The analysis of surface and pores of activated carbons oxidized to various degrees has been carried out on the basis of adsorption isotherms of nitrogen, water and several organic compounds. The reason for the large hysteresis of isotherms of water was ascribed to the structure formation of water in the micropores caused by the hydrophobic interaction at water-carbon inferface. INTRODUCTION The...

The aim of this study was to observe the effects of alkaline activating agents on the characteristics, composition, and surface morphology of the designed activated carbons. Activated carbons were prepared by pyrolysis of Acacia mangium wood in the presence of two basic activating agents (calcium oxide and potassium hydroxide). The extent of impregnation ratio of precursor to activating agents ...

The adsorption of Escherichia coli on different activated carbons has been studied. The activated carbon samples used have been characterized, determining their surface area, pore size distribution, elemental analysis, mineral matter analysis and pH of the point of zero charge. The adsorption capacity of these carbons increased with their hydrophobicity and macropore volume. The number of bacte...

The study of aliphatic compounds adsorption on activated carbon can be carried out from the energetic change involved in the interaction; the energy values can be determined from isotherms or by the immersion enthalpy. Vapor phase adsorption isotherms of hexane at 263 K on five activated carbons with different content of oxygenated groups and the immersion enthalpy of the activated carbons in h...

Glucose, lactose, and saccharose were used as precursors to prepare chars at 400 °C then activated at 800 °C or 1000 °C in closed vessels with controlled amounts of oxygen penetrating through nanopores in the vessel walls. There are correlations between the porosity, amounts of residual O- and H-containing functionalities, and electroconductivity of amorphous carbons studied. The pore size dist...

Sustainable porous carbons have been prepared by chemical activation of hydrothermally carbonized polysaccharides (starch and cellulose) and biomass (sawdust). These materials were investigated as sorbents for CO2 capture. The activation process was carried out under severe (KOH/precursor=4) or mild (KOH/precursor=2) activation conditions at different temperatures in the 600-800oC range. Textur...

Polypyrrole (PPy) has been prepared by oxidative polymerization of pyrrole and used as a raw material for the preparation N-doped activated carbons. Thus, PPy pyrolyzed at 900 °C then with steam under different activation conditions (time temperature). This allowed carbons porosity development nitrogen content, well distinctive distribution species. It observed that presence functionalities fav...

Different types of activated carbon were prepared by chemical activation of brewer's spent grain (BSG) lignin using H(3)PO(4) at various acid/lignin ratios (1, 2, or 3g/g) and carbonization temperatures (300, 450, or 600 degrees C), according to a 2(2) full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, an...

The storage of gases in porous adsorbents, such as activated carbon and carbon nanotubes, is examined here thermodynamically from a systems viewpoint, considering the entire adsorption-desorption cycle. The results provide concrete objective criteria to guide the search for the "Holy Grail" adsorbent, for which the adsorptive delivery is maximized. It is shown that, for ambient temperature stor...

Direct activation of biomass, via a simple and lower cost one-step process, with potassium oxalate as mild less corrosive agent, yields activated carbon properties CO 2 uptake comparable or superior to conventionally prepared carbons.