| With the development of social economy, the acceleration of the industrialization and modernization of the city, the environmental pollution is becoming more and more serious. Makes the metal ions in a large number of water seriously overweight, which directly endanger the water quality of the source of our water source. Heavy metal pollution refers to the environmental pollution caused by heavy metals or their compounds. Therefore, it is urgent to study and develop a new type of functional materials for the new technology in addition to pollution.This paper use sodium bentonite as raw material, using FeCl2·4H2O and FeCl3·6H2O as modifier. Preparation of magnetic bentonite by chemical co precipitation method (hereinafter referred to as "magnetic bentonite"). In order to evaluate the removal efficiency of Cu2+ and Zn2+in polluted water, a new type of water treatment agent for Cu2+ and Zn2+ was prepared. And the preparation conditions of magnetic bentonite were optimized. The surface morphology and internal structure of bentonite were characterized by comparison and analysis. The effect of the reaction conditions on the removal of Zn2+ and Cu2+ in polluted water was investigated.The experiment results of preparing modified bentonite indicated that the settle properties of modified bentonite is very good at a Cu2+ concentration of 20mg/L and a Zn+ concentration of 25mg/L in polluted water. And the best prepare condition is:n=2, T=80 ℃, t=2h, t=8min, Fe/S=2.Before and after magnetization of bentonite for the X-ray spectroscopy (EDS), hysteresis curve, scanning electron microscope (SEM), infrared ray spectrum (FT IR), X-ray diffraction (XRD) were characterized, and the results showed that bentonite after magnetization, obvious changes in surface characteristics, the magnetic material in magnetic bentonite has combined with layers of bentonite, formed the ferric oxide/bentonite covalent bond; Magnetic layer spacing of bentonite increases by 1.280 nm and 1.654nm.Examines the various reaction conditions on the removal of Cu2+ and Zn2+ in water pollution, the results showed:magnetic bentonite of Cu2+ and Zn2+ has good removal effect; Removal rate as the amount of magnetic bentonite additive increases, when the saturated value, after adding additive, effects on the removal rate of Cu2+ and Zn2+ is not obvious; PH in the range of 7-7.2 Cu2+removal effect is best, pH value in the range of 6.8-7.5 Zn2+ removal effect is best; 30 min before the precipitation, the increase in turbidity removal rate is significant, with the increase of precipitation time, turbidity removal rate tends to balance; With the increase of reaction time, magnetic bentonite on the removal of Cu2+ and Zn2+ increases gradually, after reaching saturation, then gradually decreased; And with the increase of reaction temperature, magnetic bentonite on the removal of Cu2+ and Zn2+ growth not by much.Magnetic bentonite regeneration experiment was carried out by ultrasonic, acid and alkali regeneration looking into the possibility of the recycling magnetic bentonite. Results showed that with the method of the acid regeneration and alkali regeneration regeneration after 5 times, for the removal of Cu2+ and Zn2+ can guarantee over 50%, it is better to remove; Ultrasonic method compared with the former, both regenerative effect is poor. |
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