(九江學(xué)院 化學(xué)與環(huán)境工程學(xué)院,九江 332005)
摘 要: 以典型硅酸鹽細(xì)菌Paenibacilluspolymyxa和Agrobacterium tumefaciens及真菌Aspergillus niger為試驗(yàn)菌株,采用搖瓶培養(yǎng)試驗(yàn),通過測(cè)定發(fā)酵培養(yǎng)液中細(xì)菌濃度、pH值、浸礦上清液中K、Si、Al的質(zhì)量濃度以及鉀長(zhǎng)石被菌株作用前后的SEM和XRD分析,比較了這三種典型種類微生物對(duì)鉀礦物的動(dòng)態(tài)溶蝕效果。結(jié)果表明:真菌的生長(zhǎng)周期較硅酸鹽細(xì)菌的短,且具有更高的產(chǎn)酸能力,但硅酸鹽細(xì)菌的對(duì)數(shù)生長(zhǎng)期相對(duì)較長(zhǎng),其在培養(yǎng)液中具有更高的細(xì)菌濃度,產(chǎn)生胞外多聚物的能力更強(qiáng);三株菌種對(duì)鉀長(zhǎng)石均有一定的風(fēng)化分解能力,Paenibacilluspolymyxa的溶蝕效果最好,浸出液中的K2O、SiO2、Al2O3的質(zhì)量濃度最高可達(dá)2.30 g/L、6.55 g/L、5.20 g/L,其次為Aspergillus niger和Agrobacterium tumefaciens;但真菌釋放鉀長(zhǎng)石中的K、Al、Si的速率最快,浸礦周期最短,綜合效率最高。分析認(rèn)為,真菌對(duì)礦物的溶蝕效果主要受有機(jī)酸酸解和絡(luò)解作用機(jī)制的影響,而硅酸鹽細(xì)菌對(duì)礦物的風(fēng)化分解能力則主要受胞外多聚物絡(luò)解作用機(jī)制的控制。
關(guān)鍵字: 真菌;硅酸鹽細(xì)菌;鉀長(zhǎng)石;溶蝕
(School of Chemistry and Environmental Engineering, Jiujiang University, Jiujiang 332005, China)
Abstract:The dynamic corrosion effects of typical silicate bacteria Paenibacillus polymyxa and Agrobacterium tumefaciens and fungus Aspergillus niger on potassium feldspar were comparative analysed by measuring the concentration of bacteria in fermentation medium, pH value, mass concentrations of K, Si and Al in leaching supernatant, and SEM and XRD analysis of potash feldspar before and after being subjected to bacterial strains. The results show that the growth period of fungus is shorter than that of silicate bacteria, and the fungus has higher acid production capacity, but silicate bacteria have longer logarithmic growth periods, higher bacterial concentrations in their culture media, and stronger abilities to produce extracellular polymers. Paenibacillus polymyxa has the best corrosion effect on feldspar, the mass concentrations of K2O, SiO2 and Al2O3 in the leaching solution are up to 2.30 g/L, 6.55 g/L and 5.20 g/L, followed by Aspergillus niger and Agrobacterium tumefaciens. However, the rates of K, Al and Si in potassium feldspar released by fungus is the fastest, its leaching period is the shortest, so the fungus has higher comprehensive leaching efficiency than the other two strains. It is concluded that the corrosion effect of fungus on minerals is mainly influenced by the mechanism of organic acidolysis and complexation, while the ability of silicate bacteria to decompose minerals is controlled by the complexation mechanism of extracellular polymers.
Key words: fungus; silicate bacterium; potassium feldspar; corrosion


