Proper utilization of the FeSO4·7H2O waste slag generated from TiO2 industry is an urgent need, and Fe3O4 particles are currently being widely used in the wastewater flocculation field. In this work, magnetite wa...Proper utilization of the FeSO4·7H2O waste slag generated from TiO2 industry is an urgent need, and Fe3O4 particles are currently being widely used in the wastewater flocculation field. In this work, magnetite was recovered from ferrous sulphate by a novel co-precipitation method with calcium hydroxide as the precipitant. Under optimum conditions, the obtained spherical magnetite particles are well crystallized with a Fe304 purity of 88.78%, but apt to aggregate with a median particle size of 1.83 μm. Magnetic measurement reveals the obtained Fe304 particles are soft magnetic with a saturation magnetization of 81.73 A-m2/kg. In addition, a highly crystallized gypsum co-product is obtained in blocky or irregular shape. Predictably, this study would provide additional opportunities for future application of low-cost Fe3O4 particles in water treatment field.展开更多
A novel wet-chemical method for the preparation of silver flakes was studied. The well-defined particles were prepared by directly adding FeSO4 solution into AgNO3 solution containing citric acid at an agitation speed...A novel wet-chemical method for the preparation of silver flakes was studied. The well-defined particles were prepared by directly adding FeSO4 solution into AgNO3 solution containing citric acid at an agitation speed of 150 r/min at room temperature. The products were characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that particles are irregular thin silver flakes. And the sizes of them range from 2 to 10 μm. It is found that citric acid plays an important role in the formation of sliver flakes. There is an optimum amount of citric acid for the preparation of silver flakes by this method. It is also found that high reduction rate is favorable for the formation of silver flakes.展开更多
为考察较低温度(<17℃)条件下添加微量金属元素对厌氧发酵产气量的影响,在发酵底物TS(含固率)为10%下采用10 L玻璃瓶作反应器,以牛粪为原料,向厌氧生物反应器中分别添加MnSO4、FeSO4·7H2O、电解锰渣,分析了厌氧消化系统运行过...为考察较低温度(<17℃)条件下添加微量金属元素对厌氧发酵产气量的影响,在发酵底物TS(含固率)为10%下采用10 L玻璃瓶作反应器,以牛粪为原料,向厌氧生物反应器中分别添加MnSO4、FeSO4·7H2O、电解锰渣,分析了厌氧消化系统运行过程中的产气量、COD(化学需氧量)和pH的变化。结果表明,锰元素能促进低温下牛粪的厌氧发酵,加速反应启动。当添加6 g MnSO4、100 g电解锰渣时,单位质量VS产气率分别为0.26 mL/g和0.64 mL/g,添加6 g FeSO4·7H2O与空白对照组均未见明显产气。展开更多
基金Project(2013A090100013)supported by the Special Project on the Integration of Industry,Education and Research of Guangdong Province,ChinaProject(201407300993)supported by the High-Tech Research and Development Program of Xinjiang Uygur Autonomous Region,China
文摘Proper utilization of the FeSO4·7H2O waste slag generated from TiO2 industry is an urgent need, and Fe3O4 particles are currently being widely used in the wastewater flocculation field. In this work, magnetite was recovered from ferrous sulphate by a novel co-precipitation method with calcium hydroxide as the precipitant. Under optimum conditions, the obtained spherical magnetite particles are well crystallized with a Fe304 purity of 88.78%, but apt to aggregate with a median particle size of 1.83 μm. Magnetic measurement reveals the obtained Fe304 particles are soft magnetic with a saturation magnetization of 81.73 A-m2/kg. In addition, a highly crystallized gypsum co-product is obtained in blocky or irregular shape. Predictably, this study would provide additional opportunities for future application of low-cost Fe3O4 particles in water treatment field.
基金Project(B20121806)supported by the Science and Technology Research Program of Education Department of Hubei Province,China
文摘A novel wet-chemical method for the preparation of silver flakes was studied. The well-defined particles were prepared by directly adding FeSO4 solution into AgNO3 solution containing citric acid at an agitation speed of 150 r/min at room temperature. The products were characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that particles are irregular thin silver flakes. And the sizes of them range from 2 to 10 μm. It is found that citric acid plays an important role in the formation of sliver flakes. There is an optimum amount of citric acid for the preparation of silver flakes by this method. It is also found that high reduction rate is favorable for the formation of silver flakes.
文摘为考察较低温度(<17℃)条件下添加微量金属元素对厌氧发酵产气量的影响,在发酵底物TS(含固率)为10%下采用10 L玻璃瓶作反应器,以牛粪为原料,向厌氧生物反应器中分别添加MnSO4、FeSO4·7H2O、电解锰渣,分析了厌氧消化系统运行过程中的产气量、COD(化学需氧量)和pH的变化。结果表明,锰元素能促进低温下牛粪的厌氧发酵,加速反应启动。当添加6 g MnSO4、100 g电解锰渣时,单位质量VS产气率分别为0.26 mL/g和0.64 mL/g,添加6 g FeSO4·7H2O与空白对照组均未见明显产气。
