Experimental Study On Technology Of Vanadium Extraction From Silicate-type Vanadium Ore

Vanadium is an important strategic resource and of broad application.China is a country of rich vanadium resources.Among these resources,silicate-type vanadium ore is of the character of high SiO₂ content.In traditional technology process,it is prone to agglomeration in calcination,lower vanadium dissolution rate and lower level of enrichment.So developing a new process for this ore,improving the utilization of these resources is of great significance.In this papers,the extraction of vanadium was studied that related to some silicate-type vanadium ore of Shaan' xi province.Based on the detective test,the main process is determined as primary roasting→secondary roasting with additive→acid-leaching→ion-exchange→depositing vanadium with ammonium. The research is mainly focused on roasting,leaching,ion-exchange,depositing vanadium.From the test results,it is found that the suitable leaching parameters are as following:the primary roasting temperature is at 700℃,the primary roasting time is 3h, the grinding fineness is 80%less than 200 mesh,the 1^# additive is 7%,the secondary roasting temperature is at 800℃,the secondary roasting time is 3h,the concentration of HCl is 3%,the leaching temperature is 70℃,the leaching time is 0.5h,the ratio of liquid-solid is 1:1.And the leaching rate is higher than 85%.Enriching the vanadium with 201×7 exchange resin,the suitable conditions of adsorption is given as following:the velocity of flow at 2.42mL/h,the concentration of V₂O₅ at 5.02g/L,pH value at 10.0.As a results,adsorption rate reached higher than 99%. The suitable conditions of desorption are:the concentration of NaCl at 10%,the velocity of flow at 2.0 mL/h,pH value at 10.0.And the desorption rate is higher than 99%.The rational conditions of vanadium precipitation are also determined as: stirring depositing vanadium time for 3h,using the(NH₄)₂SO₄,and the concentration at 1.2g/L,the washing water amount at 100mL.And precipitation rate of vanadium reached higher than 98%.Based on the study,a feasible process with rational parameters is suggested.The effective use of the vanadium resources can be reached.This will of great reference significance to vanadium extraction of silicate-type vanadium ore.