RESUMO
The aim of this study was to improvement of adsorption capacity of porous starch (PS) by incorporation of halloysite nanotube (HNT). PS/HNT carrier was synthesized through the solvent exchange method. Various fabrication approaches for PS were introduced and different ethanol ratio (40, 60, 80, 100%), HNT concentration (0, 0.1, 0.2, 0.3, 0.4 and 0.5â¯mg/mL) and drying method (oven, freeze dryer and microwave) were applied. The results indicated that high ratio of ethanol created larger pores and also the best results were obtained from freeze-dried samples (pâ¯<â¯0.05). Incorporation of HNT could further improve the adsorption capacity. However, the best oil and water adsorption capacity were related to PS alone. The nitrogen adsorption-desorption measurement and scanning electron microscopy elucidated the porous structure of samples. The experimental data were fitted successfully by the Langmuir model rather than Freundlich isotherm. Also PS/HNT had higher apparent density and more negative zeta potential rather than PS. However, the DSC results showed the similar thermal patterns for PS and PS/HNT.
