Stabilization of Waste Mercury with Sulfide through the Ball-Mill Method and Heat Treatment

Abstract

Most mercury supplies nowadays are limited due to their toxicity and difficulty in treatment. If mercury is stored inappropriately, it will not only contaminate the environment but also pass along the food chain and eventually to humans. Therefore, addressing mercury waste is crucial for the environment and human health. This study aims to stabilize waste mercury using sulfur powder and generate mercury production through a ball mill and heat treatment. To begin with, sulfur powder, waste mercury (98%) from chemicals, and milling balls will be mixed in this step. The parameters in this process were milling temperature, milling time, ball/material ratio, and milling speed. Under the optimal parameters of 35 °C for milling temperature, 12 h for milling time, 46% for the ball/material ratio, and 300 rpm for milling speed, β-HgS was obtained, and α-HgS was subsequently acquired through dry distillation in a tubular furnace at 600 °C for 3 h. On the other hand, high-purity mercury (99.5%) could be recovered under the circumstances of heating α-HgS with oxygen at 600 °C for 3 h. In a nutshell, waste mercury (98%) could be treated appropriately under the state of α-HgS, and high-purity mercury (99.5%) could be produced and reused for other industries through this research. Both contribute to environmental remediation and resource recovery goals.