Metal oxide nanometer material for treating wastewater containing dyes or heavy metal ions, preparation method and application thereof

Abstract

The invention relates to a metal oxide nanometer material for treating wastewater containing dyes or heavy metal ions, a preparation method and application thereof. Compositions of the metal oxide nanometer material is one or a mixture of more than two of CaO, ZrO2, SiO, ZnO, TiO2, MgO, Fe2O3 and NiO. The preparation method comprises the following steps: dissolving one or a mixture of more than two of calcium nitrate containing crystallization water, zirconium nitrate, ethyl orthosilicate, zinc nitrate, butyl titanate, magnesium nitrate, ferric nitrate and nickel nitrate into methanol, ethanol or propanol, adding a phenylcarbinol or benzylcarbinol structure-directing agent into the obtained solution, moving the mixture into a high-pressure kettle after the mixture is mixed evenly, heating the mixture to between 120 and 200 DEG C for 2 to 6h to ensure that nitrate is completely alcoholized under the protection of chlorine gas with the pressure of between 10 and 1.5*10 Pa, then heating the mixture to between 261 and 269 DEG C for 15h, drying the obtained product, and then performing high-temperature roasting at a temperature of between 300 and 500 DEG C to obtain the metal oxide nanometer material. The metal oxide nanometer material is added into the wastewater containing the dyes or the heavy metal ions to ensure that the metal oxide nanometer material and the wastewater are fully contacted to decolorize, absorb or degrade the wastewater containing the dyes.

Description

technical field [0001] The invention relates to a metal oxide nanometer material for treating wastewater containing dyes or heavy metal ions, a preparation method and application. Background technique [0002] In the past ten years, my country's dye industry has achieved tremendous development. At present, my country can produce more than 100,000 tons of dyes in eleven categories each year. Dyes are widely used in textiles, leather, paper, rubber, plastics, cosmetics, pharmaceuticals, and food industries. The extensive use of dyes will inevitably produce a large amount of dye wastewater discharged into environmental waters, resulting in the pollution of natural waters. [0003] Dye wastewater generally has the following characteristics: [0004] (1) Most of the organic matter in wastewater is based on aromatic groups such as benzene, naphthalene, anthracene, and quinone, and has chromophores. The color is very dark, and the chromaticity reaches 500-500,000, which has a str...

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Problems solved by technology

[0006](3) Most of the wastewater is acidic, and some are alkaline, and generally contain a lot of salt

[0007](4) Due to the increasing variety of dyes and the development of anti-photolysis, anti-oxidation, and anti-biochemical degradation, these wastewaters are becoming more and more difficult to deal with in the usual way

[0010](1) The chromaticity of the dye wastewater seriously deteriorates the appearance of the water body, so the main factor causing the chromaticity is the dye

The dyes in wastewater can absorb light, reduce the transparency of water body, affect the growth of aquatic organisms and microorganisms, not conducive to self-purification of water body, and easily cause visual pollution

[0011] (2) Harmful heavy metals such as chromium, lead, and mercury exist in dyes. These heavy metal salts are difficult to degrade by general biochemical methods, so they can exist in the natural environment for a long time. And it will endanger human health through the food chain. In Japan, there have been public hazards such as "water disease" and "pain disease" caused by heavy metal mercury and cadmium pollution.

Although the above-mentioned materials can reach more than 90% in the decolorization efficiency of dyes, some materials have very little adsorption capacity for dyes, such as: the adsorption capacity of alloy materials for dyes is 0.115mg / g, and the montmorillonite containing cyclodextrin has a low adsorption capacity for dyes. The adsorption capacity is 197.2mg / g

Although the treatment effect of bentonite and activated carbon fiber is satisfactory, its cost is high and regeneration is difficult. For example, the activation temperature of activated carbon fiber should be above 800°C and activated with water vapor for 6 hours, which greatly increases the cost and makes the practical application subject to limit

Iron-based complexes have a better decolorization effect on dye wastewater, but the conditions are somewhat harsh. It needs to be adjusted to pH ≤ 2.5 with acid, and the dye molecules must be reduced under the condition of ultraviolet light, which also makes the practical application very difficult. big limit

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