摘要
当共存大量非金属和金属离子(其中包括铌)时,作为钽的特效沉淀剂未见文献报道.梶山绿朗提出,用氯化四苯鉮盐酸(TPAC)在8mol·L以上氢氟酸介质中定量沉淀铌钽合量.作者曾在此基础上探索了铌钽分离.研究结果表明,在0.11—0.22mol·L的NHHF介质中铌钽分别以TaF和NbOF状态存在,TPAC只能与前者形成氟钽酸四苯鉮((CH)AsTaF,简称TPAFTa)离子缔合物沉淀,而后者不沉淀,从而使铌钽定量分离.本文以TPAC作为沉淀剂用重量法测定含铌复杂基体中钽的可能性.研究结果表明,TPAFTa经分解定量地转化为五氧化二钽,并以此为称量形式.对20多种共存离子的吸附或
A new gravimetric method has been developed for the quantitative determination of tantalum in a complex sample containing niobium by using tetraphenylarsonium chloride hydrochloride(TPAC)as a highly selective precipitant for fluorotantalate,namely through the formation of an ionic associate,(CH)AsTaF,which is a white needle with good thermal stability.It decomposes to tantalum pentaoxide after heating to 900℃.The coexistence of 20 foreign ions examined in the original sample shows no harmful effect in the determination of tantalum.Some physicochemical properties and physical constante of(CH)AsTaFhave been studied in detail and recorded.The recovery of tantalum was 98.1-101.8%and the result of analyses of a nickel-based alloy was 1.80±0.027%Ta.
出处
《化学学报》
SCIE
CAS
1988年第1期69-72,共4页
Acta Chimica Sinica
