Journal of the Chinese Institute of Chemical Engineers, Vol.33, No.3, 243-251, 2002
Ethylene oxide removal from simulated wastewater
The sorption and removal behaviors of ethylene oxide (EO) from wastewater were investigated using the adsorption and stopping methods. Three Amberlite resins (XAD-4, XAD-7, and XAD-16) and two activated carbon fibs (CP-900 and CP1100) were employed to adsorb EO from simulated wastewater in a batch reactor. The best adsorbent was XAD-16. The unit-adsorbed ratio of EO to resin decreased with increasing amounts of resin. In the stripping method, two operating types, semibatch and continuous packed bed, were employed to remove EO. High airflow rate and high temperature were favorable for increasing the stripping efficiency. The total-tower liquid mass-transfer coefficient K-L and gas mass-transfer coefficient K-G were also obtained. In the EO recovery system, EO removal from waste gas was conducted by means of chemical absorption. The addition of an acidic agent (HCl and H2SO4) could increase the absorption efficiency in an absorption tower. The incremental concentration of the acidic agent increased the absorption efficiency. The absorbed capability of EO for both H2SO4 and HCl was high, particularly for H2SO4. The reaction-rate constant and Arrhenius activation energy were also obtained.