Instrumental Characterization of Unmodified and HDTMA-Br Modified Kaolinite Clay: SEM-EDX, Quantachrome and TGA-DTA

Abstract

Kaolinite clay from Alkaleri Northeast Nigeria was pre-treated and beneficiated using physical process The treated clay of cation exchange capacity (CEC) 95 meq/100 g was modified with cationic surfactant hexadecyltrimethylammonium bromide (HDTMA-Br) with amount equivalent to and doubled the CEC The unmodified kaolinite clay (UKC) and the resultant organo-kaolinite clays: monolayer modified clay (MMC) and bilayer modified clay (BMC) were characterized using the following instruments: Energy Dispersive X-ray spectrometer (EDX), Scanning Electron Microscopy (SEM), Quantachrome and Thermogravimetric-Differential Thermal Analysis (TG-DTA) EDX profile analysis shows 2241 % C, 5617 % O & 1056 % Al in UKC; 2106 % C, 5549 % O & 1166 % Al in MMC and 1898 % C, 5459 % O & 1214 % Al in BMC respectively; with Fe and K found in MMC The SEM morphology shows UKC has high porosity and large particles, while MMC and BMC showed fine particles and darker than UKC with textural non-uniformity TGA curve shows that UKC attains equilibrium decomposition at 99720 o C with 1532 % weight loss, MMC 99730 o C with 3267 % weight loss and BMC 99890 o C with 3723 % weight loss The revealed weight loss indicates water of hydration and dehydroxylation The DTA curves show endothermic at 510 o C, 250 o C and 520 o C for UKC, MMC and BMC respectively The single point surface area was 119754 m 2 /g, 30132 m 2 /g and 38225 m 2 /g for UKC, MMC and BMC with corresponding adsorption average pore width 3550050 A, 4786275 A and 7528364 A respectively Clay materials being promising minerals when modified can achieve desired surface properties for best performance in adsorption applications