A novel process utilizing mechanochemical sulfidization to remove lead from cathode ray tube funnel glass

A novel process of mechanochemical sulfidization for the treatment of cathode ray tube (CRT) funnel glass has been investigated by co-grinding with the element sulfur. The ground samples were characterized by means of a set of analytical methods, including scanning electron microscopy (SEM), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and thermogravimetric analysis (TG). The analytical results showed that during the co-grinding of the CRT funnel glass with sulfur, the SiOPb bond in glass and SS bond broke and recombined into lead sulfide (PbS). The sulfidizing reaction proceeded with an increase in grinding time and the amount of the added sulfur. The sulfidizing rate increased rapidly from 16.6% for the 10-min ground sample to 96.7% for the 120-min ground sample. Using this process, current mineral processing technology, such as flotation separation, might be used to recover PbS. The proposed technology could also be used to treat other leaded glass and even other lead-containing wastes.