Papers by Keyword: Porous-Clay

Abstract: A wide variety of toxic metals and organic chemicals are discharged to the environment as industrial or laboratory wastes, causing serious water, air, and soil pollution. One of the interesting materials for using as the adsorbents to adsorb these pollutants in wastewater treatment is porous clay heterostructures (PCHs). These porous materials are obtained by the surfactant-directed assembly of mesostructured silica within clay layers. In the present work, the PCHs were synthesized within the galleries of Na-bentonite clay by the polymerization of tetraethoxysilane (TEOS) in surfactant templates (cetyltrimethylammonium ion and dodecylamine). These PCHs were functionalized with 3-mercaptopropyltrimethoxysilane (MPTMS) to obtain the MP-PCH utilizing as heavy metal adsorbent. According to N2 adsorption-desorption data, the results show that PCH has surface areas of 549.7 m2/g, an average pore diameter in the supermicropore to small mesopore range of 3.16 nm, and a pore volume of 0.45 cc/g, while MP-PCH shows pore parameters of 488.7 m2/g, 3.28 nm, and 0.48 cc/g, respectively. Moreover, the MP-PCH was investigated the adsorption properties which concerned with their function as adsorbents for aqueous solution. The results show that the adsorption capacity of MP-PCH was 0.22, 0.24, 0.50 , 0.48 and 0.11 mmol/g for Cd, Cu, Mn, Ni and Pb, respectively. They point out the potential for utilizing as the heavy metal adsorbents in wastewater treatment.

Abstract: A new porous benzene-silica hybrid clay heterostructure has been prepared by a template-assisted method. The synthesis of Hybrid Porous Clay Heterostructures (HPCH) has been performed via the intercalation of a quaternary ammonium cation surfactant (cetyltrimethylammonium bromide) and a neutral amine (octylamine) as cosurfactant, in a Portuguese clay, to direct the interlamellar hydrolysis and condensation polymerisation of neutral inorganic etraethylorthosilicate (TEOS) together with an organic precursor, the 1,4- bis(triethoxysilyl)benzene (BTEB). The material has been characterised by elemental analysis, powder X-ray diffraction, nitrogen adsorption, 13C CP MAS, 29Si MAS and CP MAS NMR spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermal analyses. The hydrophobicity of the material was tested by water adsorption. Its potential application as adsorbent of volatile organic compounds was studied by the adsorption of methanol, methyl ethyl ketone, toluene and trichloroethylene.