Removing As, Ba, Cu and Zn from Waste Plasma Display Panel Glass by Electrokinetics

Abstract

Due to shorter and shorter life span and the rapid development of flat panel display, plasma display panel (PDP) is now becoming a new kind of e-waste. In order to remove heavy metals, such as As, Ba, Cu, Zn, from waste PDP glass, electro-kinetic process was introduced and factors that affect heavy metal removing rate were investigated. Results showed that HNO3 concentration and PDP adding amount could significantly impact heavy metal removing rate, while current density was on the opposite. Heavy metal removing rate increased first and then decreased as the time extension. When PDP powders was 2 g, 9 mL 5 mol/L HNO3 was added, current density was 200 mA/cm2 and time was 6 h, the removal rate of As, Ba, Cu, Zn were 71.02%, 95.87%, 92.50% and 97.70%, respectively. As, Ba, Cu and Zn distributions in the cathode, anode and middle chamber varied as changing particle size, HNO3 concentration, current density. Generally, most Cu was concentrated in cathode chamber, and Zn in the anode chamber, while As and Ba would be in both cathode and anode chamber. As, Ba, Cu and Zn, in the middle chamber, no more than 10%, were the lowest among the three.