胶原羧基含量对铬吸收性能影响的研究  

Influence of Collagen Carboxyl Groups Content on Chromium Absorption

作　　者：夏淳淳[1] 罗朝阳[1] 范浩军[1] 李成霞[1] 

机构地区：[1]四川大学制革清洁技术国家工程实验室,四川成都610065

出　　处：《中国皮革》2011年第5期18-22,共5页China Leather

基　　金：国家自然科学基金资助项目(20976110)

摘　　要：用氯乙酸对皮粉进行接枝改性以提高胶原羧基含量,研究胶原羧基含量对铬吸收率的影响。结果表明:在303K,pH值为4.0条件下,与空白样相比,改性皮粉对铬吸收量w(Cr3+)/w(皮粉)从14.01mg/g提高至22.31mg/g。在pH值为4.0,298、303、308、313、318K条件下,改性皮粉对铬的吸收量分别为20.74、22.31、24.80、27.27、34.65mg/g,升高温度有利于铬的吸收。根据高吸收机理可知:氯乙酸与胶原上的氨基发生化学反应,将羧基引入胶原分子链中,则在吸收过程中,氯乙酸引入的羧基与胶原原有的羧基共同与三价铬配位,从而增进了铬的吸收。Chloroacetic acid with carboxyl groups were applied for modification of collagen. As a result, the additional car- boxyl groups were introduced onto the backbone of collagen and extra combining point for chromium tanning agents was achieved. Hide powder modified with chloroacetic acid could adsorb 22.31 mg/g chromium from an aqueous solution at pH 4.0, which is higher than the adsorption of un - modified hide powder （ 14.01 mg/g）. The adsorption capacity of hide powder is found to depend on the temperature and higher temperature is beneficial for the absorption of chromium, for example, a maxi- mum adsorption capacities of 20.74rag/g, 22.3ling/g, 24.80mg/g, 27.27mg/g and 34.65mg/g are observed at 298K, 303 K, 308 K, 313 K and 318 K, respectively. The adsorption of chromium could be divided into two steps： a primary rapid step and a secondary slow step. The rapid step lasted for about 2h and 52% chromium adsorption iscompleted in this rapid step. The maximum chromium adsorption of 32.28mg/g is achieved after 4hrs. The high exhaustion chromium mechanism of modified hide powder is suggested to be that： chloroacetic acid reacts with collagen and forms firm covalent bond firstly, and then the additional carboxyl groups of chloroacetic acid are introduced onto the backbone of collagen. In the adsorption process, the introduced carboxyl groups together with carboxyl groups of collagen coordinated with chromium, which contributed to the hide pow der high chromium absorption.

关 键 词：胶原 侧基修饰 羧基含量 高铬吸收 

分 类 号：TS51[轻工技术与工程—皮革化学与工程]