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Wood is considered a versatile and valuable material. It is used as an energy source or as a structural material -for its mechanical properties and visual appearance- and also for the production of non-food consumer products, such as pharmaceutical products, adhesives, textile products, polymeric compounds, cosmetics, papers and various basic products. Motivated by the diversity of wood species and the increasing availability of wood residues, the following investigation is intended to characterize the residues of three timber species that predominate in Colombian industry: Tectona grandis, Pinus patula and Acacia mangium, in order to promote their transformation into industrial products of greater value than the waste product. Sample wood was subjected to physical, chemical and thermal characterization by means of tests of: density, pH, last analysis, proximal analysis, lignocellulosic content, extractive and calorific value. The results obtained allowed the evaluation of wood waste as a resource of greater value to generate recycled products such as particle boards, fibers or laminated and other materials such as biopulps, composite materials, bioadsorbents and activated carbon, and also the production of fuels type biochar, syngas and bio-oil. [ABSTRACT FROM AUTHOR]

Activated carbons (AC) are microporous materials that have high adsorptive capacity. The heterogeneity of any adsorbent, in particular of the AC, can be separated into two large families: energetic and structural. Structural heterogeneity is caused by the presence of pores of different sizes, shapes and how they are interconnected, while the energy heterogeneity is caused by surface irregularities, as well as by the presence of functional groups and / or impurities. In this paper we discuss different models of surface heterogeneity in materials with slit pores and its effect on adsorption isotherms and the pore size distributions (PSD). [ABSTRACT FROM AUTHOR]

Benzothiazoles, such as benzothiazole (BT), 2-hydroxybenzothiazole (OHBT), and 2-methylbenzothiazole (MeBT) are toxic and poorly biodegradable organic compounds, frequently present in wastewater from rubber related applications. Activated carbon adsorption has been identified as an attractive treatment to removing those contaminants. This paper presents experimental results on the effect of chemical surface properties of activated carbon on the adsorption mechanism of benzothiazoles. Activated carbons with different surface chemical composition were prepared from a Filtrasorb-400 activated carbon. Pre-treatment of activated carbon included de-oxygenation and ozonation with different ozone doses. Experimental results showed that high surface concentration of oxygenated electron withdrawing groups produced a significant reduction on carbon adsorption capacity of benzothiazoles. The results suggest that adsorption mechanism of benzothiazoles would mainly take place by π-π dispersion interactions between the π-electrons of aromatic ring of benzothiazole molecules and the π-electrons of carbon graphene layers. When pH was higher than point of zero charge (pHPZC) of the activated carbon, repulsive electrostatic interactions appeared between adsorbate and ionised oxygenated surface groups, lowering the carbon adsorption capacity of benzothiazoles. [ABSTRACT FROM AUTHOR]

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