Lead recovery from cathode ray tube funnel glass with mechanical activation

Figures & data

Table 1. Chemical composition of the end-of-life CRT funnel glass analyzed by X-ray fluorescence (XRF)

Oxides	wt%
SiO2	53.90
PbO	23.10
K2O	7.59
Na2O	5.81
CaO	3.06
Al2O3	3.03
MgO	1.86
Fe2O3	0.42
SrO	0.41
BaO	0.35
Other trace elements	0.47

Figure 1. SEM images of CRT funnel glass after mechanical activation for 2 hr at different rotational speeds under an ambient atmosphere: (A) raw material; (B) 100 rpm; (C) 300 rpm; (D) 500 rpm; (E) 700 rpm.

Figure 2. X-ray diffraction patterns of raw material and 120-min-activated CRT funnel glass at different rotational speeds.

Figure 3. Dependence of recovery rate of major elements on milling rotational speed, under the following conditions: leaching temperature of 95 °C, HNO₃ concentration 3 mol/L, and leaching time of 1 hr.

Figure 4. Dependence of recovery rate of major elements on activation time, under the following conditions: leaching temperature at 95 °C, HNO₃ concentration 3 mol/L, and leaching time of 1 hr.

Figure 5. Dependence of recovery rate of major elements on the leaching temperature, under the following conditions: leaching time of 1 hr and HNO₃ concentration 3 mol/L.

Figure 6. Dependence of recovery rate of major elements on the acid concentration, under the following conditions: leaching time for 1 hr and temperature at 95 °C.

Figure 7. Dependence of recovery rate of major elements on the liquid-to-solid ratio, under the following conditions: HNO₃ concentration 3 mol/L, leaching time of 1 hr, and temperature at 95 °C.

Figure 8. Dependence of recovery rate of major elements on the leaching time, under the following conditions: HNO₃ concentration 3 mol/L and leaching temperature at 80 °C.

Figure 9. Photo and XRD pattern of residue after leaching in 3 mol/L HNO₃ at 95 °C for 1 hr (L/S = 150). (Color figure available online).

Figure 10. O1s, Si2p, and Pb4f spectra of unactivated, activated, and leached samples.