Microcapsule And Nanogel Based On Sodium Alginate Gel For Cr(Ⅵ) And Pb(Ⅱ) Removal From Aqueous Solution

Rutin and quercetin belong to flavonoids compounds deriving from a wealth of sources.They are constatly used in the fields of medicin and food additives.Recently,the antioxidate activity of rutin and quercetin have drawn the atrention of researchers.Rutin and quercetin can also form complexes with metal ions such as copper,chromium ions.And the antioxidate activity of the complexes are usually higher the ligands.Sodium alginate is a natural binary copolymer with unique gel property and well adsorption capacity.And it has been wildly used in medical field.Recently,the microcapsule and nanogel based on sodium alginate also shows great application prospect in the area of environmental pollution treatment,which has also drawn the attention of many researchers.This paper is aimed at the preparation and characterization of microcapsule and nanogel based on sodium alginate,and further application in heavy metals removal.The specify results are as follows:(1)Rutin-Cr(III)alginate-chitosan microcapsule system(rutin-Cr(III)ACMS)was prepared with internal gelation technique.And the average diameter in wet condition is 235 μm.Rutin-Cr(III)complex showed higher antioxidant activity than ligand rutin ligand.The XPS data illustrated that rutin-Cr(III)complex was able to reduce Cr(VI)to Cr(III),and 91.45 % of Cr(VI)was reduced to Cr(III)at pH 1 in 3 h.Rutin-Cr(III)ACMS also showed good removal rate of Cr(VI),and 90.00 % of Cr(VI)was reduced at pH 1 in 22 h.Both the inner layer alginate gel and the outer layer chitosan kept the sustained release of rutin-Cr(III)complex;(2)Alginate nanoparticles(AN)and quercetin decorated alginate nanoparticles(Q-AN)were prepared with the approach of nano-emulsions coupled with external gelation.The diameter of AN and Q-AN were 95.06 nm and 58.23 nm respectively.A higher pH condition facilitated the adsorption of Pb(II).At pH 7,83.26 % and 90.07 % of total Pb(II)was absorbed by AN and Q-AN respectively.Adsorption and desorption experiments showed that Q-AN possessed higher adsorption rate,adsorption capability and desorption rate than AN.In conclusion,both the rutin-Cr(III)ACMS Q-AN prepared in this experiment were low-cost,environmentally friendly,and it showed promising application in fields of environment pollution treatment.