Adsorption of chlorinated volatile organic compounds using activated carbon made from Jatropha curcas seeds

• Jatropha seeds were used to produce the activated carbon.
• Various chlorinated VOCs were measured adsorption isotherms by gravimetric method.
• Isotherms of adsorption by activated carbon (from Jatropha seed) were discussed.
• Relationship between chlorine atoms in CVOCs and sorbent capability were discussed.
• Reliability and regeneration tests showed the stability and reusability of ACJS.

In the present study, Jatropha curcas seeds (JS) were used as the raw material for the production of activated carbon by simple thermo-chemical activation with NaOH as a chemical activating agent. Various chlorinated volatile organic compounds (carbon tetrachloride, chloroform, dichloromethane, tetrachloroethylene, trichloroethylene, and chlorobenzene) were tested for the single-component adsorption study using the gravimetric adsorption method. The study focused on the adsorption of chlorinated volatile organic compounds, and the effect of the number of chlorine atoms in the molecule to the adsorption uptake. Results from the experiments showed that adsorption by activated carbon increased with increasing number of chlorine atoms and hence, with increasing molecular weight. There is, however, no significant difference between the adsorption of molecules with the same number of chlorine atoms but with different bond orders. It indicates that the influence of molecular weight is more important than the existence of double bonds within the molecule. The reusability of the activated carbon was proved when no significant decrease in its adsorption capacity was observed even after the fourth time of regeneration.