Study on Pressure Acid Leaching Technique of a Refractory High Silicon Zinc Oxide Ore

The effects of initial acid value,leaching temperature,still pressure,leaching time and liquid-solid ratio on the leaching rate of Zn and SiO2 and product liquid rate were analyzed under pressure acid system with a high silicon zinc oxide ore as the object of study.The results show that on the conditions that the ore samples in which the particle size is-0.105 mm above 85%,the initial acid value is 90.16 g/L,leaching temperature is 120 ℃,still pressure is 1.2 MPa,leaching time is 90 min,liquid-solid ratio is 5∶1 and the rate of agitation is 550 r/min,the leaching rate of Zn is 98.54% and the leaching rate of SiO2 is below 1.02% respectively,and the product liquid rate is no less than 941 L/(m2·h).Analyses on the leaching products by XRD and SEM indicate that through leaching process the surface of leach residues differs much from that before leaching.