Study On Preparation Of SDS/Sepiolite And Its Adsorption Of Rhodamine B

Rhodamine B was a typical basic dyes, which has the molecular structure triphenylmethane was difficult to remove in the environment. Hence, effective degradation of rhodamine B content in printing and dyeing wastewater was extremely important.By comparing this study modified polyvinylpyrrolidone (PVP)/sepiolite with an acid-modified sepiolite and sodium dodecyl sulfate (SDS)/Sepiolite adsorption effect of Rhodamine B, select adsorption the best performance on the study.Experiments show that the modified SDS/sepiolite was the best,corresponding removal rate of rhodamine B was 92%. SDS/sepiolite microstructure was conducted using a specific surface area analysis, scanning electron microscopy and infrared spectroscopy. In the specific surface area analysis, BET surface was 44.8169cm2/g, which was greater than the acid-modified sepiolite(31.4764cm2/g). According to SEM analysis process, SDS/sepiolite pipe changed the original crystal structure into plate-shaped crystals and presented uneven topography. Finally, FT-IR analysis, compared with purified sepiolite without absorption peak in the range of 2839-2927cm-1, SDS/sepiolite have clear contraction vibration peaks of -CH3 and -CH2, indicated that SDS composition load in sepiolite. The experiment showed the optimum conditions of SDS/sepiolite:mass ratio of SDS and sepiolite was 1:10, the reaction solution pH was 2, relatively good SDS/sepiolite can be obtained, meanwhile SDS/sepiolite in experimental studies to determined adsorption of rhodamine B onto SDS/sepiolite in the best conditions that:the dosage of SDS/sepiolite is 0.02g, the concentration of rhodamine B was 35mg/L, pH=3 solution when viewed the best adsorption quantity 24.91mg/g at this time.SDS/sepiolite adsorption kinetics showed that:quasi-second-order kinetic coefficient R2=0.999, thus the adsorption reaction was a chemical reaction. In the study of SDS/Sepiolite adsorption thermodynamics experiment:Langmuir model can fitted different adsorption isotherm and coefficient (R2) were both greater than 0.995, adsorption thermodynamics and found the Gibbs free energy changes between physical adsorption and chemisorption, and thus shows adsorption of rhodamine B onto SDS/sepiolite is mainly chemical adsorption, physical adsorption bonding surface monolayer adsorption. Thermodynamic studies which found that the adsorption reaction ?G<0, so the adsorption process is a spontaneous reaction.Finally, the re-adsorption of Rhodamine B onto SDS/sepiolite was studied. In the experimental re-adsorption:the sum of three times the amount of adsorption (30.39mg/L) was significantly larger than the amount of adsorption(24.91mg/L) in the best conditions, hence, SDS/sepiolite as adsorbent was good recyclability. In the comparison of different conditions of remaking SDS/sepiolite adsorbent to remove Rhodamine B:re-adsorption efficiency of 10% nitric acid system weight is less than the effect of sepiolite adsorption remake modified without conditions, efficient less than 80? adsorption drying remake sepiolite, less than 1% weight sodium hydroxide remake effective amount of adsorption. Experimental results show that:a reasonable condition can improve the effectiveness re-adsorption.