微波再生载苯酚活性炭过程中再生产物分析

研究了载氮气和无载气2种条件下,微波再生载苯酚活性炭过程中再生产物的成分和苯酚随再生过程的去向分布。结果表明,无载气时,微波功率越高,再生反应器内温度越高,吸附质的高温裂解反应越彻底,再生产物以挥发性气体为主,有机质种类很少;而当微波功率较低或载氮气再生时,反应器内温度相对较低,苯酚难以被彻底分解,再生产物中含多种复杂的链状或环状有机物。此外,载氮气时,经气提、挥发而去除的苯酚量约占总吸附量的一半,再生炭上无苯酚残留,活性炭吸附性能可完全恢复乃至优化;无载气时,经挥发而去除的苯酚量只有19.9%,其余大量苯酚则在微波作用下裂解或缩合为其他物质随尾气而去除,且再生炭上仍有少量苯酚未被解吸出来。因此,前者活性炭再生的效果优于后者。

Recycled products analysis in process of regenerating activated-carbon carrying phenol using microwave

Experiments were carried out to study the component of recycled products and the distribution of phenol during the course of microwave-regeneration of activated-carbon carrying phenol under N₂ atmosphere or not.The results showed that without the carrier gas,the higher the microwave power,the higher the temperature in the reactor, and the cleavage reaction of the adsorbed substance in high temperature is complete.The main recycled products were volatile gases,and a few types of organic matter were found.While the microwave power was lower or using N₂ atmosphere as carrier gas during the regenerating activated-carbon,the temperature in the reactor was relatively low and the phenol was hard to be completely decomposed.Moreover there were many kinds of complex chain-shaped or ring-shaped organic substances.In addition,under N₂ atmosphere the phenol amount removed by stripping or volatilization was about a half of the total adsorbed amount.No phenol was found in the regenerated activated carbon.The adsorption properties of activated-carbon could be recovered thoroughly or even optimized.While without the carrier gas,the removal efficiency of phenol by volatilization was only 19.9%,and the rest of phenol was cracked or condensed to be other substances and removed with off-gases under microwave irradiation.There was a little phenol which was not desorbed on the regenerated activated carbon.Therefore,the former regeneration effect of the activated carbon was better than the latter.