Coating Modification And Preparation Of Activated Carbon And Its Adsorption Properties

Due to the rapid development of China's textile industry,the pressure of printing and dyeing wastewater treatment is increasing day by day.With the rapid development of China's textile industry,the pressure of printing and dyeing wastewater treatment is increasing.If the waste water of dyestuff is discharged without strict treatment,it will cause a very serious environmental pollution problem.The discharge of dyestuff wastewater without strict treatment will cause serious environmental pollution problems.Activated carbon is one of the most commonly used adsorbents.Its large specific surface area and rich functional groups make it often used in various water environment treatments.However,the difficulty in the regeneration of activated carbon and the large amount of material loss and sludge generation after the completion of the adsorption treatment have become the limiting factors for its use.This paper uses two technical methods to improve the recovery and reuse efficiency of activated carbon.The main research contents are as follows:(1)Preparation of activated carbon-sodium alginate composite gel microspheres can be obtained by adjusting the mass ratio of different sodium alginate and activated carbon to obtain gel microspheres xAC-SA with different ratios.Through experiments,it was found that when the mass ratio of activated carbon and sodium alginate is 3:1,the prepared microspheres under the optimal pH 7 and 25?,the adsorbent mass is 10 g/L,and the contact time is 2h.The adsorption capacity of cationic dye methylene blue(MB)reached 16.76 mg/g under adsorption conditions.Adsorption kinetics and adsorption isotherm studies have shown that the adsorption process of gel microsphere adsorbent on MB is more in line with the quasi-second-order kinetic model,and meets the Freundlich adsorption isotherm model.The adsorbent 3AC-SA has good stability and reusability.After 5 times of reuse,the removal rate of MB can still reach 84.72%.By simulating natural water,it was found that the presence of inorganic salt NaCl in dye wastewater had limited influence on the adsorption effect of 3AC-SA adsorbent.When the concentration of the surfactant SDBS is between 0-4 g/L,its presence can obviously promote the adsorption of MB by the adsorbent,and when the concentration of SDBS increases to 6 g/L,it exceeds the surface activity.The critical micelle concentration of the agent itself showed a significant inhibitory effect on the adsorption activity.The presence of humic acid HA will affect the adsorption capacity of 3AC-SA for mixed dyes MB/OR ?.In the absence of HA,the adsorption rates of 3 AC-S A for mixed dyes MB and OR ? reach 92.6%and 85.96%,respectively.However,when HA was introduced,the adsorption rate of MB and OR ? decreased to 57.28%and 84.12%(10 mg/L HA),and the inhibition effect further increased with the increase of humic acid concentration.(2)Using common fruit shell waste as raw material,magnetic activated carbon was prepared in one step.By comparing the yield and adsorption effect of each raw material,the sunflower seed shell was finally selected as the carbon source of the adsorbent,and GMAC was prepared under the conditions of carbonization temperature of 500? and activation temperature of 750? and ferric oxide with magnetic source.Under the optimal pH 7,25?,the adsorbent GMAC mass is 5 g/L,and the contact time is 2h,the maximum adsorption capacity of the adsorbent for methylene blue can reach 54.289 mg/g.The absolute adsorbent was eluted with absolute ethanol.After five adsorption and desorption tests,the removal rate of MB by GMAC decreased from 98.86%to 58.80%.Studies on adsorption kinetics and adsorption isotherms show that the adsorption process of GMAC on dyes conforms to the quasi-second-order kinetic model and the Langmuir isotherm adsorption model,indicating that the adsorption process of the adsorbent GMAC on cationic dye MB is mainly monolayer adsorption.