HONG Xiuping1,2，LU Shuai1,2，LIANG Handong1,2，CUI Yukun1,2，ZHANG Yin1,3
(1. State Key Laboratory of Coal Resources and Safety Mining，CUMTB，Beijing 100083, China；
2. College of Geoscience and Surveying Engineering，CUMTB，Beijing 100083；
3. School of Chemical and Environmental Engineering，CUMTB，Beijing 100083)
Abstract: The dynamic leaching experiments and static immersion were carried out by using solution with different pH in order to investigate behaviour and fluorine concentration with different leachates;fluorine contents in residual after leaching were measured by fluoride ion-selective electrode. Results show that pH,leaching time and the modes of occurrence have great influence on leaching behavior of fluorine. The maximum concentration of fluorine,fluorine total quantity released soil and leaching rate increase with increasing acidity of leaching solution and fluorine leaching mainly concentrates within 60 h in the early stage of leaching. With increasingleaching time,fluorine released from soil decreases. Fluorine content dissolved and leaching rate of dynamic leaching are both higher than that of static immersion. This may be due to the stronger molecular motion of dynamic leaching which prompt the leaching solution fully infiltrating into the soil matrix. Leaching curves of yellow soil, yellow brown earths, paddy soil under the solution of pH=3 indicate that soluble fluoride saltcan be released during the leaching process and the more the soluble salt is, the more fluorine will be released.
Key Words: soil; fluorine; dynamic leaching; dissolved characteristics
EARTH AND ENVIRONMENT Vol. 43, No.3, Tot No.305, 2015, Page 356-362
