氧化木薯淀粉丁二酸酯-g-丙烯酸乙酯的制备及其吸附性能

Preparation of oxidized cassava starch succinate-g-ethyl acrylate and its adsorption capability

以木薯淀粉为原料,在氧化木薯淀粉的基础上,以丁二酸酐为酯化剂、对甲苯磺酸为催化剂得到氧化木薯淀粉丁二酸酯(OCSS),进一步以丙烯酸乙酯为接枝单体、过硫酸铵为引发剂得到氧化木薯淀粉丁二酸酯-g-丙烯酸乙酯(OCSS-g-EA)。在酯化剂加入量(相对于淀粉干基质量)为100%、酯化时间为3.0 h、酯化温度为35℃、催化剂加入量为3%的条件下,OCSS的酯化取代度可达0.133;在接枝时间为4.0 h、接枝温度为45℃、丙烯酸乙酯与淀粉干基的质量比为1.50∶1、引发剂浓度为50 mmol/L的条件下,OCSS-g-EA的接枝率和接枝效率分别可达67.02%和41.93%。OCSS-g-EA的吸油率达84.37%,对污水COD的吸附去除率达75%以上,对Cu^(2+)的吸附量可达19 mg/g,吸附性能优良。

On the basis of cassava starch oxidization,the oxidized cassava starch succinate(OCSS)was prepared using cassava starch as raw material,succinic anhydride(SA)as esterifying agent and p-toluenesulfonic acid as catalyst.Further,the oxidized cassava starch succinate-g-ethyl acrylate(OCSS-g-EA)was prepared using ethyl acrylate as graft monomer and ammonium persulfate as initiator.The substitution degree of OCSS reaches 0.133 under the conditions of esterifying agent amount(based on starch dry basis)100%,esterification time 3.0 h,esterification temperature 35℃,and catalyst amount 3%.The grafting rate and efficiency of OCSS-g-EA reach 67.02%and 41.93%,respectively,under the conditions of grafting time 4.0 h,grafting temperature 45℃,mass ratio of ethyl acrylate to starch dry basis 1.50∶1 and initiator concentration 50 mmol/L.The OCSS-g-EA product exhabits excellent adsorption capability with 84.37%of oil absorption rate,more than 75%of adsorption removal rate of COD in wastewater,and 19 mg/g of Cu^(2+)adsorption capacity.