Available silicone was melted from coal gangue samples from Hancheng dig- gings through calcination, digestion, and other means. The best calcination temperature was determined from a range of 550-1 150 ℃; and the be...Available silicone was melted from coal gangue samples from Hancheng dig- gings through calcination, digestion, and other means. The best calcination temperature was determined from a range of 550-1 150 ℃; and the best time, from a range of 0.5-5 h by colorimetry method. The proper ratio of coal gangue, limestone, sodium carbonate, and caustic soda was then determined through orthogonal experiment. The results show that the proper extraction condition for available silicone is the ratio of coal gangue, limestone, sodium carbonate, and caustic soda at 1：0.5：0.1：0.05, calcination temperature at 700 ℃, and calcination time at 2 h. In this condition, the available silicone content can be more than 19.65%.展开更多
Coal gangue was calcinated under air, nitrogen, carbon dioxide, air-hydrogen, and hydrogen atmospheres. The effects of different calcination temperatures and atmospheres on the mineral composition of activated coal ga...Coal gangue was calcinated under air, nitrogen, carbon dioxide, air-hydrogen, and hydrogen atmospheres. The effects of different calcination temperatures and atmospheres on the mineral composition of activated coal gangue were investigated by X-ray diffraction. Moreover, the acid leaching kinetics of aluminum oxide from coal gangue was investigated with sulfuric acid. It showed that the air atmosphere promoted kaolinite decomposition during coal gangue calcination. The hydrogen atmosphere promoted the activation and decomposition of kaolinite at reaction temperatures exceeding 650℃. The carbon dioxide atmosphere eliminated the influence of residual carbon on coal gangue. When the ratio of acid/coal gangue was 1.5 and reaction temperature was 650℃, the sulfuric acid leaching rate under air, air-hydrogen, carbon dioxide, hydrogen and nitrogen atmospheres were 93.66%, 90.90%, 84.06%, 81.91% and 77.54% respectively. The acid leaching reaction process conformed to unreacted shrinking core model of particle unchanged, and was controlled by the interracial chemical reaction. The reaction kinetic equation for the leaching process was 1-（1-x）1/3=kt with an apparent activation energy of 48.97 kJ/mol.展开更多
基金Supported by Education Department Project of Shannxi Province(06JK238)
文摘Available silicone was melted from coal gangue samples from Hancheng dig- gings through calcination, digestion, and other means. The best calcination temperature was determined from a range of 550-1 150 ℃; and the best time, from a range of 0.5-5 h by colorimetry method. The proper ratio of coal gangue, limestone, sodium carbonate, and caustic soda was then determined through orthogonal experiment. The results show that the proper extraction condition for available silicone is the ratio of coal gangue, limestone, sodium carbonate, and caustic soda at 1：0.5：0.1：0.05, calcination temperature at 700 ℃, and calcination time at 2 h. In this condition, the available silicone content can be more than 19.65%.
基金supported by National Natural Science Foundation of China(51074170)Shaanxi Key Technology R&D Program(2016GY-147)+1 种基金Key Laboratory of Coal Resources Exploration and Comprehensive UtilizationMinistry of Land and Resources Open Research Topic(KF2016-3)
文摘Coal gangue was calcinated under air, nitrogen, carbon dioxide, air-hydrogen, and hydrogen atmospheres. The effects of different calcination temperatures and atmospheres on the mineral composition of activated coal gangue were investigated by X-ray diffraction. Moreover, the acid leaching kinetics of aluminum oxide from coal gangue was investigated with sulfuric acid. It showed that the air atmosphere promoted kaolinite decomposition during coal gangue calcination. The hydrogen atmosphere promoted the activation and decomposition of kaolinite at reaction temperatures exceeding 650℃. The carbon dioxide atmosphere eliminated the influence of residual carbon on coal gangue. When the ratio of acid/coal gangue was 1.5 and reaction temperature was 650℃, the sulfuric acid leaching rate under air, air-hydrogen, carbon dioxide, hydrogen and nitrogen atmospheres were 93.66%, 90.90%, 84.06%, 81.91% and 77.54% respectively. The acid leaching reaction process conformed to unreacted shrinking core model of particle unchanged, and was controlled by the interracial chemical reaction. The reaction kinetic equation for the leaching process was 1-（1-x）1/3=kt with an apparent activation energy of 48.97 kJ/mol.
