The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the e...The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.展开更多
采用软锰矿为氧化剂,在酸性条件下对糖蜜酒精废液进行氧化脱色降解,并同时浸出Mn。考察了反应温度、H2SO4浓度、软锰矿质量浓度等因素对糖蜜酒精废液脱色率、COD去除率和软锰矿中Mn浸出率的影响,并对反应过程机理进行了初步的探讨。结...采用软锰矿为氧化剂,在酸性条件下对糖蜜酒精废液进行氧化脱色降解,并同时浸出Mn。考察了反应温度、H2SO4浓度、软锰矿质量浓度等因素对糖蜜酒精废液脱色率、COD去除率和软锰矿中Mn浸出率的影响,并对反应过程机理进行了初步的探讨。结果表明,在Mn浸出量较小的情况下,即可获得较高的脱色率,而COD去除率却随Mn浸出量的增大而提高。在反应后期,部分有机物只能被氧化为有机酸,而不能进一步氧化为CO2。在反应温度90℃,H2SO4浓度1.1 mol/L,软锰矿质量浓度100 g/L,反应时间120 m in及采取二段反应工艺时,糖蜜酒精废液的脱色率可达98.2%,COD去除率达78.5%,软锰矿中Mn浸出率达到92.3%。展开更多
基金Supported by the National Natural Science Foundation of China （20866001） the Natural Science Foundation of GuangxiProvince （0832035）
文摘The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.
文摘采用软锰矿为氧化剂,在酸性条件下对糖蜜酒精废液进行氧化脱色降解,并同时浸出Mn。考察了反应温度、H2SO4浓度、软锰矿质量浓度等因素对糖蜜酒精废液脱色率、COD去除率和软锰矿中Mn浸出率的影响,并对反应过程机理进行了初步的探讨。结果表明,在Mn浸出量较小的情况下,即可获得较高的脱色率,而COD去除率却随Mn浸出量的增大而提高。在反应后期,部分有机物只能被氧化为有机酸,而不能进一步氧化为CO2。在反应温度90℃,H2SO4浓度1.1 mol/L,软锰矿质量浓度100 g/L,反应时间120 m in及采取二段反应工艺时,糖蜜酒精废液的脱色率可达98.2%,COD去除率达78.5%,软锰矿中Mn浸出率达到92.3%。
