Onuma Carmody

Porous materials for oil spill cleanup: A review of synthesis and absorbing properties

This paper reviews the synthesis and the absorbing properties of the wide variety of porous sorbent materials that have been studied for application in the removal of organics, particularly in the area of oil spill cleanup. The discussion is especially focused on hydrophobic silica aerogels, zeolites, organoclays and natural sorbents many of which have been demonstrated to exhibit (or show potential to exhibit) excellent oil absorption properties. The areas for further development of some of these materials are identified.

Modification of Kaolinite Surfaces through Mechanochemical Activation with Quartz: A Diffuse Reflectance Infrared Fourier Transform and Chemometrics Study

Studies of kaolinite surfaces are of industrial importance. One useful method for studying the changes in kaolinite surface properties is to apply chemometric analyses to the kaolinite surface infrared spectra. A comparison is made between the mechanochemical activation of Kiralyhegy kaolinites with significant amounts of natural quartz and the mechanochemical activation of Zettlitz kaolinite with added quartz. Diffuse reflectance infrared Fourier transform (DRIFT) spectra were analyzed using principal component analysis (PCA) and multi-criteria decision making (MCDM) methods, the preference ranking organization method for enrichment evaluations (PROMETHEE) and geometrical analysis for interactive assistance (GAIA). The clear discrimination of the Kiralyhegy spectral objects on the two PC scores plots (400–800 and 800–2030 cm−1) indicated the dominance of quartz. Importantly, no ordering of any spectral objects appeared to be related to grinding time in the PC plots of these spectral regions. Thus, neither the kaolinite nor the quartz are systematically responsive to grinding time according to the spectral criteria investigated. The third spectral region (2600–3800 cm−1, OH vibrations), showed apparent systematic ordering of the Kiralyhegy and, to a lesser extent, Zettlitz spectral objects with grinding time. This was attributed to the effect of the natural quartz on the delamination of kaolinite and the accompanying phenomena (i.e., formation of kaolinite spheres and water). The mechanochemical activation of kaolinite and quartz, through dry grinding, results in changes to the surface structure. Different grinding times were adopted to study the rate of destruction of the kaolinite and quartz structures. This relationship (i.e., grinding time) was classified using PROMETHEE and GAIA methodology.

Infrared and Raman spectoscopic study of acetylation of raw cotton for application in sorption of oil spills

Abstract: Raman and Fourier transform infrared spectroscopy (FTIR) have been used to investigate the acetylation of raw cotton in an effort to develop hydrophobic, biodegradable, sorbent materials for cleaning up oil spills. Both Raman and FTIR spectroscopy indicate successful acetylation though the Raman bands are much weaker. A linear correlation was observed between the degree of acetylation measured by Raman spectroscopy and that obtained from FTIR data.