Volatile organic compounds (VOCs) emitted from industrial gas cause equipment failure and fire accidents due to the rapid flow and concentration changes of VOCs. Therefore, it is crucial to attenuate the concentration of VOCs to ensure a constant emission rate before the control process. This study proposed an encapsulation technique to fabricate calcium- alginate gel beads containing paraffin oil as an effective absorbent. The prepared absorbent was physically characterized, and a column test observed its absorption capacity. When the oil content was 30%, the prepared beads showed the best spherical shape, attaining 96% emulsion stability, 0.014 sphericity factor, 62.7% weight variation ratio, and 4.21 ± 0.06mm diameter. In the column test that was packed with the prepared beads, the toluene absorption capacity was 497.6mg/kg. The net effect of the beads was to attenuate the peaks of toluene concentration, and to make the VOC-laden air stream more receptive for the subsequent treatment unit.

nanopowders with anatase structure were firstly prepared by controlling the pH value of a precursor solution without any heat-treatment at room temperature. The prepared nanopowders were hydrothermally treated in 10M NaOH solution at . Then, the samples were washed in DI water or 0.1M HCl. The nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The gas sensitivity of nanotubes for toluene gas was also investigated. The results show that nanotubes can be prepared by hydrothermal treatment. The morphology of nanotubes prepared by 0.1M HCl washing is destroyed to some extent. nanotubes with DI water washing show better sensitivity than that with 0.1M HCl washing.

The deodorization performances of ammonia, acetic acid and acetaldehyde were tested for each of all forty five air cleaners sold in the online shops and department stores. The removal performances of toluene and formaldehyde were also investigated and the results were compared to the deodorization performances for the air cleaners. Filter-type and complex type air cleaners which used activated carbon filters showed superior in odor removal performances to those of ionizer type and wet type air cleaners. Toluene and formaldehyde were readily removed for the most of filter-type and complex type air cleaners. Ionizer air cleaners had little removal ability for the toluene and formaldehyde.