摘要
黄钾铁矾是金属硫化物在酸性条件下氧化形成的主要次生矿物。很多研究表明,金属硫化物矿区广泛发育的氧化亚铁硫杆菌会影响金属硫化物的氧化分解和次生矿物的形成。为讨论氧化亚铁硫杆菌在黄钾铁矾形成过程中的作用,设计了两组平行实验制备黄钾铁矾:一种采用化学方法合成黄钾铁矾,另一种在相同条件下接种氧化亚铁硫杆菌合成黄钾铁矾。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱分析仪(EDS)等技术对两种实验获得的黄钾铁矾进行定性分析和形貌观察。结果表明:在氧化亚铁硫杆菌充分繁殖的条件下,细菌的参与更利于黄钾铁矾的形成;Fe2+的氧化速率可能是影响黄钾铁矾结晶的主要因素,氧化亚铁硫杆菌通过提高Fe3+的供应速度促使黄钾铁矾快速结晶,细菌作用下形成的黄钾铁矾结晶程度好于纯化学方法制备的黄钾铁矾。
Jarosite is a major secondary mineral formed in acid supergene environment by oxidation of metal sulphide. Thiobacillus ferrooxidans occurring extensively in metal sulphide ore district has an important effect on oxidation of metal sulphide and formation of secondary minerals. In order to discuss the effect of Thiobacillus ferrooxidans on the formation of jarosite, two parallel experiments were conducted for preparation of jarosite: chemical experiment and biologically mediated experiment. The compositions and morphological features of these two groups of jarosites have been investigated by means of XRD, SEM and EDS. The study indicates that full propagation of Thiobacillus ferrooxidans in the solution is beneficial to the formation of jarosite. The oxidation rate of Fe 2+ in the solution is probably the main factor that affects crystallization of jarosite. Thiobacillus ferrooxidans induces a rapid crystallization of jarosite by increasing the supply rate of Fe 3+ on the mineral surface. Jarosite mediated by Thiobacillus ferrooxidans has a better crystalline form than that synthesized by chemical method.
出处
《高校地质学报》
CAS
CSCD
北大核心
2005年第2期234-238,共5页
Geological Journal of China Universities
基金
国家自然科学基金项目(49673187)资助
关键词
氧化亚铁硫杆菌
黄钾铁矾
扫描电镜
形貌特征
成分分析
Thiobacillus ferrooxidans
jarosite
SEM
morphological features
compositional ayslysis
