以小龙虾壳为原料,按酸碱交替法生产的甲壳素,蛋白质和虾青素等物质流失于废水中,采用壳聚糖作絮凝剂,可将虾青素与蛋白质絮凝沉淀。试验结果表明:调节pH值6.0,每升废水中添加40 ml 1%壳聚糖醋酸水溶液,静置3 h,废水中溶液的透光率最低...以小龙虾壳为原料,按酸碱交替法生产的甲壳素,蛋白质和虾青素等物质流失于废水中,采用壳聚糖作絮凝剂,可将虾青素与蛋白质絮凝沉淀。试验结果表明:调节pH值6.0,每升废水中添加40 ml 1%壳聚糖醋酸水溶液,静置3 h,废水中溶液的透光率最低,絮凝物蛋白质回收率达88.6%。使用几种蛋白酶水解絮凝物,其中风味蛋白酶水解度最大,在初始pH值6.5,水解温度55℃,试验确定:选用风味蛋白酶1.5 g/kg絮凝物,固液比1:2时,保温酶解时间4 h,虾青素提取率可达4.49%。该条件下絮凝物蛋白质的水解度为23.8%。提取虾青素并将水解后的蛋白浓缩,喷雾干燥,制成水解动物蛋白,产品不苦,具有良好的风味。展开更多
Crayfish shell is an abundant natural waste and is also a potential biosorbent for pollutants,especially,heavy metals.In this study,the safety of the use of crayfish shell as a biosorbent was first assessed by release...Crayfish shell is an abundant natural waste and is also a potential biosorbent for pollutants,especially,heavy metals.In this study,the safety of the use of crayfish shell as a biosorbent was first assessed by release experiments involving primary heavy metal ions,such as Cu^(2+),Zn^(2+),and Cr^(3+),in aqueous solution under different environmental conditions.The release concentrations of heavy metals were dependent on pH,ionic strength,and humic acid;and the maximum release concentrations of heavy metals were still lower than the national standard.Specifically,Cu^(2+) and Pb^(2+) removal by crayfish shell in synthetic wastewater was investigated.The removal process involved biosorption,precipitation,and complexation,and the results indicate that crayfish shell is an excellent biosorbent for Cu^(2+) and Pb^(2+) removal.The precipitation step is particularly dependent on Ca species,pH,and temperature.The maximum removal capacities of Pb^(2+) and Cu^(2+) were 676.20 and 119.98 mg/g,respectively.The related precipitates and the generated complex products include Cu_(2)CO_(3)(OH)_(2),Ca_(2)CuO_(3),CuCO_(3),Pb_(2)CO_(3)(OH)_(2),CaPb_(3)O_(4),and PbCO_(3).展开更多
基金supported by the Key Special Program on the S&T for the Pollution Control and Treatment of Water Bodies(No.2017ZX07603-003)。
文摘Crayfish shell is an abundant natural waste and is also a potential biosorbent for pollutants,especially,heavy metals.In this study,the safety of the use of crayfish shell as a biosorbent was first assessed by release experiments involving primary heavy metal ions,such as Cu^(2+),Zn^(2+),and Cr^(3+),in aqueous solution under different environmental conditions.The release concentrations of heavy metals were dependent on pH,ionic strength,and humic acid;and the maximum release concentrations of heavy metals were still lower than the national standard.Specifically,Cu^(2+) and Pb^(2+) removal by crayfish shell in synthetic wastewater was investigated.The removal process involved biosorption,precipitation,and complexation,and the results indicate that crayfish shell is an excellent biosorbent for Cu^(2+) and Pb^(2+) removal.The precipitation step is particularly dependent on Ca species,pH,and temperature.The maximum removal capacities of Pb^(2+) and Cu^(2+) were 676.20 and 119.98 mg/g,respectively.The related precipitates and the generated complex products include Cu_(2)CO_(3)(OH)_(2),Ca_(2)CuO_(3),CuCO_(3),Pb_(2)CO_(3)(OH)_(2),CaPb_(3)O_(4),and PbCO_(3).
