Kinetics of iron removal from quartz under ultrasound-assisted leaching

High Temperature Materials and Processes

Yang Chang-Qiao¹  Li Su-Qin² 

[1] National-Provincial Joint Engineering Research Center for Comprehensive Utilization of Symbiotic-Associated Mineral Waste Resources in Bayan Obo, Inner Mongolia University of Science and Technology, Baotou, 014010, China;School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China;

关键词: highly pure silica;    oxalic acid;    shrinking core model;    activation energy;    mathematical model;   

DOI  :  10.1515/htmp-2020-0081

来源: DOAJ

【 摘 要 】

Kinetics of iron removal from quartz under the ultrasound-assisted leaching was explored in this paper, and the effects of temperature, leaching time, stirring speed and ultrasonic input power on iron removal were studied. The results revealed that the reaction kinetics followed the shrinking core model and the product layer internal diffusion was the rate-determining step in the ultrasound-assisted leaching process. The activation energy of the ultrasonic-assisted leaching reaction was 27.72 kJ/mol, which was 7.28 kJ/mol higher than that of the regular method. Moreover, the kinetic equation and mathematical model of iron removal from quartz were established. Compared with the regular leaching, only 40 min were required for the ultrasound-assisted leaching process to achieve an iron removal rate of up to 74%. Under the optimal parameters, SiO2 content of concentrate increased from 99.5828% to 99.9047%, and Fe2O3 content reduced from 0.0857% to 0.0223%. Additionally, it was found that the iron removal rate increased with increasing temperature, stirring speed or ultrasonic power.

【 授权许可】

Unknown