Regeneration Of Waste Alumina And Its Adsorption Of Vancomycin

As a common industrial adsorbent,activated alumina is widely used in the fields of antibiotic separation and sewage treatment.In the fermentation production process of vancomycin,activated alumina is mainly used for the decolorization of fermentation broth and the primary separation of vancomycin.Vancomycin has important clinical application value and is regarded as the last line of defense for clinical treatment of antibiotics.Vancomycin has important clinical application value and is regarded as the last line of defense for clinical treatment of antibiotics.However,a large amount of waste alumina adsorbent produced in the vancomycin production process forms solid waste pollution on the one hand,and can not realize the reuse of waste alumina;on the other hand,vancomycin residues in waste alumina will cause new environmental pollution problems.In this study,waste alumina produced during the separation of vancomycin was used as a research object.Through the regeneration of waste alumina,the resource utilization of waste alumina is realized,and the new environmental pollution problem caused by vancomycin residue is solved.The experiment optimizes the regeneration process of waste alumina by means of physical,chemical and other regeneration methods,and studies the characteristics of vancomycin adsorption on alumina after regeneration,and analyzes its adsorption and desorption cycle.The main contents of research are as follows:1.Study on static adsorption test of vancomycin by activated alumina and investigate the effects of the dosage of the active alumina,the concentration of vancomycin and the reaction time on adsorption.The experiment determine the concentration of vancomycin 200 mg·L-1,the amount of activated alumina 1 g and the reaction time 3 hours as the optimal reaction conditions.2.Physical modification optimization for calcination of waste alumina.Simultaneous calcination measured the ash content in the waste alumina,about 12.7%;and the experimental results show that the impurity content of waste alumina is about 12.7%;the sample after calcination at 500? for 3 h has the best adsorption effect,and the adsorption amount is 0.7505 mg·g-1,which is 46.96%higher than waste alumina.3.Chemical modification and orthogonal optimization of the calcined waste alumina are carried out.Determining the conditions of optimization:the citric acid concentration is 0.03%,the solid-liquid ratio is 1:4,the modification time is 2 h;the ferric chloride concentration is 0.15%,the solid-liquid ratio is 1:7,and the soaking time is 6 h.At this time,the amount of vancomycin adsorbed by modified alumina was 1.1142 mg·g-1,and the adsorption rate was 92.85%.4.Characterization of the modified waste alumina by SEM?XRD?BET?FT-IR and other means.Compared with the waste alumina,the surface of the modified alumina composite is relatively smooth and the pore volume and specific surface area are improved greatly,which is near the relevant performance parameters of the activated alumina.The diagram of X-ray diffraction and infrared spectrum showed that the composite modified waste alumina retains the original characteristic peak,indicating that the modification does not destroy and change its basic structure and crystal type.5.The kinetics of adsorption of vancomycin in the waste alumina modified composite solution shows that the temperature rise is within a certain range,which can effectively shorten the time required to reach the adsorption equilibrium.Adsorption of vancomycin by modified waste alumina was modeled by Freundlich Isotherm.It is due to ?G<0,?H>0,?S>0 in the adsorption reaction that the adsorption of vancomycin by modified waste alumina is a spontaneous endothermic reaction with increased entropy.6.Dynamic modified adsorption test of vancomycin decolorizing solution by composite modified waste alumina,the results show that it can effectively recycle about 18 times.In this study,the regeneration process of waste alumina was realized by combining physical and chemical modification.and it will provide theoretical reference for the company to solve the loss and regeneration of activated alumina in antibiotic production.