Bacterial adhesion is crucial to the dissolution of minerals and rocks. By employing dialysis method, we designed comparative experiments to investigate the dissolution behavior of anorthite with the mediation of both...Bacterial adhesion is crucial to the dissolution of minerals and rocks. By employing dialysis method, we designed comparative experiments to investigate the dissolution behavior of anorthite with the mediation of both adhered and non-adhered Paenibacillus polymyxa. The results show that during 10 experimental days, the dissolution of anorthite was promoted considerably by P. polymyxa and metabolites. Nanoscale precipitates were formed in contact experiment. Anorthite has a higher release of Ca and lower releases of Al and Si in dialysis experiment than in contact experiment. The difference implies that the release of Ca is controlled by mechanism of proton-exchange, whereas those of A1 and Si are controlled by ligand-complexation in which A1-O-Si bonds are destroyed first. Kinetically the release of Ca is controlled mainly by surface reaction and leached-layer diffusion. Both of them are restrained by adhered bacteria. The releases of AI and Si are controlled mainly by surface reaction, which is accelerated by adhered bacteria.展开更多
基金supported by National Basic Research Program of China (Grant No. 2007CB815603)National Natural Science Foundation of China (Grant No. 40802015)Ph. D. Programs Foundation of Ministry of Education of China (Grant Nos. 20050284043,20050284044)
文摘Bacterial adhesion is crucial to the dissolution of minerals and rocks. By employing dialysis method, we designed comparative experiments to investigate the dissolution behavior of anorthite with the mediation of both adhered and non-adhered Paenibacillus polymyxa. The results show that during 10 experimental days, the dissolution of anorthite was promoted considerably by P. polymyxa and metabolites. Nanoscale precipitates were formed in contact experiment. Anorthite has a higher release of Ca and lower releases of Al and Si in dialysis experiment than in contact experiment. The difference implies that the release of Ca is controlled by mechanism of proton-exchange, whereas those of A1 and Si are controlled by ligand-complexation in which A1-O-Si bonds are destroyed first. Kinetically the release of Ca is controlled mainly by surface reaction and leached-layer diffusion. Both of them are restrained by adhered bacteria. The releases of AI and Si are controlled mainly by surface reaction, which is accelerated by adhered bacteria.
