| 摘要 |
<p>A sulphur-containing iron ore, e.g. pyrites, is desulphurized to render it suitable for use as a gas purification agent by roasting it for between 10 seconds and 6 minutes at a temperature between 550 DEG and 850 DEG C. under oxidizing conditions, the time of roasting being so chosen that substantially no shrinking of the ore takes place. "Shrinking" is defined as cohesion of the oxide formed to a slag-like form. The roasting can be carried out between 550 DEG and 600 DEG C. in a rotary furnace or between 750 DEG and 850 DEG C. in a fluidizing furnace. If the gas to be purified contains hydrogen cyanide the oxide is treated with water or an aqueous solution of a base, preferably an alkali metal hydroxide, carbonate or bicarbonate or ammonia and the water or aqueous solution removed by filtration. After roasting and any further treatment the ore may be granulated with a binding agent, e.g. sulphite lye, and/or a filler, e.g. saw dust and/or lime slurry. German Specification 818,545 is referred to.</p> |
