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Wastewater containing chromium hazards, a wide source of chromium ore processing, electroplating, tanning, dyeing and printing has a large number of the chromium-containing wastewater. The conventional treatment methods exist chemical precipitation sludge reprocessing high-cost, easy to cause secondary pollution. Preparation of chromium with chromium-containing wastewater by modified bentonite, for handling waste containing national priority pollutants? The volatile phenol wastewater, not only is expected to resolve the phenolic wastewater governance issues, but also to solve the chromium wastewater treatment sludge problem, reach The purpose of the treat waste. The papers with chromium-containing wastewater Preparation of chromium modified soil hydroquinone, aminophenol, chlorophenol and actual phenolic wastewater as the research object, research the chromium modified bentonite their appropriate conditions in the adsorption process. amount of stability and regeneration conditions. According to the results of the adsorption experiments with commonly used adsorbent economic and technical comparison, and chromium modified bentonite adsorption phenolic mechanism and thermodynamics, kinetics of the process are discussed. The results show that of Cr 3 the modified bentonite chromium content increased significantly, the expansion of the layer spacing, strong acids and bases and the adsorption of different concentrations of hydroquinone conditions, basic chromium ions does not elute. 25 ℃, pH value of 8 conditions, draw the curve of a hydroquinone equilibrium concentration of the countries industrial wastewater pollutants emission standards, the amount of modified soil and the cast sample volume equation: y = 0.126x -0.1971, R 2 = 0.9473. Plotted the adsorption isotherm, experimental saturated adsorption amount of 88mg / g, with the calculated value is basically the same. The chromium modified bentonite by heating, acid, alkali regeneration. The effect of alkali regeneration acid regeneration. The chromium modified sorb aminophenol, the orthogonal experiments show that the larger factors in turn affect the remaining concentration of the initial concentration, time, acidity, temperature chlorophenol. Thus determine aminophenol appropriate adsorption conditions: time of 150min, pH = 10, temperature 30 ° C; suitability of Chlorophenol adsorption conditions: time 60min, pH = 10, the temperature of 20 ° C. Chromium modified bentonite, COD removal of up to 80% of the actual phenolic wastewater treatment effect. Chromium modified bentonite hydroquinone, p-aminophenol, chlorophenol adsorption law in line with the hydrogen bonding mechanism. Thermodynamic Studies on the adsorption of hydroquinone, adsorption heat of adsorption ΔH = -19.91kJ/mol, belongs to hydrogen bonding heat range. Kinetic studies showed that the initial adsorption stage is controlled by the diffusion process, the entire stage is more in line with the monolayer adsorption law. Simple economic comparison shows that chromium modified single soil only $ 7 per kilogram phenol, far lower than the cost of activated carbon and organic bentonite. Therefore, the preparation of wastewater containing chromium chromium modified bentonite for phenolic wastewater treatment has some practical value.
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