Experimental Study On Extraction And Purification And Removal Of Microcystins

In recent years,there have been frequent outbreaks of water blooms in Chaohu Lake,and the utilization of fresh blue-green algae in water blooms has received increasing attention.The extraction and purification of useful biomass from Cyanophyta in Chaohu Lake is the main approach for the current recycling of blue algae,especially the extraction and purification of cyanobacterial from cyanobacteria.It is a research hotspot at home and abroad.However,because Chaohu Cyanophyta contains microcystins that cause hepatocarcinogenesis,removal of microcystins needs to be considered in the process of extracting and purifying useful biomass including phycocyanin;The nature and breadth of its toxicology,immunology,and degradation and removal have become the focus of current research,and a large amount of microcystin reagents are needed.Therefore,it is highly practical to extract and purify microcystins through experimental methods.Therefore,this article from the extraction and purification of microcystins and removal of cyanobacterial production of microcystin from the two perspectives of experimental research,reached the conclusions for the study of Cyanobacterial resources in Chaohu provide reference.In this paper,the cyanobacterial disrupted supernatant was used as the research object,and the aqueous two-phase solid-phase extraction method was used as the pretreatment process for MC-RR purification of microcystins,and the optimal operating conditions in each step of the process were explored.Then againThe two-step salting-out supernatant produced during the extraction and purification of phycocyanin was used as the research object.Ultrasonic-coagulation and Fe(III)modified attapulgite clay adsorption were used for the two-step salting out supernatants.The concentration of microcystins was removed experimentally,and the MC-LR and MC-RR removal rates were used as indicators to obtain the optimal operating conditions.The main test results are as follows:In the pretreatment optimization experiment of MC-RR purification in Cyanobacteria,the main parameters of the aqueous two-phase extraction process were analyzed and optimized through orthogonal experiments: after freeze-breaking the blue algae,the first step was performed.Aqueous phase extraction: The pH of the MC-RR crude extract solution was adjusted to 8 and the mixture was extracted 3 times with a mass fraction of 40% n-hexane and extracted for 2 minutes each time.Then,the second step of solid phase extraction was performed: 30 mL of the solution after the first step was passed through the solid phase extraction cartridge at a rate of 0.5 mL/min,and eluted with a concentration of 80% methanol at a rate of 0.5 mL/min.Collect the light yellow eluent that has flowed out for 1 to 3 minutes.After two-step operation,the purity of MC-RR in solution can be increased from 20.96% to 46.71%,and the concentration can be increased from 3.39 mg/mL to 14.63 mg/mL.In the experiment of removing microcystins by coagulation-assisted ultrasonic sorption,the single-factor and orthogonal experiments were used to explore the effect of ultrasonic-coagulation combined with high concentrations of microcystins in supernatants.Theoretical analysis.The results showed that after ultrasonic treatment at a power of 950 W and a time of 10 min,the supernatant pH value was 2,the pH of the solution was adjusted again,and 8 mg/L of aluminum sulfate was added.The coagulation was performed at 100 r/min for 15 min.Better microcystins removal effect can be obtained.The removal rate of MC-RR and MC-LR by coagulation-assisted ultrasound was above 90%.In the comparative experiment of removing microcystin from modified attapulgite clay,the attapulgite clay with 150-178?m particle size was modified with 0.03g/mL Fe(NO3)3·9H2O at 20?.deal with.After the modified materials were obtained,the difference in the treatment effect of the microcystins in the solution before and after the modification was compared by comparison experiments.The experimental results show that the modified attapulgite clay has a strong adsorption and removal effect on microcystins in solution,and can remove more than 90% of the microcystins in the solution,and the same with the unmodified attapulgite clay phase.In comparison,the removal effect of microcystins is improved,the treatment time is shortened,the pH value is applicable to a larger range,and the amount of dosing required for removal is reduced,which has a higher advantage.