Experimental investigation on adsorption of odorous substances from air,Untersuchungen zur Adsorption von Geruchsstoffen aus der Luft

The removal of harmful and toxic substances in trace concentrations from gas streams is often inevitable. In this paper sorption measurements of hexanal and acetaldehyde in trace concentrations from a nitrogen gas stream on activated carbon and a newly synthesized functionalized periodic mesoporous organosilica (PMO) at 298 K and 1 bar are presented. The experimental apparatus consists of a magnetic suspension balance, which is coupled with a gas chromatograph-mass spectrometer. Thus the gravimetric measurements can be complemented by a spectrometric analysis of the sorption process. Both adsorbents show a significantly higher capacity for hexanal compared to the capacity for acetaldehyde. Furthermore, the PMO exhibits clear evidence for a chemisorption of hexanal. This can be used for selective and irreversible bonding of the adsorptives.