Optimization of Indium Recovery and Separation from LCD Waste by Solvent Extraction with Bis(2-ethylhexyl) Phosphate (D2EHPA)

Table 6

Single stage batch test of extraction, washing, and stripping. Aqueous phases were 1 M H₂SO₄ (extraction and scrubbing) and 1 M HCl (stripping). The organic phase was 0.25 M D2EHPA diluted in kerosene with 2% 1-decanol.

Metal ion	Wt % in aq. phase after extraction	Wt % in aq. phase after scrubbing	Wt % stripped into aq. phase	Wt % remains in the organic phase
	(1 M H2SO4)	(1 M H2SO4)	(1 M HCl)
Al(III)	98.4 ± 1.0%	1.0 ± 0.4%	0.4 ± 0.1%	<1.7%
Cu(II)	98.8 ± 0.8%	0.2 ± 0.1%	0.1 ± 0.1%	<1.8%
Fe(III)	19.8 ± 2.5%	1.9 ± 0.1%	1.0 ± 0.1%	73.3 ± 2.7%
In(III)	0.8 ± 0.2%	0.7 ± 0.1%	95.7 ± 0.2%	2.8 ± 0.5%
Sn(IV)	2.9 ± 1.3%	0.3 ± 0.2%	0.1 ± 0.1%	96.7 ± 1.7%
Zn(II)	99.4 ± 0.1%	0.2 ± 0.1%	0.1 ± 0.1%	<0.6%