Chemical Engineering Communications, Vol.204, No.8, 897-906, 2017
Extraction and Characterization of Starch from Oak Acorn, Sorghum, and Potato and Adsorption Application for Removal of Maxilon Red GRL from Wastewater
Pure starch has been isolated from different samples: oak acorn, sorghum, and potato using alkali steep and wet-milling procedure. The structure of the extracted starches was analyzed using Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction. Their physicochemical properties (water content, ash content, pH, amylose content, swelling power, and water solubility index) were determined. The FT-IR spectra of isolated native starches have shown the main bands characterizing the starch. For sorghum starch (SS) and oak acorn starch (OAS), X-ray diffractograms exhibited an A-type diffraction pattern, while potato starch (PS) displayed typical B-type pattern. Compared to sorghum and oak acorn, potato starch has shown the highest level of both swelling power and water solubility index. To estimate the color removal quality of the extracted starches, a sorption of a dye named maxilon red GRL has been carried onto them. The results of equilibrium isotherms in batch adsorption process were analyzed according to the Langmuir and Freundlich model. The characteristic parameters were determined for each model. Furthermore, the effect of initial pH and ionic strength on adsorption capacity was considered, and regeneration studies were carried out.