SORPTION AND DESORPTION OF LINDANE BY WOOD CHARCOAL IN FIXED-BED REACTOR

Sorption and desorption of lindane (gamma-HCH) by wood charcoal (WC) a nd wood charcoal treated by 1N HNO3 (WCT) in fixed-bed reactor (FBR) w ere investigated in this study. WCT revealed a better performance than WC, in removing lindane in FBR. The breakthrough of lindane was signi ficantly affected by the size of WCT, flow rate to the FBR, and depth of WCT bed. The removal of lindane in the presence of mixture of other pesticides was considerably reduced. The design parameters for FBR we re calculated based an the bed-depth service time (BDST) approach. Man y parameters Viz. depth of sorption zone, velocity of sorption, sorben t use rate, critical bed-depth, bed efficiency, and service time, were determined for design of the fixed-bed. Using the material balance pr inciple, the characteristics of the wave-front were evaluated and foun d that the wave-front velocity is approximately equal to the sorption velocity determined from the BDST approach. Desorption studies were pe rformed in dilute organic solvent media and they gave an excellent per formance in regeneration process.