摘要
试样以HF溶解,H2SO4冒烟除尽HF和SiF4,灼烧,锂呈Li2SO4而称至恒量。试样中铁、镍、铬杂质用ICP AES法测定,从灼烧后的不纯Li2SO4质量中减去铁、镍、铬各氧化物的质量,计算锂的质量分数。考察了溶样、除硅、灼烧、扣除杂质量等条件,建立了锂硅合金中主成分锂及杂质铁、镍、铬的测定方法。锂的RSD(n=6)<0.5%;铁、镍、铬的RSD(n=6)均<5%。试样加标回收率,锂为99.3%～99.7%,铁为97.5%～105.0%,镍为95.0%～100.0%,铬为103.0%～106.0%。方法完全能满足Li13Si4合金的分析,也适合其它类型锂硅合金的分析。
Sample of Li-Si alloy in a platinum crucible was dissolved in HF ( ρ 1.15g·ml^(-1)) and then fumed with H_2SO_4 to dryness to expel silicon as SiF_4 and excess amounts of HF. The crucible with the salts of sample was then ignited at 800℃ for 3h in a muffle furnace. After cooling to room temperature in a desiccator, the crucible together with the ignited residue were weighed, and its mass was taken which was composed of Li_2SO_4 and oxides of iron, nickel and chromium as impurities, together with the mass of the erucible. The ignited residue was then dissolved with HCl(1+1) in the crucible, and the solution was diluted to 100ml in a volumetric flask with water. The contents of Fe Ni and Cr were then determined by ICP-AES, and their results were expressed as oxides. The mass of Li_2SO_4 was calculated by substracting the masses of Fe_2O_3, NiO and Cr_2O_3, denoting as m_2 m_3 and m _4 respectively, from the mass of impure Li_2SO_4 ( m _1). Recoveries obtained for Li Fe Ni and Cr were in the ranges of 99.3%～99.7%, 97.5%～105.0%, 95.0%～100.0% and 103.0%～106.0% respectively.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2003年第12期704-706,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
