Lead extraction from waste funnel cathode-ray tubes glasses by reaction with silicon carbide and titanium nitride.
As a possibility to clean waste CRT glass, treatment of lead-containing glass with a reducing agent, SiC or TiN, leads to a porous material containing metallic lead, Pb(0), located on the surface of the pore, and unreduced lead, Pb(II). The influences of reducing agent content, of the time, and at last of the temperature on lead reduction were analysed. Our investigations have pointed out significant differences as a function of the used reducing agent. CRT glass heat treated with SiC lead to less Pb(0), compared to TiN as shown by X-ray diffraction, and differential scanning calorimetry (DSC). It has been also evidenced that lead reduction occurs on randomized zones inside the sample leading to macroscopic lead beads inside glassy samples. XPS and XAS measurements were also carried out to investigate the local structure of lead and have evidenced a change of role of lead inside the glassy framework in function of the used conditions.
Yot
Pascal G
PG
Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2-ENSCM-UM1, CC 1503, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France. pascal.yot@univ-montp2.fr
Méar
François O
FO
D002152:Calorimetry, Differential Scanning / Q000379:methods; D017554:Carbon Compounds, Inorganic / Q000737:chemistry*; D016288:Computer Terminals; D003247:Conservation of Natural Resources; D004581:Electronics; D004785:Environmental Pollutants / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005898:Glass; D006256:Hazardous Waste; D007854:Lead / Q000737:chemistry / Q000302:isolation & purification*; D012037:Refuse Disposal; D017655:Silicon Compounds / Q000737:chemistry*; D013696:Temperature; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction; D014965:X-Rays
D017554:Carbon Compounds, Inorganic; D004785:Environmental Pollutants; D006256:Hazardous Waste; D017655:Silicon Compounds; D007854:Lead; C041500:titanium nitride; D014025:Titanium; C022088:silicon carbide