| Removal and degradation of water pollutant have focus on study by chemical and environment worker. In this field, adsorption become a hotspot because of environment. cheaper price of materials and easiest purify pollutants. This paper studies that the biomass materials are function of metalions and dye by absorption. This menthod compare to the conventional for some metals and dye with very good adsorption and high efficiency removal performance in purify water pollutants, is more easy to operate in preparation and applications in the process, thus it has paid much attention the good prospects and cheap at present development removal methods in water pollutant.This paper adopts intermittent constant temperature and oscillation experiment instrument. The following work were process:(1)In order to optimize the ultrasonic-assisted extraction of pigment from the husk of buckwheat, a second order quadratic equation for extraction of pigment was adopted with the Box-Behnken model design. And with the extraction absorbance of pigment as response value, effects of ethanol concentration, pH value, and ultrasound time to the husk of buckwheat extraction of pigment productivity were explored based on one factor tests. The results showed that: when the fixed solid-liquid ratio is 1:40, the response surface methodology the optimum extraction conditions were determined for ethanol concentration of 65.25%, pH value of 5.88 and ultrasound time of 28 min. (2)Buckwheat hull has been successfully utilized and potential biosorbent for removal of Cr (Ⅵ) from aqueous solution. Using the static constant temperature oscillation batch method, the studies have been conducted to discuss the effect of different parameters such as the adsorption time, pH of the medium, adsorbent dosage, initial concentration of Cr (Ⅵ). And from the dynamics, thermodynamics further draw adsorption rate constant and adsorption thermodynamics constant△G°,△H°and△S°. And the biosorption mechanism was also investigated by characterize of before and after buckwheat skin on the adsorption. Maximum removal Cr(Ⅵ) (99.85%) was observed at an initial concentration of 100 mg/g, at pH=2, at adsorbent dosage of 0.25 g, at temperature of 25°within 10h of contact time. The Langmuir isotherm adsorption model more reflected the adsorption characteristics and the maximum adsorption 63.61 mg/g. (3)A low cost agricultural waste buckwheat hull after extracted natural pigment was used as bisorobent for removal of a cationic dye methylene blue and Rhodamine-B from aqueous solution. The sorbent was characterized was characterized by FTIR, scanning electron microscopy (SEM). and potentiometric mass titration. The results showed that buckwheat hull is porous material with functional groups such as hydroxyl and carboxyl, and the pHpzc is found to be at pH=4.12. The kinetics of adsorption of methylene blue onto buckwheat hull at several different initial concentrations was determined by batch experiments. The obtained data were analyzed by pseudo-first-order, pseudo-second-order, and intraparticle diffusion equations. Sorption processes were found to follow pseudo-second order kinetics. Intraparticle diffusion was found to take part in sorption processes but it could not be accepted as the primary rate determining step. Langmuir, Freundlich and Dubinin-Radushkevich isothermal equations were applied to fit the adsorption equilibrium data; In addition, the thermodynamic parameters were calculated in the adsorption process. Finally, the removal mechanism was discussed by deduction from pHpzc and FTIR spectra. Response surface methodology based on Box-Behnken design was used to further evaluate the effects of important parameters, namely, pH, initial dye concentration and temperature on the percentage removal of dye. A quadratic model for predicting the optimum point was established. (4)On the above the basis of many work of adsorption, dye analysis and biological adsorption are determinationed of dye absorption single dye component and mixed dye components, studied the dye initial concentration, pH value, buckwheat skin dose and adsorption time to dye decolorization influence.Through buckwheat skin were studied for Cr(Ⅵ) and methylene blue, Rhodamine-B and mixed dye adsorption, combining the characterization of buckwheat skin, discuss the adsorption mechanism with the biomass materials for metal ions and dye molecules in water pollution, which was provided new materials of removing or recycling and agricultural waste depth use for exploring new ways. In order to town-centered materials as adsorbent used to dye wastewater treatment to provide the reference. Further industrial amplification provide design basis for the improvement of agricultural waste, the attached value and promote the further development of water pollution is significance. |
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