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合成二硫氰基甲烷(即7012)的母液中含有硫氰根、氯根、及极少量的二硫氰基甲烷。通过测定硫氰根、氯根这两种离子的浓度变化来了解整个反映情况。硫氰根和氯根共存时,氯离子的化学测定法,由于两种离子性质相近,关健在于如何排除前者的干扰。一般可用某些氧化剂如高锰酸钾、二氧化铅,硝酸等把硫氰根破坏后测定氯根;也可先以银盐沉淀这种离子后再分离测定。据 Nordman报导用高锰酸钾溶液,能氧化大多数硫氰根,但同样氧化了少量氯根,带来误差。浓硝酸氧化的产物是硫酸根及残存的氰酸,均能与银盐反应,虽然硫酸银和氰酸银溶解于浓硝酸,但始终难以全部除尽硫酸银。在部分卤素离子存在时测定氯离子可使用 Feigle 氧化剂,对溴离子的分离是满意
The synthesis of dithiocyanomethane (ie 7012) in the mother liquor contains thiocyanate, chloride, and a very small amount of dithiocyanomethane. Through the determination of thiocyanate, chloride ion concentrations of these two changes to understand the entire reflection. Thiocyanate and chloride coexist, the chemical determination of chloride, due to the similar nature of the two ions, the key lies in how to rule out the interference of the former. Generally available for some oxidants such as potassium permanganate, lead dioxide, nitric acid, such as the determination of the destruction of thiocyanate chloride roots; may also be precipitated with silver salts after this ion separation and determination. According to Nordman, potassium permanganate solution is reported to oxidize most of the thiocyanate, but it also oxidizes a small amount of chloride to give errors. The products of concentrated nitric acid oxidation are sulfate and residual cyanic acid, both of which react with the silver salt. Although silver sulfate and silver cyanate are dissolved in concentrated nitric acid, it is always difficult to completely remove silver sulfate. Determination of chloride ion in the presence of some halogen ions Feigle oxidant can be used, satisfactory for the separation of bromide ions