Studies On Bioleaching Of Manganese From Electrolytic Manganese Residue With Dominant Strains

Microbial metallurgy is an economical method for the recovery of metals from minerals, especially from low grade ores, overburden and waste from current mining operations, which requires moderate capital investment with low operating cost. Furthermore, Microbial metallurgy is generally more environmentally friendly than conventional metal recovery processes. Therefore, it is of great significance for screening efficient strains and studying the mechanisms of bioleaching. CaoJianBing etc have extract a plant from electrolytic manganese residue soil and water,which has strong Mn-resistance named fungi A5, and analysed the microorganism preliminarily. In the microbial metallurgy, the research of microorganism breeding and leaching mechanism are of great significance. In this study, through the amplification26S rDNA D1/D2area sequence, the microorganism was further identified as one of the kind of Fusarium genera. In order to study the bioleaching of manganese from electrolytic manganese role and its boileaching rates, the mechanism of electrolytic manganese residue with Fusarium sp. Characteristics as the starting point, through the wave bottle experimental examines pulp density, inoculation quantity, time initial pH and results of manganese metal ions factors effecting the efficiency of results, so as to obtain the optimal conditions of boileaching of manganese and investigates Fusarium sp. And results before and after manganese residue characterizing the morphological changes, and its leaching manganese ability was studied, and discusses the baptism of Fusarium sp. Manganese mechanism.From electrolytic manganese residue soil screen separation to a plant resistance strong manganese mould named A5, its shape characteristic is studied already. Its hyphae slender, colonies loose, the surface has green, blue bacterial colonies, black, orange different color, medium on both sides of the color has certain differences. Based on26S rDNA, sequencing result indicates that this bacterium belongs to a kind of Fusarium genera. Using Fusarium sp. Conduct manganese residue wave bottle leaching, the experimental results show that pulp density to10%(m/v), microbial inoculated quantity2%(v/v), time for36results around, environment temperature for28℃, wave bottle oscillation rate for120rpm conditions, Mangenese leaching rate is highest, when pulp density continue to increase, manganese leaching rate will declines, Manganese leaching rate increased with the over time, when36h maximum; Microbial inoculation quantity and changes of manganese leaching rate little impact. Fe2+and Fe3+join can effectively improve manganese leaching rate, but if the solution exists poisonous and harmful metal ions, such as Hg2+, manganese the leaching efficiency would greatly reduce.Using liquid chromatography and meteorological chromatographic means as the determination of manganese manganese residue microbial results in the process of organic results in solution, varieties and contents, in part yield higher organic acids were qualitatively and quantitatively determined,6kinds of organic types and relative proportions were confirmed. Through the mycelium dry weight method for the determination of microbial different growth periods of biomass change trend, painted microbial growth curve, combined with different periods of microbial produce organic acid, can discover, microbial organic produce as growth situation, is closely related. Organic growth in logarithmic quantity also increased dramatically, thus solution concentration of organic acid will increases rapidly, Arrive smoothly period, organic production peak, this time, the organic acid yield maintain a balance of production and state, that is, organic production rate and consumption rate reaches equilibrium, performance for organic acid concentration remain stable. At the same time use electron scanning techniques, studies the manganese residue particles characterization at the results before and after shape variation characteristics. Manganese The results showed that results before and after, manganese residue particles have significant changes characterized. Results the manganese residue before, the surface is tiny granule, mutually combine comparative density. But, after the tiny results granular surface material significantly reduced, instead of internal larger diameter of manganese residue group, the emergence of the floe surrounded with physical existence, it was obviously filamentous mould of microbial Fusarium sp., may be Fusarium sp. Absorption function and their metabolic produce organic dissolved surface of tiny granule manganese residue. Visible, microbial activity of manganese residue has certain stimulative effect.According to adscititious independent organic acid manganese investigated for the bioleaching ability. Investigated propionic acid, citric acid, oxalic acid, as well as several big producers, coverage is more of organic acid manganese manganese residue results alone when the results, the results show that the efficiency of different concentrations of propionic acid, citric acid, and the manganese manganese residue of oxalic acid to have certain results ability. Waiting for the same amount of organic acid and Moore leaching time conditions, citric acid manganese residue results relatively strong capacity and increased with the increase of the concentration, the efficiency is manganese results higher. Results15days plus quantity is0.5M citric acid leaching rate of manganese reach55%. Manganese the leaching efficiency as time increases gradually raised,15days basic remained stable. Visible, organic acid manganese results to have certain ability, but because the results cycle is too long, unfavorable to practical application. In addition, but also through such as blank control experiment investigation deionized water, culture medium for these factors such as the influence of manganese results, the results show that the results of manganese deionized water, and basically no influence on medium can be leaching part manganese ion, mainly because the medium Fe2+and joined the Fe3+etc metal ions, because these metal ions in mn results in the process to have very important role, such as Fe2+was good results manganese reductant, and thus be able to achieve high efficiency results. Meanwhile to Fusarium sp. The results before and after the scanning electron microscopy (sem), the result show that Fusarium sp. Metabolic processes produce biological acid and part of the reaction, Fusarium sp. Itself in manganese leaching process also have certain adsorption effect.