Study On The Preparation And Performance Of The Emergency Treatment Compound Of Microcystis Aeruginosa

In recent years,the aggravation of organic pollution is likely to cause rapid growth of algae,which deteriorates the water quality of water sources.Excessive algae will affect the traditional water purification process.At the same time,the secondary metabolites(such as microcystins)produced by harmful algae will be released into the water,which seriously affects the safety of water quality.In this paper,chitosan fiber is used as carrier,aloe emodin and MOF are selected as active substances to prepare two new algae inhibitors.The effects of two kinds of algal inhibitors on the growth of Microcystis aeruginosa were investigated,and the inhibition mechanism was further studied.Firstly,the adsorption of aloe emodin onto chitosan fiber was studied.The effects of adsorption time,ambient temperature and initial concentration of aloe-emodin on adsorption were investigated,and adsorption kinetics and adsorption isotherms were fitted.The chitosan fiber loaded with aloe-emodin was characterized by SEM,FT-IR and XRD,and the adsorption mechanism was discussed.The results showed that chitosan fiber could effectively adsorb aloe emodin,the optimal adsorption temperature was 30 ℃,the adsorption equilibrium time was 240 min,the optimal initial concentration of aloe-emodin was 100 mg/L.The actual adsorption capacity under this condition is 19.06 mg/g.The adsorption process accords with the pseudo second order kinetic model and Freundlich isotherm,which belongs to chemical adsorption.There are borntrager’s reaction and Schiff base reaction between chitosan fiber and aloe emodin,rather than simple physical adsorption.Then,the effects of CS-AE fiber on the growth,cell structure,photosynthetic system,antioxidant enzyme activity and toxin of Microcystis aeruginosa were studied.The experimental results showed that when the dosage of cs-ae fiber was 0.6 g / L,the number of algae decreased by 77.6%,the content of chlorophyll a and carotenoid decreased by76.90% and 78.29%,the content of PC,APC and PE decreased by 90.51%,92.60% and87.65%,respectively.The activity of SOD and cat in algal cells was unbalanced during the experiment,which showed a trend of rising first and then decreasing.In addition,CS-AE fiber can effectively reduce the production of algal toxin.Finally,a new type of algal inhibitor(CS-MOF)was prepared by using chitosan fiber to adsorb MOF material.The effect of CS-MOF fiber on the growth of Microcystis aeruginosa was investigated,and its inhibition mechanism was studied.The results showed that when the dosage was 0.6 g/L,the inhibition rate was 85.64%.The content of chlorophyll a and carotenoids in the water decreased by 87.60% and 88.80%,and the contents of phycobiliprotein PC,APC and PE decreased by 99.74%,99.32% and 97.00%,respectively.SOD activity of algae cells in the treatment group was lower than that of normal cells,but CAT activity had no significant change.However,CS-MOF fiber has the adsorption effect on Microcystins,and the total content of microcystins decreased significantly.