D_2EHPA对高浓度盐酸介质中钛的萃取

Solvent extraction of tetravalent thitanium from high concentration of acidic chloride solutions by D2EHPA

研究了D2EHPA对盐酸介质中钛的萃取和反萃性能。研究结果表明:萃取液中钛以TiOCl2.2D2EHPA的形式存在。钛萃取率随无机相中氯离子浓度和有机相中萃取剂浓度的增加而增加。D2EHPA对钛的饱和承载量为8.98 g/100 g D2EHPA。红外光谱研究进一步表明了Ti-D2EHPA螯合物的性质。在0.5～12 mol/dm3的盐酸介质中,D2EHPA对钛的萃取率随盐酸介质浓度的增加而增加,而对铁、铝、钙、镁无萃取性能。以7%H2O2+3 mol/dm3H2SO4为反萃剂,有机相中的钛可实现一次完全反萃。

The solvent extraction and stripping of titanium （ Ⅳ ） from acidic chloride solutions by DE EHPA （di-2- ethylhexyl phosphoric acid） in kerosene has been investigated. The solvent extraction results show that the dissolved titanium is present as TiOCl2·2D2EHPA. The extractability of titanium （ Ⅳ ） increases with the increase of the total chloride concentration in the aqueous phase and the extractant concentration in the organic phase. The loading capacity of DEEHPA for titanium（ Ⅳ ） is 8.98 g/100 g D2EHPA. IR spectroscopy is used to study the extracted complex in order to further clarify the nature of extracted complex. The results show that, the extractability of titanium （ Ⅳ ） increases when the concentration of hydrochloric acid aqueous solution increases from 0. 5 mol·dm^-3 to 12 mol·dm^-3. On the other hand,iron （ Ⅲ ） , aluminum （ Ⅲ ）, calcium （ Ⅱ ） and magnesium （ Ⅱ ） are not extracted under the same experimental conditions. Titanium（ Ⅳ ） can be completely stripped from the metal loaded organic phase with 7% H2O2 in 3 mol·dm^-3 H2SO4 as the stripping agent.