| In this study, the characteristics and applications of bentonite were described. The ways and means to treat oily wastewater were introduced. Especially the preparations, characteristics and applications of organobentonite in environmental protection were also reviewed. Furthermore, the preparations, properties of organobentonite synthesized by using bentonite from Wulanlinge, Xinjiang province have been investigated in detail. The sorption behaviors, mechanisms and rules for organobentonite to adsorb oil from wastewater have been investigated in particular. The reuse and economic analysis of organobentonite used in treating oily wastewater have been investigated as well. It promotes the use and benifits of bentonite and oily wastewater treatment.The preparation of organobentonite using cationic surfactants has been investigated in different conditions. The influences of factors on the sorption of organobentonite have been measured by the removal rate of oil from wastewater made in laboratory. Results indicate that the perfect organobentonite may be obtained under the optimal preparation condition that the addition of sodium rich bentonite is 10%, the addition of cetyltrimethylammonium bromide (CTMAB) and etramethylammoniumbromide (TMAB) is 1% and 5%, reacting for 90min. at the temperature of about 70℃, pH value of 7, aging 12h , and then drying at temperature of about 90℃.The correlation coefficients between the preparation factors and the sorption of organobentonite have been investigated by path coefficients. Study of direct path coefficients shows that the most important factor of them is the sort and dosage of cationic surfactants, and the second is the kind and properties of bentonite. Research of indirect path coefficients indicates that all of the factors not only have direct influence on the sorption of organobentonite, the correlations between the factors but also have indirect influence on it. Surplus path coefficient is 0. 418, which suggests that some other important factors (for exam, the modified methods, the velocity of mixing, measure error margin etc.) should be considered.The structures and properties of organobentonite have been investigated by using mineralogical test techniques. Results of organic content analysis show that the organic content of organobentonite increase as the ration of CTMAB to TMAB increase. Studies on X-ray diffraction date (XRD) demonstrates that it is possible to create large interlayer spacing organobentonite by use of organic cation surfactants with suitable balance between the hydrocarbon and ethylene oxide chain lengths, and the value of dom become larger as the percentage of CTMAB increases in the mixed water with CTMAB and TMAB. Results of infrared spectrum (IR), differential thermal analysis (DTA) and'SEM indicate that cationic exchangereaction only happened in interlayer of bentonites, which may not destroy the basic structure of mentmorillonite but bring a few of changes of organic content in the interlayer spacing.The sorption behaviors for organobentonites to sorb oil from water have been investigated. Results indicate that adsorption abilities of organobentonite are higher than that of bentonite unmodified, and adsorption takes an important role when the ration of long-chain quaternary ammonium (CTMAB) to short-chain quaternary ammonium (TMAB) is less 2, otherwise, partition will be prevail adsorption. Results of mono-factor experiment and orthogonal table prove that the optimum reaction conditions for 1% CTMAB /6% TMAB (Na)bent to treat 50ml wastewater which initial oil concentration is 115. 45mg/l may be obtained with the addition of sorbent about 1. Og, pH of 6, reaction temperature of 35°C, reaction time of about 120min and the mixing rate of about 150r/min. The removal rate of oil can be up to 97. 98% in this condition.The equation of the dosage for 1% CTMAB /6% TMAB bentonite to treat wastewater at different oil initial concentration is obtained by the curves of the relation between oil concentration of balance and dosage of organobentonite at di...
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