氧瓶法测定难燃烧高硼有机物中的硼含量

DETERMINATION OF BORON IN DIFFICULTLY COMBUSTIBLE HIGH BORON-CONTAINING ORGANIC COMPOUNDS BY OXYGEN-FLASK

把有机硼定量地转变为硼酸是测硼的关键,常用氧瓶、氧弹和消化法进行分解。Gradskova,N.A.等用氧瓶法测硼,其准确性欠佳。Debal,E.指出消化法对测定低硼化合物比氧弹法更满意,但此法分解对强酸、强碱和强氧化剂特别稳定的具有笼状结构的B_(10)H_(10)^(2-)、B_(12)H_(12)^(2-)型主高硼化合物却不适用。氧瓶法具有简便、快速、清洁等优点,但只能测定很少样品,且燃烧不完全,因此,有用Ag_(2)B_(12)X_(12)重量法测定B_(12)X_(12)^(2-)(X=H,Br,Ⅰ)型化合物。

Difficultly combustible high boron-containing organic compounds are quantitatively burnt by adding anhydrous Na_(2)SO_(3) or Na_(3)SO_(4) as additive to form Na_(2)B_(4)O_(7) which is absorbed by dilute acid and transformed into H_(3)BO_(3).By the present procedure,the formation of B_(4)C can be avoided.This method is suitable for decomposition of many non-volatile B-containing organic compounds.