用钒(V)-PAR-NH_2OH-DDMAA混合显色体系测定钒

DETERMINATION OF VANADIUM WITH VANADIUM(V)-PRA-NH2OH-DDMAA MIXED COLOUR SYSTEM

研究了钒(V)-PAR-羟胺-DDMAA(Dodecyldimethylamino acetic acid)混合显色配位体系的特性.该体系在0.5～0.9mol/L硫酸溶液介质中,其最大吸收峰λ_(max)为560nm波长处,在560nm波长处空白值几乎等于零,摩尔吸光系数∈_560为3.7× 10~4L·mol^(-1)·cm^(-1).配合物的组成比,V(v):PAR:NH_2OH:DDMAA为1:1:1:1:1.0～30μgV^(5+)+/25ml范围内.服从比尔定律,用该方法直接测定钨精矿和钨矿中微量钒,获得了满意的结果.

The spectrophotometric properties of Vanadium(V)-PAR-NH2OH-Doecyldimethylamino acetic acid(DDMAA)mixed colour ligand system were studied, the system has its absorption maximum at 560nm with the range of 0. 5~0. 9 mol/L sul-furic acid solution, the molar absorptivity is 3. 7×104L ×mol-1, cm-1 at λmax=560nm and the blank correction at 560nm approaches to zero. Composition ratio is V(v): PAR:NH2OH:DDMAA = l:l:l:l. Beer's law is obeyed in the range of 0~ 30μV5+/25ml. This method has been direct determination of trace vanadium yn tungsten concentrate and wolframite,with proves satisfactory results.