| 摘要 |
A process for the removal of pyrite from coal which comprises preparing an aqueous slurry containing finely-divided coal particles; adding to the slurry an alkali metal hydroxide selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide, as well as mixtures thereof, in amounts sufficient to continuously maintain the pH of the slurry at a value of below about 8; agitating the slurry while treating the slurry with oxygen or an oxygen-containing gas to convert the pyrite in the coal to a soluble alkali metal sulfate; reacting lime with the so-formed alkali metal sulfate to regenerate the alkali metal hydroxide and then recycling the hydroxide for use in the process. |
