Treatment of Amoxicillin Antibiotic from the Surface Water using Carboxymethyl Tragacanth Gum-Grafted-Polyaniline doped to Fe2O3 Bionanocomposites

Abstract

In the present study, treatment of amoxicillin (AMX) antibiotic from the surface water using carboxymethyl tragacanth gum-grafted-polyaniline doped to Fe2O3 (CMTG-g-PANI/Fe2O3) bionanocomposites (BNCs) was examined with adsorption process from pharmaceutical industry wastewater (PI ww) plant, İzmir, Turkey. Different pH values (4.0, 5.0, 7.0 and 9.0), increasing adsorption times (5 min, 10 min, 20 min and 40 min), increasing AMX concentrations (100 mg/l, 200 mg/l, 300 mg/l, 400 mg/l and 500 mg/l), increasing CMTG-g-PANI/Fe2O3 BNCs concentrations (5 mg/l, 15 mg/l, 30 mg/l and 45 mg/l), respectively, was operated during adsorption process in the efficient removals of AMX micropollutants in PI ww. The characteristics of the synthesized NPs were assessed using XRD, EDX, FESEM, FTIR, TEM and VSM analyses, respectively. Also, thermal gravimetric analysis (TGA) was operated with Brunauer–Emmet–Teller (BET) measurements by a multi-point method, and the pore parameters were calculated via the Dubinin–Astakhov (DA) method. ANOVA statistical analysis was used for all experimental samples. The maximum 99.36% AMX removal was obtained during adsorption process in PI ww at pH=7.0 and at 25oC. The maximum 99.07% AMX removal was observed during adsorption process in PI ww after 20 min, at pH=7.0 and at 25oC, respectively. The maximum 99.23% AMX removal was found with adsroption process in PI ww, at 100 mg/l AMX, after 20 min, at pH=7.0 and at 25oC, respectively. The maximum 99.20% AMX removal was measured to 5 mg/l CMTG-g-PANI/Fe2O3 BNCs with adsorption process in PI ww, at 100 mg/l AMX after 20 min, at pH=7.0 and at 25oC, respectively. The maximum 99% and 99% AMX recovery efficiencies were measured in PI ww during adsorption process, after 1. recycle time and 2. recycle time, respectively, at 100 mg/l AMX after 20 min, at pH=7.0 and at 25oC, respectively. A granular structure with good thermal stability (34wt% char yield), 8.1143 m2/g specific surface area and 23 emu/g magnetization saturation were measured for CMTG-g-PANI/Fe2O3 BNCs. 983.11 mg/g maximum adsorption capacity was observed at pH=7.0, at 20 min adsorption mixing time, at 5 mg/l CMTG-g-PANI/Fe2O3 BNCs, at 500 mg/l initial AMX concentration, respectively. The Freundlich isotherm model and the pseudo-second-order kinetic models are much more suitable with the experimental data for AMX removal in PI ww during adsorption process with CMTG-g-PANI/Fe2O3 BNCs. The adsorption/desorption process showed that CMTG-g-PANI/Fe2O3 BNCs could continue to remove AMX after three sequential adsorption/desorption cycles without significantly losing adsorption capacity. Finally, the combination of a simple, easy operation preparation process, excellent performance and cost effective, makes this CMTG-g-PANI/Fe2O3 BNCs bioadsorbent a promising option during adsorption process in PI ww treatment.