论文部分内容阅读
在钢铁分布中常遇到微量钨的没定,岩石分析中微量钨的测定也偶尔遇到,钨含量在0.5%以下时重量法容量法均不适用,其他适用于微量钨测定的方法也不多。常用的方法为硫氰酸钠一氯化亚锡比色法,二硫酚比色法和极谱法。硫氰酸钠法系以硫氰酸钠和新配制的氯化亚锡溶液为试剂,在8.5-9.5N盐酸溶液中钨显示黄色,可在20分钟后进行比色。此法适用的范围为0-0.85％W,绝对误差在±0.01％之内,铁和小量的铝、锑、铋、铅、锰、钛、锆等离子不发生
In the steel distribution often encountered in the determination of trace amounts of tungsten, rock analysis of trace tungsten is also occasionally encountered, tungsten content below 0.5% gravimetric volume method are not applicable to other methods for the determination of trace tungsten is not much . Commonly used methods are sodium thiocyanate-stannous chloride colorimetry, dithiol colorimetry and polarography. Sodium thiocyanate method is based on sodium thiocyanate and freshly prepared stannous chloride solution as a reagent. Tungsten is yellow in 8.5-9.5N hydrochloric acid solution and colorimetric after 20 minutes. This method is suitable for the range of 0-0.85% W, the absolute error within ± 0.01%, iron and a small amount of aluminum, antimony, bismuth, lead, manganese, titanium, zirconium plasma does not occur