Tungsten Oxide

With the development of shipping industry, marine and river water pollution caused by ships is becoming more and more serious. Some researchers have proposed a scheme of photocatalytic treatment of ship oil sewage by pre separation + fine filtration + deep oxidation. (1) The oil sewage from the upper part of the tank is pumped into the direction of the upper entrance of the pool in tangential direction, forming a rotating flow, which is divided into a cylindrical type. Under the action of the centrifugal force of water, the oil particles with relatively small relative density converge to the central part of the pool and float up, so that the coarse oil particles are separated out in advance. (2) Through the pre separated oily sewage into the fine filter, the fine filter is in turn from top to bottom, including overflow trough, filter material partition board, biomass filter layer, filter material bearing layer, filter material separator with pore size less than biomass filter material,...

A large number of domestic sewage and industrial waste water are discharged into rivers and lakes, resulting in eutrophication of water bodies, affecting the safety of water and living environment. The algae outbreak will cause the oxygen depletion in the water to lead to the death of the fish. The toxins released by some algae will poison the organisms. We should deal with the algae pollution quickly and effectively. It is an urgent need to control the water pollution. At present, algae removal in water is often done by manual removal, and the treatment efficiency is low. Researchers have developed a new method for purifying algae: magnetic nanomaterials using solid phase, montmorillonite with porous materials as adsorbents, non-toxic and harmless adsorbents, adsorbents for algal porous materials and bismuth tungstate , a photochemical agent used to degrade algae and algae toxins. The method of scheme preparation is as follows: (1) First, the adsorbents are evenly dispersed in water a...

EDTA is a highly effective chelating agent. It has been widely used in chemical analysis, electroplating, medicine, industrial washing products, photographic products and other industries. Unfortunately, EDTA can chelate with Mg 2+ , Ca 2+ , Mn2+, Cu 2+ , Fe 2+  and other 50 kinds of metal ions to form water soluble chelates, especially the formation and some toxic metal ions is harmful and difficult from the material, excellent stability, will cause heavy metal diffusion, thus adding heavy environmental pollution. Due to the stability of chelating agents, the degradation of EDTA is more difficult than traditional treatment methods, so bismuth tungstate photocatalyst has become a hot choice again. The fact that bismuth tungstate is can play a big role, especially in the petal like Bi 2 WO 6 , visible light catalytic activity is high, can split water to produce oxygen and organic matter degradation, is a kind of photocatalytic agent ideal for environmental pollution control.  ...

Bismuth tungstate (Bi 2 WO 6 ) is the most common Aurivillius type oxide and is a hot spot in the field of photocatalysis. Most of the traditional photocatalytic reactions are carried out in the suspensions of bismuth tungstate catalyst powders. Although they have high photocatalytic activity, bismuth tungstate powders are easy to agglomerate and difficult to separate and recover. In practice, it was recognized that some measures had enabled bismuth tungstate to work, and some scholars had thought of loading bismuth tungstate onto the cloth. Of course, loading bismuth tungstate on cloth is not a simple mix, and it also requires a series of chemical procedures that combine bismuth tungstate with cloth to function. Acrylic, polyester fiber and so on, have the same effect at last, and their main difference is synthetic method. Some scholars used polyester as the carrier of bismuth tungstate and prepared them by hydrothermal method, the polyester fabric was treated with acetone and eth...

Bismuth tungstate is a popular new visible light catalyst, especially petal shaped bismuth tungstate. It has good light absorption and high stability, and has broad application prospects in the field of photocatalysis. The scholars in our country believe that the proper doping of bismuth tungstate, the preparation of semiconductor compound and assistant modification are effective ways to improve the photocatalytic property of bismuth tungstate. In recent years, graphene has brought tremendous changes to the material industry because of its unique two-dimensional structure, large specific surface area and high electron transmission rate. It has been recognized as the "king of new materials", Chinese scholars believe that graphene as an efficient electronic additive, and Bi 2 WO 6  composite catalyst, will greatly improve its light capture electronic capabilities, thereby enhancing catalytic capacity. However, scholars believe that only graphene is not enough, and the number o...

  In recent years, because bismuth tungstate (Bi 2 WO 6 ) has narrower band gap and wider visible range than titanium dioxide (TiO 2 ), it has a great tendency to replace TiO 2 . However, in practical applications, it was found that bismuth tungate is good, but there are some shortcomings, mainly in its photogenerated electrons and holes easy to complex, quantum efficiency is not high. Therefore, scholars believe that bismuth tungstate should be added with some elements to excite the photocatalytic potential of bismuth tungstate. Some scholars have made Au (Ag) / Bi 2 WO 6  nanocomposites with bismuth tungstate doped with gold or silver. The results show that the degradation efficiency of RhB solution is 40% using Au (Ag) / Bi 2 WO 6  nano photocatalyst, and the efficiency is 99.2%, higher than that of pure Bi 2 WO 6 . Some scholars have suggested that the Pt/Bi 2 WO 6  composite can be used for photocatalytic degradation of Mo methyl orange by doping bismuth with p...

Benzoic acid is a flake or needle like crystalline with a smell of benzene or formaldehyde, usually made by selective oxidation of toluene. Toluene is obtained by a series of oxidation processes. Benzoic acid is an important food preservative, and is also used in medicine, dye carriers, plasticizers, spices and antibacterial agents. In the traditional chemical process, the production of benzoic acid from toluene requires selective oxidation of toluene under severe conditions, such as high temperature, high pressure, and acidic solvents. Generally speaking, the process is costly and polluting. Tungstate is a kind of photocatalyst which is widely used in industrial wastewater treatment, but some scholars have made use of the principle of petal type bismuth tungstate photocatalyst to produce benzoic acid. Because bismuth tungstate can use oxygen as oxidant to catalyze the oxidation of toluene and its derivatives, thereby simplifying the preparation of benzoic acid and reduc...

Bismuth tungstate is a new type of photocatalyst which has attracted much attention in recent years. It has not only good catalytic performance, stable photocatalytic activity, but also non-toxic environment. It is becoming a new hot spot in the field of photocatalyst. The liquid phase methods for preparing bismuth tungstate include solvothermal method, precipitation method, microemulsion method, hydrothermal method, etc.. Among the many methods, hydrothermal method has become the most popular method because of its simple operation process, high utilization ratio of raw materials, less energy consumption, and conforms to the policy of energy saving and emission reduction. The working principle of the hydrothermal method is in a closed reaction vessel special (autoclave), using aqueous solution as reaction medium, heating the reaction vessel, creating a high temperature and high pressure reaction environment, the insoluble substances dissolved in normal temperature and ...

Bismuth tungstate is a new photocatalyst developed in recent years. It has the characteristics of narrow band gap, good catalytic performance, stable photocatalytic and environmental protection, and has become a new hot spot in the field of photocatalyst. The preparation methods of bismuth tungstate mainly include solid phase method and liquid phase method. In general, they are fire process and wet process. Solid phase method is the preparation of bismuth tungstate by sintering at high temperature, compared with the liquid phase method, the solid phase method is more adopted by enterprises. Because most of the smelting enterprises adopt solid phase method to obtain tungsten powder, calcination equipment can be used in conjunction with each other, and the equipment foundation is the reason why solid phase method is more popular. The synthesis principle of bismuth tungstate solid phase method is mechanical processing containing Bi and W elements in the oxide material or its...

Dye pollution is one of the most important environmental pollution sources in the world. Dye wastewater has the characteristics of complex composition, high chromaticity, large amount of emission, toxicity and biochemical degradation. It has been a difficult problem in wastewater treatment. In recent years, with the development of photocatalytic technology, more and more photocatalysts have been developed. Bismuth tungstate has been widely used for its excellent photocatalytic degradation ability, there is no doubt that bismuth tungstate has better degradation effect on dye wastewater. However, in recent years, it has been found that bismuth tungstate is good, but it is easy to assemble, difficult to separate and difficult to recover. In order to solve this problem, some scholars have proposed a scheme for making composite materials of bismuth tungstate and acrylic fiber. Acrylic fiber is also called polyacrylonitrile fiber, also known as synthetic wool, and bismuth tungst...

China is a major producer of antibiotics and one of the most serious countries that abuse antibiotics. Livestock farming is the hardest hit by the use of antibiotics, with the rapid development of aquaculture, the residues of antibiotics in water, sediment and soil become more and more serious. Tetracycline is the most common antibiotic used in livestock farming. Its main characteristics are broad-spectrum antibacterial and cheap, unlike other organic wastewater contamination, tetracycline and other antibiotic compounds usually have a shorter degradation half-life in the environment, however, the use of tetracyclines in livestock and aquaculture has never ceased to allow them to enter the environment, manifested as "persistent". Such a consequence is that antibiotics selectively inhibit some environmental microorganisms in the environment and induce the emergence of some antibiotic resistance groups, thus triggering a particular ecotoxicological effect, this is why s...

Bismuth tungstate (Bi 2 WO 6 ) is an oxide with perovskite like structure, and is a typical n type semiconductor. Bismuth tungstate has become a new hot spot of photocatalysis because of its unique crystal structure. The preparation methods of bismuth tungstate include solvothermal method, precipitation method, microemulsion method, hydrothermal method, etc.. Among them, microemulsion method is a new method for preparing ultrafine powders, which can be used to prepare nanometer bismuth tungstate, which is relatively simple and the powder morphology is easy to control. Microemulsion refers to two mutually insoluble reaction solutions which form isotropic and thermodynamically stable emulsions under the influence of surfactants, the reactants are nucleated, agglomerated, agglomerated, crystallized and grown in tiny vacuoles and then treated at high temperatures (usually less than 240 degrees) to form nanoparticles. Microemulsion can be divided into three types: water-in-oil...

Bismuth tungstate (Bi 2 WO 6 ) is an oxide with perovskite like structure, and is a typical n-type semiconductor. Because of its unique crystal structure, Bi 2 WO 6  has the properties of thermoelectric, ferroelectric, piezoelectric, oxygen ion conductor, luminescence, nonlinear dielectric induction and catalysis. The preparation methods of bismuth tungstate include solvothermal method, precipitation method, microemulsion method, hydrothermal method, etc.. Among the many methods of liquid phase preparation, hydrothermal process has high utilization ratio of material and less energy consumption because of its simple operation process. But there is a clear flaw in hydrothermal methods, that is, the water sensitive compounds are not satisfactory, so people will use organic solvents instead of "water" in hydrothermal method, which is called solvothermal method. The principle of solvothermal method is similar to thydrothermal method. It also works in a special sea...

In recent years, photocatalytic degradation technology has been paid more and more attention to the treatment of environmental pollution. Photocatalytic treatment of pesticide wastewater is considered to be an ideal method from energy consumption and effect. The tungstate photocatalyst is well received by people for its energy saving, high efficiency, easy operation, wide application range, thorough degradation of pollutants and no secondary pollution. Bismuth tungstate is also a kind of tungstate. Since 1999, it has been reported that bismuth tungstate Bi 2 WO 6  has photocatalytic activity after visible light radiation at wavelengths greater than 420 nm. Bi 2 WO 6  can be excited by visible light and has a high catalytic activity under visible light due to its narrow bandgap width (about 2.7eV) and become a new addition to photocatalytic materials. Some scholars have found in the visible light response Bi 2 WO 6  can effectively degrade harmful substan...