Recycling of arsenic residue and waste soda-lime silicate glass via vitrification

Vitrification is an environmental friend way to solidify arsenic residue (AR). In this work, instead of solidification/stabilization (S/S), we further explored the feasibility of recycling AR and waste soda-lime silicate (SLS) glass via vitrification. First, the purified AR (5–25 wt%) and waste SLS glass were melted in a closed electric furnace and successfully quenched to glass sheets. To verify the thermal, mechanical, and chemical stability of the prepared As-containing SLS glass samples, differential scanning calorimetry (DSC), nanoindentation, and water leaching experiments were performed, respectively. Results show that, with the increase of As concentration, the phase-separation phenomenon was enhanced and glass structure stability was decreased due to the formation of [AsO ₄] tetrahedral units (replacing [SiO ₄]). Nevertheless, all the recycled As-containing SLS glass samples remain amorphous and own comparatively high visual transparency (>86%), nano-hardness (> 7 GPa) and elastic modulus (> 80 GPa). Moreover, based on the dynamic and static water leaching experiments, the recycled glass sample containing 5 wt% of purified AR shows the lowest amount of leaching As (1.38 mg/L at 22±3 °C for 313 days) which has the potential for future application including building windows.