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Six types of activated carbons were prepared from coffee residues by varying activating agents of zinc chloride, nitrogen, carbon dioxide and steam. Characterization of these samples was performed by using nitrogen adsorption isotherms, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) in order to understand the coffee residue activated carbon and its adsorptive capacity. All of activated carbons and one commercial activated carbon (CH-I1000) were subjected to the adsorption of formaldehyde vapor. The coffee activated carbon prepared with ZnCl2 impregnation and nitrogen activation (CZn一N2) demonstrates its highest capacity of formaldehyde adsorption owing to the hydrophilic functional groups of O一H, C＝O, C一O on the surface. The coffee activated carbon prepared with ZnCl2 impregnation coupled with carbon dioxide activation (CZn一N2一CO2) yields the highest total surface area (914 ± 21 m2/g) and total pore volume (1.010 ± 0.003 cc/g) with the hydrophobic groups on the surface adsorbed formaldehyde less than CZn一N2. Therefore, we conclude that the formaldehyde adsorption by activated carbons in this work is affected by surface chemistry more than texture characteristics of surface area and pore volume. [Copyright &y& Elsevier]

Abstract: A new strategy for single-step synthesis of copper and carbon nanoparticle composite by arc discharge in liquid nitrogen was proposed. The synthesized products consist of carbon nanoparticles (CNPs) which include multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanohorns (SWCNHs) and multi-shelled carbon nanocapsules (MSCNCs) containing Cu clusters inside. Evidence of transmission electron microscopic analyses reveal that under with arc current of 180A arc discharge between copper and graphite electrodes in liquid nitrogen could provide MSCNCs with narrow size distribution in a range of 70–150nm. Meanwhile, MWCNTs with diameter of 20–40nm and length of 150–350nm became selectively synthesized under the condition of discharge in liquid nitrogen with arc current of 100A. Spectroscopic analyses confirm that copper nanoparticles are cuprite while BET analyses also reveal that the synthesized nanocomposite possess acceptably high specific surface area. [Copyright &y& Elsevier]

Abstract: In this work, ultrasonic irradiation (with suitable reactant ratios) during gelation of RF solution is a promising technique for maintaining porous properties of carbon gels prepared by microwave drying. [Copyright &y& Elsevier]

Abstract: Mesoporous silica materials were synthesized by sol–gel method using tetraethoxysilane (TEOS) as precursors and surfactants i.e., cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and polyoxyethylene cetyl ether (Brij 56) as templates. Surfactant templates were completely removed by calcination to form mesoporous structure. The effects of type and amount of surfactants on the characteristics of samples were studied. The textural characteristics such as surface area, pore volume, pore size, and pore size distribution were determined by nitrogen sorption isotherms. Fourier transform infrared (FTIR) spectroscopy was employed to qualitatively identify the chemical functionality and to confirm the removal of surfactant template. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to directly observe surface morphology and mesoporous structure, respectively. The adsorption capacity of the synthesized adsorbent for toluene vapor was examined. We found that the pore volume and pore size of mesoporous materials affected the adsorption capacity. The sample prepared with high content of CTAB under basic condition (pH ) yielded large pore volumes and pore sizes and subsequently possessed the high adsorption capacity for toluene vapor. [Copyright &y& Elsevier]

Abstract: A new method in preparation of 3D interconnected macroporous carbon monolith has been introduced. Ultrasonic irradiation (ultrasonic intensity 78W/cm2) and low catalyst concentration (C/W=10mol/m3) of RF solution are used as an interesting and unique preparation method for 3D interconnected macroporous sonogel (gel irradiated by ultrasound at gelation stage) and/or 3D interconnected macroporous carbon monolith without using templates. [Copyright &y& Elsevier]

Activated carbons were produced from several solid wastes, namely, waste PET, waste tires, refuse derived fuel and wastes generated during lactic acid fermentation from garbage. Activated carbons having various pore size distributions were obtained by the conventional steam-activation method and via the pre-treatment method (i.e., mixture of raw materials with a metal salt, carbonization and acid treatment prior to steam-activation) that was proposed by the authors. The liquid-phase adsorption characteristics of organic compounds from aqueous solution on the activated carbons were determined to confirm the applicability of these carbons, where phenol and a reactive dye, Black5, were employed as representative adsorbates. The hydrophobic surface of the carbons prepared was also confirmed by water vapor adsorption. The characteristics of a typical commercial activated carbon were also measured and compared. It was found that the activated carbons with plentiful mesopores prepared from PET and waste tires had quite high adsorption capacity for large molecules. Therefore they are useful for wastewater treatment, especially, for removal of bulky adsorbates. [Copyright &y& Elsevier]