摘要
采用硼酸、柠檬酸和3种商品无铵盐或低铵盐脱灰剂对浸灰牛皮进行脱灰,从浴液pH、裸皮脱钙率和废水总氮浓度等方面,考察了这些材料的脱灰性能。结果表明:硼酸的pH缓冲性能好,但脱钙能力低于硫酸铵;柠檬酸的脱钙效果优于硫酸铵,但脱灰液的pH值低于5,可能导致裸皮损伤。硼酸或柠檬酸与铵盐配合使用时,可以改善脱灰体系的脱钙效果和缓冲性能。商品低铵盐脱灰剂的脱钙率和pH缓冲性能与硫酸铵很接近,但废水中的总氮含量仍然较高;商品无铵盐脱灰剂可以显著降低废水中的总氮含量,但脱钙率和pH缓冲性能较差。硼酸、柠檬酸和商品无铵盐或低铵盐脱灰剂的渗透能力均不及铵盐,故用这些材料脱灰时宜采用片灰皮工艺。
Boric acid,citric acid and three commercial non-/low-ammonium deliming agents were used for deliming of limed cattle hide.The deliming efficiency of these chemicals were determined in terms of pH of deliming float,the removal extent of calcium in pelt and the concentration of total nitrogen in effluent.The results indicate that boric acid has a good pH buffer action in deliming liquor,but its calcium removal extent is lower than that of ammonium sulphate.Compared with ammonium sulphate,citric acid has a higher calcium removal extent,but it results in a low pH of deliming float（pH5.0） that may lead to damage of pelt.The calcium removal extent and the pH buffering property of boric acid and citric acid can be improved when co-used with a proper amount of ammonium sulfate.The commercial low-ammonium deliming agent has a calcium removal extent and pH buffer action comparable to ammonium sulfate,but it still leaves a considerable amount of total nitrogen in effluent.The two commercial non-ammonium deliming agents can remarkably reduce total nitrogen in effluent,but their calcium removal extent and pH buffer action are relatively poor.In general,the total nitrogen concentration in effluent can be significantly decreased by using boric acid,citric acid and commercial non-/low-ammonium deliming agents.However,compared with ammonium sulfate,all these chemicals exhibit poorer penetrating action through the pelt.Therefore,the technique of limed pelt splitting should be chosen when these chemicals are employed.
出处
《中国皮革》
CAS
北大核心
2011年第1期12-15,共4页
China Leather
基金
国家科技支撑计划(2006BAC02A09)资助项目
关键词
制革
脱灰
无铵盐脱灰剂
脱灰剂
氨氮
leather making
deliming
non-ammonium deliming
deliming agent
ammonia nitrogen
