A New Method For The Separation And Extraction Of Vanadium From Stone Coal

Vanadium was separated from stone coal by roasting with sodium salt in conven -tional technology. Many new methods which contained roasting with calcium salt or roasting with compound additive appeared in recent years. Although they reduce the pollution of the conventional method this kind of methods also need very long time and high temperature. Therefore it is important to find a new method which can be used in low temperature and only need little time.Microwave was used in this paper with wet chemical separation method. First of all stone coal was triturated to 0.074 mm, and then it was treated with microwave for 30 minutes. It was found that the surface of stone coal which had been put in microwave was different through the SEM images. The S_bet of the stone coal increased to 16.2 m²/g from 9.6m²/g. There were caloric effect and non-caloric effect when the liquor was in microwave radicalization. The temperature of the liquor increased very fast when it was under microwave radiation. It need only 2 minutes for microwave in the condition of 400W to make the temperature to 100℃,but electric cooker need at least 10 minutes in the same way. The conductance of the liquor increased 20% when it was under the microwave radiation for 20 minutes. The optimal extraction condition was that time 40 minutes, S/L 1:5, H₂SO₄ 0.6mol/L and microwave power 600W, and the recovery of vanadium can reach to 70%.Ultrasonic was also used in the experiment with wet chemical separation method and it had cavitation effect on the liquor. Put the stone coal triturated to 0.074mm into the ultrasonic field of 200W. After 40 minutes .it was found that the surface of the stone coal was different from before through the SEM images. The S_bet increased to 12.1m²/g from 9.6m²/g. The optimal extraction condition was 80℃,H₂SO₄ 0.6mol/L, time 40min and ultrasonic power 250W,and the recovery of vanadium can reach to 66%.Microwave and ultrasonic field were used in this paper and it was significative that the two new methods reduced the pollution , cut downthe cost and decreased the time more. The process time was 1/10 oftraditional technology in Microwave field and 1/6 of traditionaltechnology in ultrasonic field.