Activated Carbon from Lignocellulosic Waste Residues: Effect of Activating Agent on Porosity Characteristics and Use as Adsorbents for Organic Species

A Review of Chemicals to Produce Activated Carbon from Agricultural Waste Biomass

“…Steam, air or their mixtures or other fluid activating agents at 800-1100 • C are also used [55]. However, excessive temperatures of, say, 1200 • C and above, lead to low carbon yields, collapse of the pore structures and ash generation [56], while devolatilising processes encourage pore formation and further enlarge any micropores created [57]. Physical activation is environmentally safe, but the speed and the temperature requirements are problematic.…”

Removal of fluoxetine from water by adsorbent materials produced from paper mill sludge

“…Chemical activation is a simple process that has been proven to increase the porosity during the pyrolysis of lignocellulosic materials [13], potassium hydroxide, sodium hydroxide and zinc chloride being among the most commonly used activating agents. Although the process of chemical activation is not quite understood, it is believed that these chemicals may act like a template for the development of microporosity [3].…”

Synthesis and Characterization of Activated Carbons Obtained from Nutshells

“…It probably correspond with -COH deformation vibrations or it could be related to the cyclic aromatic structures [20].…”

“…Moreover, all the samples exhibit two weak peaks around 2850 and 2900 cm -1 which can be attributed to C-H stretching vibrations in the methyl group [20]. The peaks around 1700-1350 cm -1 , visible for both activated carbons, are probably the result of a combination of several bands characteristic for different types of vibrations: C=O stretching vibrations in the carbonyl or lactonic groups (1650-1700 cm -1 ) [14], C=C aromatic ring stretching vibrations (∼1600 cm -1 ), -(C=C) n -bonds stretching vibrations in polienes (1590 cm -1 ), C-H stretching alkane (1350-1400 cm -1 ), and also vibrations typical for the carboxyl-carbonate structures near the wavenumber of 1400 cm -1 [20,21]. Strong and broad band for both activated carbons is observed around 1350-800 cm -1 , and it can be attributed to C-O stretching vibrations in phenolic, carboxylic or ether groups which are dominant in the HS activated carbons (higher intensity of the band).…”