Investigation On The Regeneration Of Activated Carbon By Electrochemistry

The activated carbon has been widely used in the field of environmental protection and has played an important role in the wastewater treatment especially. But it results not only the resource waste, but also the secondary pollution that the saturation activated carbon without any treatment are abandoned. Therefore, the regeneration of the saturation activated carbon is an inevitable tendency in activated carbon industry. Because the traditional techniques of regeneration of activated carbon had some shortages, including inflexible manipulation, lower regeneration efficiency and higher energy cost; the exploitation of new techniques for the regeneration of activated carbon has become an urgent problem in the field of environmental protection field. In order to explore a new technique of regeneration of activated carbon, the electrochemistry method was employed to regenerate the activated carbon which had adsorbed phenol in the laboratory scale. The experimental study can provide not only the basic data for the further study of regeneration of activated carbon by electrochemistry method, but also a new method to regeneration of activated carbon.The 10～20 meshes coaly saturation activated carbon which had absorbed simulated wastewater with phenol, then used the electrobath to regenerate the saturation activated carbon. Taking the regeneration efficiency as an assessment index, the author studied the effect of the electrolyte concentration, current density and regeneration time on the regeneration efficiency under the condition of normal temperature and atmospheric pressure (291～298K , 1.013×105Pa).The orthogonal method was employed to determine the experimental scheme. It was shown from the simulated experimental study that: (1) different kinds of electrolyte had some effect on regeneration efficiency, the regeneration efficiency increased with electrolyte concentration increased; especially when the electrolyte concentration was in the range of 0.00～1.00g/L, the regeneration efficiency increased quickly, and when the electrolyte concentration exceeded to 1.00g/L, the regeneration efficiency increased slowly. (2) The regeneration efficiency increased with the current density increased, and they had linear relation in the studied current density range. (3) The regeneration efficiency increased with the regeneration time increased, especially when the regeneration time was in the range of 0～5h, the increase rate of regeneration efficiency decreased with the regeneration time, and when the regeneration time exceeded to 5h, the increase rate of regeneration efficiency increased slowly with the regeneration time. (4) The regeneration times had some effect on regeneration efficiency; but after 4 times, the decrease of regeneration efficiency was less than 5%. (5) Under the condition of normal temperature and atmospheric pressure, the effect order of affecting the regeneration efficiency of activated carbon was the regeneration time, electrolyte concentration and current density; under the conditions of factors and levels which had been selected, it was concluded that the optimal conditions were 5h regeneration time, 2.00g/L electrolyte concentration and 3mA/cm~2 current density, the corresponding regeneration efficiency of activated carbon is 80.29%.