Catalyst composition for processing methylene blue dye wastewater and preparation method and applications of catalyst composition

Abstract

The invention discloses a catalyst composition for processing methylene blue dye wastewater and a preparation method and applications of the catalyst composition. The method includes adding sodium compounds, chromium salts, molybdate and citric acids into water successively, stirring and dissolving the mixture, adding ethylene glycol, heating the mixture to a temperature of 100 DEG C to 130 DEG C, and stirring the mixture continuously to form gel; and heating the gel at a temperature ranging from 600 DEG C to 1200 DEG C for 5 hours to 48 hours to obtain a ternary composite oxide Na2O*Cr2O3*xMoO3 (x=1-8) catalyst. The catalyst can process methylene blue dye wastewater effectively in no need of oxidants or light illumination. As for methylene blue with a concentration of 110mg / L, the degradation rate of the catalyst can achieve more than 90.0% in 75 minutes, and the catalyst can be recycled for a plurality of times.

Description

technical field [0001] The invention belongs to the technical field of preparation of inorganic functional materials, and relates to a catalyst composition for treating methylene blue dye wastewater, in particular to a ternary composite oxide Na that can degrade methylene blue dye wastewater 2 O Cr 2 o 3 ●xMoO 3 (x=1~8) Catalyst and its preparation method and application. Background technique [0002] At present, organic dye wastewater has become one of the main sources of water pollution. The wastewater has the characteristics of large water volume, high concentration, complex composition, deep color and refractory degradation. Most dyes also have toxic, carcinogenic, teratogenic and mutagenic effects. Methylene blue is an important organic chemical synthetic cationic dye with a wide range of industrial applications. For example, it can be applied to the dyeing of hemp, silk fabrics, paper, bamboo and wood, the dyeing of biological and bacterial tissues, and the manuf...

AI Technical Summary

Problems solved by technology

The biological method is affected by factors such as pH value, temperature, salt and dye type, which makes the effect of biological treatment not ideal

The operating cost of the coagulation method is high, the amount of sludge is large and dehydration is difficult, and the applicable pH range is narrow

The cost of advanced oxidation technology is high, and commonly used oxidants also show shortcomings such as weak oxidation ability and selective oxidation, and impurities are easily introduced during the treatment process to cause secondary pollution

The photocatalytic method requires a light source irradiation system, which is greatly affected by the weather in practical applications

The adsorption method is easily affected by suspended solids and oil in water, and the amount of adsorbent is large and the cost is high

Membrane separation methods are divided into electrodialysis, reverse osmosis, nanofiltration and ultrafiltration, etc. Among them, electrodialysis, reverse osmosis and nanofiltration have the advantages of high dye removal rate and the ability to recover dyes in wastewater. Simple, but the cost of the membrane used is high, and the operating pressure is high, resulting in high energy consumption of the membrane method, which affects its industrial application

Due to the large pore size of the membrane, the traditional ultrafiltration method is difficult to remove low molecular weight organic pollutants