Preparation Of Modified Activated Clay And Methyl Orange Dye Wastewater Treatment Research

With the continued increasing of the world's population and rapid development of industry and agriculture, it is not optimistic with the state of global freshwater resources, water scarcity and water quality deterioration, humans will face severe challenges. Now there are water shortages in about80countries that affect their economic development and national life; more than400cities were faced with severe water shortages, severe water shortages, there is a big contradiction between water supply and demand. The main reason is that the water resources division inequality and exploitation of water resources is low, but with the development of the national economy, water consumption is growing rapidly. Our country will be plagued by drought peak in2030, if we do not take effective measure. This makes the recycling of wastewater has become an inevitable trend. A great deal of fresh water was demanded for printing and dyeing industry, and a great lot of industrial effluent was discharged from the dyeing industry in China. In recent years, the importance of national and local printing and dyeing industry wastewater treatment was recognized, which has the character of large volume of water emission, the high content of biodegradable organic pollution, high levels of suspended solids, alkaline, deep color and high COD, it makes that average control rate of about75%of the textile dyeing industry wastewater, the compliance rate was only30%. Therefore, the research cost-effective advanced wastewater treatment technology for dyes has great practical significance. Methyl orange as one of the typical organic pollutants in the printing and dyeing wastewater is the main objective of the printing and dyeing wastewater. In this paper, static batch adsorption, dynamic continuous adsorption and adsorption behavior of aqueous solution of methyl orange as the analog processing object were investigated, in order to find an effective adsorbent adsorption of methyl orange wrastewater.In the first part, first global overview of water resources was introduced. Followed by analysis of the hazards and pollution generated by the dye wastewater, at the same time, bring harm to human existence and the ecological environment and pointed out that the printing and dyeing wastewater discharge. Then, the classification of the dye wastewater treatment methods and further detailed description of the status quo of methyl orange dye wastewater treatment were described; Finally, the use of activated clay(MC), methyl orange(MO) wastewater processing status was presented.In the second part, a low-cost adsorbent modified activated clay (MAC) was prepared by acid modified, and the characterization of the prepared adsorbents was performed using environmental scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), physical adsorption analyzer and other analytical methods. The methyl orange dyeing wastewater was treatment by modified activated clay, the experimental results show that: at pH7, adsorbent dosage of1.0g,100mL of the initial concentration of100mg/L methyl orange dye wastewater, COD removal efficiency reached81.3%at288K after60min, the decolorization rate reached96.3%after180min. Treated wastewater can reach the first grade level of wastewater discharge standards.In the third part, the behavior of activated clay on the adsorption of methyl orange aqueous solution was investigated, which including the factors that affect the adsorption, adsorption isotherms, adsorption kinetics and adsorption thermodynamics. The adsorption equilibrium experiments show that activated clay adsorption of methyl orange is more in line with the Langmuir model, and the adsorption behavior are preferential adsorption; Kinetic studies showed that the adsorption process of methyl orange on activated clay is very suitable for the pseudo second order kinetic model, equilibrium adsorption capacity is reduced with increasing temperature. The adsorption thermodynamic behavior of the whole adsorption process is mainly physical adsorption.In the forth part, methyl orange dyeing wastewater was treated by modified activated clay using the dynamic continuous adsorption. The effect of different breakthrough curves and the penetration point by different flow rates, different column height and wastewater initial concentration was investigated. The experimental results show that:the flow rate of1.78cm/min, column height of3.5cm with the initial concentration of100mg/L methyl orange wastewater, the decolorization rate reached98.9%, and penetration point of the breakthrough curve in464min were obtained.