.

The invention discloses a zinc oxide/carbon quantum dot composite photocatalyst, a preparation method and application thereof. Aiming at the problems existing in the zinc oxide composite photocatalystat present, the synthesis method of the zinc oxide composite photocatalyst is improved; the zinc oxide/carbon quantum dot composite photocatalyst is prepared by combining carbon quantum dots with three-dimensional zinc oxide nanoflowers synthesized by a hydrothermal method. The structure of the composite photocatalyst is a nanoflower formed by stacking nanosheets, the synthetic morphology is uniform, and the composite photocatalyst has good crystallization performance. The composite photocatalyst can be used for treating various organic pollutants under simulated sunlight, and the problems oflow photocatalytic efficiency, poor reusability, high production cost and the like of the traditional photocatalyst in the prior art are solved. Meanwhile, the preparation method is simple to operateand low in cost, and has good reusability and stability.

The invention relates to a preparation method of a visible light response type TiO2 (titanium dioxide) precursor and a prepared TiO2 precursor and a catalyst thereof. The preparation method comprises the following steps of (1) adding titanate and organic macromolecules into a reaction container, adding boric acid at the temperature of 50 to 90 DEG C, and reacting at the temperature of 100 to 120 DEG C until a solution is clear and transparent; (2) at the temperature from room temperature to 90 DEG C, adding a nitrogen-containing compound, heating and refluxing; (3) at the temperature from room temperature to 100 DEG C, adding a chelating agent, heating and refluxing; and (4) at the temperature from room temperature to 80 DEG C, dripping a mixed solution of water and alcohol, refluxing after dripping, cooling, relieving pressure, and removing a solvent, so as to obtain the TiO2 precursor. The preparation method has the advantages that the TiO2 precursor can be dissolved into a common solvent, so that the TiO2 precursor can be loaded on substrates of fibers, molecular sieves and the like by simple impregnating; the substrate for loading the precursor is sintered at high temperature in air, and the precursor is converted into a TiO2 photocatalyst to be loaded onto the substrate, so that the problem of recycling of the catalyst is solved, and the problem of no response of common TiO2 catalyst to the visible light is also solved.

The invention relates to a light degradable TiO2- polystyrene composite plastic preparation method which consists of, carrying out nano TiO2 surface modifying, charging 0.5-5 wt% of modified nanometer TiO2 into styrene monomer, employing home position polymerization method to produce the light degradable TiO2- polystyrene composite plastic.

The invention discloses a sewage treatment system convenient to maintain based on constructed wetlands. The sewage treatment system comprises wetland plants and is characterized by further comprising a drawer type sealed wetland box in which multiple filtering substrates are laid; the wetland plants are planted on the wetland box, a plurality of drawer layers with containing cavities are arranged in the wetland box, and the filtering substrates for purifying sewage are placed in the drawer layers respectively; large bluestone blocks, small gravels, fine sand, modified zeolite, nano composites and a soil layer are placed on the drawer layers respectively from bottom to top. According to the sewage treatment system convenient to maintain based on the constructed wetlands, the nitrogen and phosphorus removal efficiency of the constructed wetland sewage treatment process is enhanced, the problem that heavy metal pollution is hard to remove through a traditional constructed wetland treatment process is solved, and meanwhile the workload of later maintenance of the sewage treatment system is reduced.

The invention discloses a preparation method of graphite-like carbon nitride/graphene/graphene oxide composite aerogel. The preparation method specifically comprises the following steps: step 1, grinding urea or melamine or a mixture formed by mixing urea and melamine in any ratio into powder, and heating to prepare graphite-like carbon nitride; step 2, mixing the graphite-like phase carbon nitride obtained in the step 1 with distilled water; step 3, uniformly mixing the graphite-like phase carbon nitride nanosheet aqueous dispersion liquid with a graphene oxide aqueous solution and a vitamin C aqueous solution; step 4, performing high-speed centrifugation on the precursor sol; and step 5, drying the wet gel by using a freeze dryer to obtain the graphite-like carbon nitride/graphene/graphene oxide composite aerogel. The invention also provides the graphite-like carbon nitride/graphene/graphene oxide composite aerogel prepared by the method. Compared with graphite-like carbon nitride, the graphite-like carbon nitride/graphene/graphene oxide composite aerogel has the advantage that the degradation efficiency and degradation rate of organic dye degraded by a photocatalytic material are improved.

Disclosed is a preparation method of glass fiber-based yttrium doped titanium dioxide photodegradation catalytic filaments, which is characterized in that the method comprises the following steps: (1) preparing an yttrium doped titanyl tartrate solution; (2) washing fiber glass filaments clean with water; (3) heating the clean fiber glass filaments to a temperature of between 50 and 80DEG C, soaking the filaments to the yttrium doped titanyl tartrate solution with the temperature of between 50 and 80DEG C, and adopting a soakage Czochralski method to form an yttrium doped titanyl tartrate precursor film on the surface of the fiber glass filaments; and (4) implementing the heat treatment to the fiber glass filaments coated with the yttrium doped titanyl tartrate precursor, when in heat treatment, the room temperature is taken as an initial temperature which is elevated to between 480 and 520DEG C at a heating rate of 10 to 20DEG C/min, and the heat is preserved for 30 to 60 minutes, and finally the finished product is acquired after natural cooling.

The invention discloses a novel method for preparing a rubidium sulfate (Rb2SO4) modified titanium-based TiO2 film photocatalyst and application thereof to the aspect of photocatalytic degradation of organic pollutants. The preparation method comprises a step 1) of titanium sheet polishing, a step 2) of hydrothermal preparation, a step 3) of natural cooling and airing and a step 4) of calcination for finally obtaining the rubidium sulfate modified titanium-based TiO2 film photocatalyst. Moreover, through calcination of titanium-based TiO2 titanium sheets at different preparation time, the photodegradation capability of organic dyes under different morphologies is explored. Through in-situ growth of the TiO2 sheets and the doping of different elements for modification of the surface structure of the TiO2 sheets, the photocatalyst which is efficient and low in cost is prepared; and the photocatalyst is applied to the process of degrading printing and dyeing wastewater. TiO2 is modified in a metal and non-metal co-doping mode, and the mass transfer of pollutants to the photocatalyst can be quickened, so as to improve photocatalytic degradation efficiency of the photocatalyst.

The invention discloses a method for preparing a carbon-doped bismuth oxychloride nanoflower powder. The method specifically comprises the steps of adding bismuth nitrate pentahydrate and nickel chloride to glycerol for dissolution separately , and then uniformly mixing the two solutions; placing the mixed solution in an oven for hydrothermal reaction to obtain a solid-liquid mixture; and washingthe solid-liquid mixture and conducting drying to obtain the carbon-doped bismuth oxychloride nanoflower powder. According to the invention, the carbon-doped bismuth oxychloride nanoflower powder is prepared by conducting a one-step hydrothermal process on a common chemical raw material bismuth nitrate pentahydrate and nickel chloride. The obtained bismuth oxychloride powder have a flower-like structure formed by gathering of a nano-scale layer structure, so that the specific surface area and the reactive active site of the material are increased, the photodegradation efficiency of the material is significantly improved, meanwhile carbon element introduced by the doped solvent glycerol changes the energy band structure and the forbidden band width of the material, and extends the spectralresponse range of the material to a visible light region, and thus the application limitation of a single bismuth oxychloride material is broken.

The invention discloses an efficiently-degradable oil sand tailing flocculating agent. The efficiently-degradable oil sand tailing flocculating agent is obtained by adopting a nanometer titanium dioxide inorganic composite particle as a nucleus and polyacrylamide as a film, wherein the nanometer titanium dioxide inorganic composite particle is obtained through coating kaolin with titanium dioxide,and the polyacrylamide is bonded on the surface of the nanometer titanium dioxide inorganic composite particle. The efficiently-degradable oil sand tailing flocculating agent can effectively improvethe photodegradation efficiency of the polyacrylamide, and also can solve the problem of uneven dispersion of the nanometer titanium dioxide. The invention also provides a preparation method of the efficiently-degradable oil sand tailing flocculating agent. The preparation method has the advantages of simple steps, easiness in operation, mild and easily-controlled preparation conditions and high efficiency. The flocculating agent can be used in the field of polymer flocculation degradation to substitute traditional polyacrylamide, and solves the problem of pollution of outward discharge of oilsand exploitation tailings to the environment. The preparation method has the characteristics of no influences on the action effect of the flocculating agent, environmental protection and low cost.

The invention relates to a device and method to degrade polycyclic aromatic hydrocarbon pollutants. The device with modified nano titanium oxide that carries waste shell powder is used to provide efficient and green degradation for polycyclic aromatic hydrocarbon pollutants in wastewater. The device and method have the advantages that waste oyster shells are turned into wealth, efficient photocatalytic degradation is provided for polycyclic aromatic hydrocarbons in wastewater, the environment is protected, and health is maintained for aquatics and human.