Study On The Preparation Of Modified Zeolite And Its Adsorption Ability Of P-Nitrophenol In Polluted Water

Zeolite is one of the environmental-friendly materials, and its modification can improve zeolite adsorption of organic pollutants in polluted water. This paper studied the different modification conditions on the zeolite absorption capacity of p-nitrophenol. Based on comparison of the adsorption differences of different modified zeolites, the acid modification and heat- modification were also emphasized, regarding the effect of implementation order on the adsorption capacity of zeolite. Through studying the structure of modified zeolites, the related mechanism in adsorption of organic pollutants in water was investigated, with an attempt to a provide a theoretical basis in using modified zeolite to remove organic pollutants in waste water. Simultaneously, at the beginning of this experiment, we used the joint method that integrated acid activation with Heat-activation to activate zeolite, and then organically modified zeolite. The effect of CTMAB dosage, modification time, pH, and other preparation conditions on the adsorption of p-nitrophenol from water with organic zeolite were investigated and the optimal application conditions of organic wastewater containing nitrophenol were also explored in the study. The main results were as followings:(1) Compared with 500℃calcine, 900℃calcine increased the zeolite adsorption capacity even more significantly, but it has destructed the structure of zeolite.(2) Acid modification can remove impurities carried by zeolite and can better the connectivity of pores, thus, adsorption capacity of p-nitrophenol by Acid modification zeolite is better than that of zeolite by simply calcined.(3) Modified zeolite by using organics after pre-activation by the joint methods including acid activation and heat activation, can largely improve the adsorption of p-nitrophenol.(4) Impurities of the zeolite without acid washing may be having an impact on the structure of zeolite during the calcination process. So first modified zeolite with acid and then calcined it less than 500℃is appropriate. (5) When the consistence of CTMAB is lower than in the cation exchange capacity of zeolite, the more contents of CTMAB exist in the bentonites, the stronger adsorptive capacity they have.(6) By modification of the organic zeolite, the pH variation has effects on adsorption capacity. High pH results in increase of p-nitrophenol adsorption.(7) After modification with temperature of 60℃, CTMAB concentration of 1.1%, and modification time of 2 h, organic zeolite has a higher adsorptive capacity for p-nitrophenol.(8) Under the conditions of in dosage of 25 g/L, pH 6, and shaking 50 minutes, its removal rate of p-nitrophenol up to 98.3%.