Laser induced rapid decontamination of aromatic compound from porous soil simulant

摘要

Soil contamination with organic compounds can lead to the loss of farmable and habitable lands and cause long-term human and animal exposure to toxins. This paper reports a new laser based method for in situ soil decontamination at high efficiency, in which a focused excimer laser is used to remove organic contaminants from soil through burning by generating a local high temperature region. An aromatic compound, 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene, is used as an organic contaminant, and a porous silica plate is used as a soil simulant. A heat transfer model is created to simulate the interaction between the laser and the organic compound. The lithographic mode of operation allows the accurate quantitation of laser effects. The effects of power, speed, frequency, and energy consumption on the efficiency of decontamination have been examined with high accuracy. The decomposition area increases with the increase in the laser power and the decrease in the scan speed and frequency. Given the high energy conversion yield of the high power laser, this method would be promising for large scale in situ soil decontamination.