Preparation of activated carbon rendered magnetic properties and investigation of their usage in removal of textile dye

In this study, magnetic property has been gained to the active carbon (AC) obtained from the sugar beet pulp. For this purpose, AC has been added to the medium during the magnetite synthesis obtaining from iron salts by co-precipitation metod. A number of characterization analyzes have been carried out to identify the product obtained. As a result of the X-Ray Diffration (XRD) analysis, it has been found that magnetite is integrated into the active carbon matrix (MAC). The magnetic saturation value of the MAC was found to be 11.2 emu/g by using VSM. The surface areas of MAC and AC were determined as 49.0 m2/g and 119.5 m2/g, respectively, by performing Brunauer-Emmet-Teller (BET) surface area analysis. At the result of Barrett-Joyner-Halenda (BJH) porosity analysis, AC and MAC were found to have meso (2-50 nm) porosity. Morphological analysis of AC and MAC was performed by Scanning Electron Microcope (SEM). The images taken in show that AC has a brighter and porous surface, and MAC has a porous but more matt surface. X-Ray Fluoresans (XRF) and Fourier Transform Infrared Spectroscopy (FTIR) and Energy Dispersive Spectroscopy (EDS) analyzes showed that the AC had phosphorus (P) presence in the structure of the MAC from H3PO4 activation. In addition, it was also determined that iron (Fe) from magnetite (Fe3O4) was found in the structure of MAC. In the zeta potential measurements, it was found that the isoelectric point of AC is at pH 4.10 and MAC is at pH 2.71. The removal behavior of Maxilon Blue GRL (300%) of both adsorbents from the aqueous solution was investigated under the varying conditions such as initial dye concentration, time, pH and temperature. It was observed that the dye adsorption capacities of AC and MAC increased over time with increasing dye concentration and increasing temperature. The highest dye removal value was obtained at pH 7.0 to 9.0. The highest dye adsorption capacity values obtained at room temperature using 25.0 mg/L dye solution were found to be 2.22 mg/g for AC and 2.47 mg/g for MAC. When adsorption kinetics were investigated, it was revealed that the adsorption process proceeded from the pseudo second order kinetic. In the thermodynamic evaluation, it was concluded that the adsorption occurred spontaneously and endothermic. From the adsorption isotherm evaluation made, it is understood that the adsorption phenomenon corresponds to the Freundlich adsorption isotherm.