Study On The Adsorption Mechanisms And Application Of ?-Cyclodextrin Polymer To Heavy Metals And Organic Pollutants

As the fast development of modern industrialization,heavy metals ions and organic pollutants had become the most common pollutants in water environment.Although most of these compounds existed as low concerned,many of them have considerable toxicological problems.At present,the majority of the traditional water purification technology couldn't effectively remove heavy metals and organic pollutants.Therefore,it was necessary to find a kind of environmental,economic and effective purification method for the advanced treatment of drinking water.Adsorption as a kind of operating convenience,low-cost wastewater treatment method was ineffect to treat drinking water caused by heavy metals and organic pollutants at low concentration level.On this premise,it was of great significance to research an efficient,low-cost and green adsorbent used in advanced treatment of drinking water.This study was aimed at purity the heavy metals and organic pollutants of drinking water by the use of beta cyclodextrin polymer??-CDP?.To reseach the adsorption mechanisms,related factors and regeneration methods,so as to providing reference for specific applications for?-CDP.The main research contents were as follows:?1?Under the alkaline condition,the?-CD monomer were polymerized to synthesize?-CDP by using the epichlorohydrin as crosslinking agent.The structure and physical-chemical properties of the materials were characterized by SEM,FT-IR,XRD.By comparing with the adsorption effect of?-CD,it was found that?-CDP had better adsorption effect than?-CD.?2?The effects of adsorption time,dosage and pH value were studied by taking Cu²⁺as the representative of heavy metal pollutants and chlorobenzene as the representative of organic pollutants.The influence of the three factors on the adsorption of two pollutants was consistent:The adsorption capacity was positively correlated with the time,and then the adsorption rate slowed down until the adsorption capacity reached the maximum value;With the increase of dosage,the equilibrium adsorption capacity decreased,but the removal rate increased.The optimal dosage was 0.2 g;The best removal effect was in the neutral condition of pH=7.0;?3?From perspectives of adsorption kinetics and adsorption thermodynamics to study adsorption mechanisms of?-CDP on Cu²⁺and chlorobenzene.The adsorption process of the Cu²⁺and chlorobenzene were more accordant with the two order kinetic model,which indicated that the?-CDP had multiple adsorption sites and the adsorption reaction was dominated by chemical adsorption.The obtained data were fitted by Langmuir and Freundlich adsorption isotherm.The results showed adsorption process was more accorded with the Langmuir adsorption isotherm,which meaned that?-CDP was mainly adsorbed on monolayer adsorption and the adsorption sites uniformly distributed.?4?The adsorption experiments of?-CDP on quartz sand were carried out.Orthogonal experiments were carried out to investigate the effects of different factors,such as filling height,filtration velocity and particle size.Among them,the influence of filling height was the most significant.The breakthrough curves of different filling height and different initial concentration of pollutants were researched.The result was adsorption of the two penetration point?TA?and exhaustion point?TB?relationship with the initial concentration of pollutants and filling height;The relationships between the adsorption breakthrough point?ta?and the exhaustion point?tb?with the filling height and the initial concentration of pollutants were obtained.The Yoon-Nelson model was used to fit the data and the related parameters were obtained.?5?The regeneration methods of?-CDP were investigated,and the different mechanisms of acid regeneration and ethanol regeneration were analyzed.The adsorption capacity of?-CDP was only slightly reduced after repeated regeneration,which indicated that the polymer had high chemical stability and regeneration ability.