碱溶液提取-火焰原子吸收分光光度法对皮革中六价铬测定的适用性  

Applicability of Alkaline Digestion/flame Atomic Absorption Spectrometry for Determination of Hexavalent Chromium in Leather

作　　者：李沁阳 陈占光 周诚 黄彦杰 唐余玲[1] 周建飞[1,2] LI Qinyang;CHEN Zhanguang;ZHOU Cheng;HUANG Yanjie;TANG Yuling;ZHOU Jianfei(National Engineering Research Center of Clean Technology in Leather Indusrty,Sichuan University,Chengdu 610065,China;The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education,Sichuan University,Chengdu 610065,China;China Leather Industry Association,Beijing 100000,China)

机构地区：[1]四川大学制革清洁技术国家工程研究中心,四川成都610065 [2]四川大学皮革化学与工程教育部重点实验室,四川成都610065 [3]中国皮革协会,北京100000

出　　处：《皮革科学与工程》2022年第1期63-67,共5页Leather Science and Engineering

基　　金：中国皮革协会资助项目“含铬皮革废碎料环境风险评估”(21H1135)。

摘　　要：为探究碱溶液提取-火焰原子吸收分光光度法对皮革中六价铬测定的适用性,选用国内典型制革厂的皮革样品,分别采用碱溶液提取-火焰原子吸收分光光度法(HJ 1082-2019)和磷酸缓冲液提取-二苯碳酰二肼分光光度法(GB/T 22807-2019)测定皮革样品中的六价铬,并进行对比分析。结果表明,在碱溶液提取-火焰原子吸收分光光度法中,碱溶液提取导致皮革样品水解,与胶原纤维结合的三价铬大量溶出,导致提取液中总铬浓度偏高,并且部分三价铬与水解的胶原多肽结合后形成铬-有机物络合物,难以被MgCl2屏蔽。同时,没有氮气的保护,导致溶出的三价铬被氧化成六价铬。此外,火焰原子吸收分光光度法不能有效区分测定三价铬和六价铬,与磷酸缓冲液提取-二苯碳酰二肼分光光度法相比,碱溶液提取-火焰原子吸收分光光度法对皮革样品中六价铬的测定结果明显偏高,该方法不适用于对皮革样品中六价铬含量的测定。This article explored the alkaline digestion/flame atomic absorption spectrometry for determination of hexavalent chromium in leather applicability.The hexavalent chromium in the leather samples from domestic typical tanneries were simultaneously determined using the alkaline digestion/flame atomic absorption spectrometry and phosphate buffer extraction-colorimetric method.The results indicated that the alkaline digestion could hydrolyze the leather samples and the trivalent chromium could dissolve from the combined collagen fiber,resulting the high total concentration of chromium in extraction solution.At the same time,some chrome-organic complexes,which hardly shield by MgCl2,were formed due to the combination of trivalent chromium with hydrolyzed collagen polypeptide.What’s worse,the dissolved trivalent chromium could be oxidized to hexavalent chromium without the protection of nitrogen.In addition,the flame atomic absorption spectrometry couldn’t effectively distinguish the trivalent chromium and hexavalent chromium,thus resulting higher test value of hexavalent chromium compared with phosphate buffer extraction-colorimetric method.Thus,the results indicated that the alkaline digestion/flame atomic absorption spectrometry is not suitable for the determination of hexavalent chromium content in leather.

关 键 词：皮革 六价铬 火焰原子吸收分光光度法 分光光度法 

分 类 号：TS57[轻工技术与工程—皮革化学与工程]