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摘要：比較了幾種RoHS常用的六價(jià)鉻檢測標(biāo)準(zhǔn)，考察了萃取時(shí)間和萃取劑對鋼板涂鍍層中六價(jià)鉻含量測定結(jié)果的影響，闡述了各種六價(jià)鉻萃取方法的適用性。實(shí)驗(yàn)表明，沸水萃取法適用于可溶性六價(jià)鉻的萃取，弱堿蘋取法可用于兩性金屬涂鍍層。分析了目前鋼板涂鍍層表面六價(jià)鉻檢測方法中存在的問題，探討了六價(jià)鉻限制法規(guī)的符合性問題。
關(guān)鍵詞：鋼板；涂鍍層；六價(jià)鉻；測定；萃取；沸水；堿；RoHS指令
中圖分類號：TGl78 文獻(xiàn)標(biāo)志碼：A
文章編號：l004—227X(2009)02—0028—03
Comparison between the methods for determining hexavalent chromium in steeI sheet coatings／／CHEN Gui-lin+，KONG Ralene，QIAN Eric，ZHU Ping
Abstract：Some commonly．used standards for determining hexavalent chromium were compared．The effects of extraction time and extracting agent on the determination of hexavalent chromium content in coatings on steel sheets were studied．The applicability of individual method for extracting hexavalent chromium was expatiated．The experimental results showed that boiling water extraction is suitable for testing soluble hexavalent chromium compounds and weak alkaline extraction suitable for amphoteric metal coatings．The problems existing in present test methods for determination of hexavalent chromium in steel sheet coatings were analyzed．The compliance of RollS directive was discussed．
Keywords：steel sheet；coatin9；hexavalent chromium； determination；extraction；boiling water；alkaline；RollS directive
First．author’s address：Centre Testing International． Shenzhen 518101．
1 前言
歐盟RoHS指令(Directive 2002／95／EC The restriction of the use of certain hazardous substances in electrical and electronic equipment)以及中國的《電子信
息產(chǎn)品污染控制管理辦法》(即中國RoHS)對電子產(chǎn)品中六價(jià)鉻等6種有害物質(zhì)作了限制規(guī)定。鋼板在電子行業(yè)中廣泛應(yīng)用，傳統(tǒng)的電鍍和其他表面處理工藝，尤其是鉻酸鹽鈍化，對環(huán)境產(chǎn)生巨大影響。為了滿足各類法規(guī)的要求，企業(yè)積極開發(fā)無鉻工藝，努力實(shí)現(xiàn)環(huán)保產(chǎn)品。但是，針對金屬表面或涂鍍層表面六價(jià)鉻的測試方法目前尚無法統(tǒng)一，而且測試結(jié)果又難以滿足RoHS指令對六價(jià)鉻0．1％的限值要求。本文考察了目前使用較廣的六價(jià)鉻檢測方法在測定鋼板涂鍍層表面六價(jià)鉻時(shí)的差異性和適用性，以及影響測定的因素，并探討了RoHS中金屬涂鍍層表面六價(jià)鉻符合性問題。
