Results
The relationship between surface chemistry and sorption performance was studied on ash-free polymer-based carbons. In carbons that were morphologically similar and contained oxygen, nitrogen and hydrogen hetero atoms, the role of the surface chemistry was demonstrated in sorption processes from both the vapour and the liquid phase. The surface properties influence not only the adsorption equilibrium but play a role in the kinetics as well. A new function was introduced to follow the pore filling. Its applicability was shown for polar and nonpolar vapours. The possibility of introducing further, mainly metal, heteroatoms was studied at various stages of the carbon synthesis. In the case of lignocellulosic matrices we found that introducing Si and Na atoms (in the form of waterglass) results in improvement of mechanical strength rather than of the adsorption properties. When metal ions were added to the polymer precursor during the polymerization step or before the drying process, both the morphology and the porosity of the matrix can be severely influenced. Post-carbonization treatment, however, leads to obstruction of the pore entrance and thus a reduction of the accessible porosity.
http://real.mtak.hu/1479/