Effect Of Temperature And pH By Adsorption Of Methylene Blue Onto Natural Boron Ore

Abstract

In today's world, thousands of the dye stuffs are being released in the environment in the form of effluents during synthesis and dyeing processes. Colored wastewaters, which are generated from some important industries such as textile, leather, food and paper industries, is a significant problem. Methylene Blue (MB, basic blue 9, C.I. 52015; chemical formula, (C₁₆H₁₈ClN₃S·3H₂O; MW, 373.90 g mol⁻¹) was used as the adsorbate in this study. Obtained from Merck, it was used without further purification. It has a maximum visible absorbance at a wavelength of 661 nm. The effect of temperature and pH on the adsorption of methylene blue onto boron was investigated in this study. Natural boron ore was tested as an adsorbent for the removal of Methylene Blue (MB) dye from aqueous solutions at different operating conditions; initial dye concentration (100 mg/L),  and contact time (40 min time ). The influences of temperature and solution pH were examined at 25, 35 and 45 ºC and in the pH range from 2 to 12. Experiments were carried out by using 200 mL methylene blue solution. Natural boron ore was supplied in powder form and 600 mg natural boron ore was used in each experimental set.  While the solution pH was raised from 2 to 12, methylene blue removal efficiency was increased from 48,75 % to 80.04%. However, the rise in temperature caused a negligible increase in the adsorption efficiency. When, the temperature was increased from 25 to 45 ºC, the dye removal efficiency was changed from 76,94 % to 77,97 %. It was therefore determined that the solution pH has a more effective operational parameter than temperature.