Determination of adsorption entropies on solid surfaces by reversed-flow gas chromatography.
The reversed-flow gas chromatography (RF-GC) method has been applied to measure the time separation of adsorption entropies and their probability density functions, when acetic and formic acid vapors, responsible for artifacts degradation inside museums, are adsorbed on various heterogeneous surfaces. The solid materials studied were Penteli marble and solid metals (lead, copper and iron), which are commonly used for the construction of the artifacts. Physicochemical measurements were performed at various temperatures in the range 353-473 K, the surface coverage theta being also calculated over time. A new mathematical model, based on well known equations was used in order to extract the above quantities.
Dremetsika
A V
AV
Environmental Analysis Group, Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Panepistimioupoli, 15771 Zografos, Athens, Greece. dremetsika@chem.uoa.gr
Siskos
P A
PA
Katsanos
N A
NA
D000327:Adsorption; D002627:Chemistry, Physical / Q000379:methods*; D002849:Chromatography, Gas / Q000379:methods*; D003300:Copper / Q000032:analysis; D019277:Entropy; D004867:Equipment Design; D007501:Iron / Q000032:analysis; D007700:Kinetics; D007854:Lead / Q000032:analysis; D015233:Models, Statistical; D008962:Models, Theoretical; D013499:Surface Properties; D013696:Temperature; D013816:Thermodynamics; D013997:Time Factors
D007854:Lead; D003300:Copper; D007501:Iron