Adsorptive conversion of nitrogen dioxide from etching vent gases over activated carbon

Abstract

Some metal etching operations emit waste gases with reddish-brown (yellow when diluted) NO fume which may cause visual and acidic-odor complaints, as well as negative health effects. This study provides a simple process for the adsorptive conversion of NO in caustic-treated waste gases vented from metal-etching operations through a GAC column. With an EBRT of 0.20 sec, a conversion capacity of 0.80 kg NO (kg GAC) with an influent NO of 40 ppm can be used as a basis for system design. Saturated GAC can be regenerated at least twice by simply scrubbing it with aqueous caustic solution.

Which Is More Environmentally Friendly? A Comparative Analysis of the Environmental Benefits of Two Waste-to-Energy Technologies for Plastics Based on an LCA Model

“…However, it will have a negative impact on freshwater eutrophication and freshwater ecotoxicity. The acid gas detergent currently used in incineration power generation technology is quicklime, which generates further environmental pollution; activated carbon also exhibits a similar acidic waste gas scrubbing capacity to lime [51,52]. Changing the acid gas detergent to a composite structure of activated carbon + limestone could be considered, as could increasing the proportion of activated carbon used.…”