LAUSR

The forms of arsenic (As) and lead (Pb) in coal have an important influence on their transformation during combustion. Considering that As and Pb in coal are partially associated with pyrite, pyrolysis and oxidation experiments were conducted on pyrite in a fixed-bed reactor between 600 and 1000 °C to study the transformation of As and Pb in pyrite during thermal conversion. During pyrolysis, As remained essentially unreleased below 700 °C, and the release ratio increased with increasing temperature above 700 °C. At 1000 °C, As was almost completely released into the gas phase. During oxidation, As remained essentially unreleased below 800 °C, and the release ratio increased with increasing temperature above 800 °C, reaching 61.67% at 1000 °C. The gas-phase release ratio of As showed a dynamic change that rapidly increased with time, and the change was significantly correlated with the dynamic transformation of the pyrite. During pyrolysis, As was released into the gas phase by a two-step decomposition of...