论文部分内容阅读
此类硅酸盐主要作电焊条等原材料用,要求含磷量不超过0.04%。试样用氢氟酸,硝酸溶解,然后以钼酸铵,铋盐——抗坏血酸为发色剂测定磷(本刊1973年第二期球墨铸铁系统分析)。试样中大量Al~(3+)、Fe~(2+)、K~+、Na~+、Cu~(2+)、Mg~(2+)等均不干扰测定。钛的干扰由于 F~-存在而消除。少量 F~-干扰磷的测定,可加硼酸掩蔽。硼酸的存在对吸光值影响很小。硅酸盐中的磷一般均以磷酸盐状态存在,故不必再氧化。称取研细试样0.5000克置于铂蒸发皿中,加少许水润湿,加40%氢氟酸10毫升,浓硝酸5毫升,加
Such silicate is mainly used for welding electrodes and other raw materials, requiring less than 0.04% of phosphorus content. Samples with hydrofluoric acid, nitric acid dissolved, and then ammonium molybdate, bismuth salt - ascorbic acid as a chromogenic reagent Determination of phosphorus (published in 1973 second ductile iron system analysis). A large amount of Al 3+, Fe 2 +, K +, Na +, Cu 2 +, Mg 2+ in the sample did not interfere with the determination. Titanium interference is eliminated due to F ~ -. A small amount of F ~ - interference phosphorus determination, boric acid can be added to cover. The presence of boric acid has little effect on the absorbance. Phosphorus in silicate are usually phosphate state, so no need to re-oxidation. Weigh fine test sample 0.5000 grams placed in platinum evaporating dish, add a little water wet, add 40% hydrofluoric acid 10 ml, concentrated nitric acid 5 ml, add