Physicochemical Properties of Organophilic Clay Developed Using Hexadecyltrimethylammonium Chloride (HDTMAC) Modifier

Aims: Ogwuta clay from Unwana in the South Eastern part of Nigeria was modified by ion exchange reaction using hexadecyltrimethylammonium chloride (HDTMAC).

Study Design: This study was analyzed experimentally and instrumentally.

Place and Duration of Study: This study was carried out at the Department of Pure and Industrial Chemistry, Faculty of Science, University of Port Harcourt, Nigeria. The sample collection, literature search, experiment, results and analysis lasted for one and half years.

Methodology: Physicochemical and thermal properties of the clay were determined after modification using classical and spectroscopic techniques. A combination of the wet and dry method (X-ray Fluorescence) was used to determine the metal oxide composition. Other techniques included; Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Thermogravimetry (TG). The Cation Exchange Capacity (CEC) was determined using the methylene blue method with a value of 16.4 meq/100g after modification.

Results: The product was slightly acidic with pH 4.3. Silica (SiO2), alumina (Al2O3), Na+, and K+ were found to be 47.58 %, 18.99%, 2.27, and 0.23% respectively. The clay was limited in mineral impurities with 0.0% T4+, 0.41% Mg2+, and 0.11% Ca2+ but high in carbonaceous matter with loss on ignition (LOI) of 13.17%. A C-H asymmetric stretching was visible around the 2931.9 cm-1 region as revealed by the Fourier Transform Infra-Red analysis. The X-Ray Diffraction analysis of the modified clay showed a basal spacing of 8.121 Å. Also, the X-Ray Diffractogram revealed kaolinite as the major clay mineral with the presence of quartz and polygorskite.

Conclusion: This study posits that the modified clay can be potentially suitable for the adsorptive removal of organic contaminants in aqueous and real life media.