Adsorption and desorption of gold on the magnetic activated carbon (MAC) were investigated The adsorption rate of gold is higher than that of conventional coconut carbon in cyanide leach solution The loading gold can ...Adsorption and desorption of gold on the magnetic activated carbon (MAC) were investigated The adsorption rate of gold is higher than that of conventional coconut carbon in cyanide leach solution The loading gold can be easily desorbed as coconut carbon. Crushed fine magnetic carbon can be selected by a magnetic separator, It is suggested that the MAC can be used in carbon-in-pulp (CIP)process for increasing the recovery rate of gold展开更多
XPS(X-ray photoelectron spectroscopy) spectrometer EscA-750 was used to analyse the surface character of activated carbon, magnetic reagent and magnetic activated carbon. The distribution and change of C valence of th...XPS(X-ray photoelectron spectroscopy) spectrometer EscA-750 was used to analyse the surface character of activated carbon, magnetic reagent and magnetic activated carbon. The distribution and change of C valence of them were determined. The conclusion is that the magnetic reagent could be adsorbed on the surface of activated carbon chemically. the interpretation of adsorptive mechanism of magnetic reagent in microstructure was discussed.展开更多
Based on the special molccular structure of surfactant paramagnctic material used as magnetic nucleus wascoated with two layers of surfactant inculding an inner layer and an outer layer and an outer layer Magnetic rea...Based on the special molccular structure of surfactant paramagnctic material used as magnetic nucleus wascoated with two layers of surfactant inculding an inner layer and an outer layer and an outer layer Magnetic reagent can combine with activated carbon due to adsorption of hydrophilic raclical of the outer surfactant layer so activated carbon has magnetism Theeffects of magnetic reagent dosage. pH and activator upon the magnetic susceptibility of activated carbon were studied.Conceming the optimal conditions. MR-20 is the best magnetic reagent. Concentration of CaCl2 is 0.02M and pH1.8-2.4The physical properties of magnetic activated carbon vary with the types dosage and magnetizing condition of magneticreagent.展开更多
The source water in one forest region of the Northeast China had very high natural organic matter（NOM） concentration and heavy color during snowmelt period. The efficiency of five combined treatment processes was co...The source water in one forest region of the Northeast China had very high natural organic matter（NOM） concentration and heavy color during snowmelt period. The efficiency of five combined treatment processes was compared to address the high concentration of NOM and the mechanisms were also analyzed. Conventional treatment can hardly remove dissolved organic carbon（DOC） in the source water. KMn O4pre-oxidization could improve the DOC removal to 22.0%. Post activated carbon adsorption improved the DOC removal of conventional treatment to 28.8%. The non-sufficient NOM removal could be attributed to the dominance of large molecular weight organic matters in raw water, which cannot be adsorbed by the micropore upon activated carbon. O3＋ activated carbon treatment are another available technology for eliminating the color and UV254 in water. However, its performance of DOC removal was only 36.4%, which could not satisfy the requirement for organic matter. The limited ozone dosage is not sufficient to mineralize the high concentration of NOM. Magnetic ion-exchange resin combined with conventional treatment could remove 96.2%of color, 96.0% of UV254 and 87.1% of DOC, enabling effluents to meet the drinking water quality standard. The high removal efficiency could be explained by the negative charge on the surface of NOM which benefits the static adsorption of NOM on the anion exchange resin. The results indicated that magnetic ion-exchange resin combined with conventional treatment is the best available technology to remove high concentration of NOM.展开更多
文摘Adsorption and desorption of gold on the magnetic activated carbon (MAC) were investigated The adsorption rate of gold is higher than that of conventional coconut carbon in cyanide leach solution The loading gold can be easily desorbed as coconut carbon. Crushed fine magnetic carbon can be selected by a magnetic separator, It is suggested that the MAC can be used in carbon-in-pulp (CIP)process for increasing the recovery rate of gold
文摘XPS(X-ray photoelectron spectroscopy) spectrometer EscA-750 was used to analyse the surface character of activated carbon, magnetic reagent and magnetic activated carbon. The distribution and change of C valence of them were determined. The conclusion is that the magnetic reagent could be adsorbed on the surface of activated carbon chemically. the interpretation of adsorptive mechanism of magnetic reagent in microstructure was discussed.
文摘Based on the special molccular structure of surfactant paramagnctic material used as magnetic nucleus wascoated with two layers of surfactant inculding an inner layer and an outer layer and an outer layer Magnetic reagent can combine with activated carbon due to adsorption of hydrophilic raclical of the outer surfactant layer so activated carbon has magnetism Theeffects of magnetic reagent dosage. pH and activator upon the magnetic susceptibility of activated carbon were studied.Conceming the optimal conditions. MR-20 is the best magnetic reagent. Concentration of CaCl2 is 0.02M and pH1.8-2.4The physical properties of magnetic activated carbon vary with the types dosage and magnetizing condition of magneticreagent.
基金supported by the project of " Major Science and Technology Program for Water Pollution Control and Treatment of China " (No. 2008ZX07420-005)the Natural Science Foundation of China (No. 51290284)the Tsinghua University Initiative Scientific Research Program (No. 20131089247)
文摘The source water in one forest region of the Northeast China had very high natural organic matter（NOM） concentration and heavy color during snowmelt period. The efficiency of five combined treatment processes was compared to address the high concentration of NOM and the mechanisms were also analyzed. Conventional treatment can hardly remove dissolved organic carbon（DOC） in the source water. KMn O4pre-oxidization could improve the DOC removal to 22.0%. Post activated carbon adsorption improved the DOC removal of conventional treatment to 28.8%. The non-sufficient NOM removal could be attributed to the dominance of large molecular weight organic matters in raw water, which cannot be adsorbed by the micropore upon activated carbon. O3＋ activated carbon treatment are another available technology for eliminating the color and UV254 in water. However, its performance of DOC removal was only 36.4%, which could not satisfy the requirement for organic matter. The limited ozone dosage is not sufficient to mineralize the high concentration of NOM. Magnetic ion-exchange resin combined with conventional treatment could remove 96.2%of color, 96.0% of UV254 and 87.1% of DOC, enabling effluents to meet the drinking water quality standard. The high removal efficiency could be explained by the negative charge on the surface of NOM which benefits the static adsorption of NOM on the anion exchange resin. The results indicated that magnetic ion-exchange resin combined with conventional treatment is the best available technology to remove high concentration of NOM.
