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Recently, several works have been done in order to study antioxidant compounds like resveratrol present in oilseeds since they are able to protect from cells damage related to heart disease and cancer. In the present research a chemical analysis and the identification of bioactive compounds of peanuts, nuts and pistachios varieties were carried out. The <strong>walnut</strong> variety showed the highest content of total phenolic compounds (1404 ± 23 mg GAE/100 g) and antioxidant capacity (191 ± 4.2 μmol TE/g). Phenolic compounds resveratrol, catechin, epicatechin and quercetin were identified in all samples.

A porous clay heterostructure (PCH) from a Mexican clay was prepared and characterized, and its aqueous phenol and dichlorophenols (DCPs) adsorption capacities were studied using a batch equilibrium technique. The PCH displayed a surface area of 305.5 m 2/g, 37.2 Å average porous diameter, and a basal space of 23.2 Å. The adsorption capacity shown by the PCH for both phenol and DCPs from water (14.5 mg/g for phenol; 48.7 mg/g for 3,4‐DCP; and 45.5 mg/g for 2,5‐DCP) suggests that the PCH has both hydrophobic and hydrophilic characteristics, as a result of the presence of silanol and siloxane groups formed during the pillaring and calcination of the PCH. The values of maximal adsorption capacity for dichlorophenols were higher than those reported for aluminum pillared clays and some inorgano‐organo clays and comparable with some ionic exchange resins.

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A mexican bentonite was used to prepare three modified clays: an organoclay (OC–CPC) by intercalating cetylpyridinium chloride (CPC), an aluminum-pillared clay (Al-PILC), and an inorganic–organic clay (IOC–CPC) prepared from Al-PILC intercalating CPC. The infrared and thermogravimetric analyses enabled us to differentiate between the structures obtained. Interlayer distance was assessed through X-ray diffraction; the OC–CPC was the clay that showed the highest value (12.4 Å). The natural clay’s specific area was 43.5 m2/g, increasing to 157.2 m2/g for Al-PILC. The OC–CPC and IOC–CPC specific areas were 13.27 m2/g and 14.5 m2/g, respectively. Al-PILC was a microporous material; whereas natural clays, OC–CPC and IOC–CPC were non-porous materials. Toluene and benzene adsorption on OC–CPC was higher than in IOC–CPC and Al-PILC. Natural clay showed no adsorption capacity for these compounds. Comparison of the GC retention times for non polar and low-polarity compounds (octyne and benzene) in columns packed with OC–CPC and a commercial non polar column (squalene) showed that the OC–CPC possessed a higher organophilic (non polar) nature than squalene. This explains the higher benzene and toluene adsorption capacity of the OC–CPC compared with the other modified clays. The toluene and benzene adsorption isotherm for OC–CPC was well-described by the GAB (Guggenheim–Anderson–De Boer) model for the whole range of relative pressure used in this work (0–0.9) describing multilayer adsorption and capillary condensation.Key words: organoclay, inorgano–organo clay, vapor phase VOC’s adsorption, clay surface properties.