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As a continuation of our previous study, in this work, we investigated the effects of propanol and butanol treatments and subsequent irradiation with microwave on commercial vermiculites. No expansibility was observed after propanol or butanol treatments (k = 1.0). Samples treated with propanol or butanol and subsequently irradiated with microwaves expanded in a similar manner as they did with methanol and ethanol. The results of X-ray diffraction (XRD), thermogravimetric analysis (TG and DTA), scanning electron microscopy (SEM) and infrared spectroscopy indicated structural changes as: 1) The appearance of extra interstratified phases during the transformation from 2- to 1-WLHS (Water Layer Hydration States). 2) The improvement of the crystallinity and order of the most phases, which are the same phases of the untreated vermiculites or even some more, due to migration of potassium. [ABSTRACT FROM AUTHOR]

Present work reports the alcohol treatment and subsequent irradiation with microwave of commercial vermiculites. Alcohol treatment resulted in slight delamination of the layers and the color of the samples changed into brilliant golden and no expansibility was observed (k ≤ 1.3). Samples treated with alcohol and subsequently irradiated with microwaves expanded; the greater expansibility (k = 8 for 1 h) was provided by the most complex sample and treated with methanol. The structural changes were studied by using X-ray diffraction (XRD), thermogravimetric analysis (TG and DTA), infrared spectroscopy and carbon analysis. The results of these analysis indicated dehydration-hydration and order–disorder which would be related to the entry of alcohol into the vermiculites and the loss of water content. The changes occurred in a similar way to the temperature and vacuum, and were less pronounced for the purest vermiculite. The crystallite size and lattice strain values which reflect changes in crystallinity and structural order varied slightly regardless of treatment and time. Alcohol treatment and subsequent microwave irradiation may be the procedure for obtaining purest vermiculite from less pure sample. [ABSTRACT FROM AUTHOR]