Application of raw peach shell particles for removal of methylene blue

A possibility to apply raw, powdered peach shells ( PS) as a biosorbent for water purification was studied. The PSs are locally available as a solid waste in a fruit juice factory; methylene blue (MB) was chosen as representative of common pollutants in textile industry wastewater. The phase composition of prepared particles was identified by XRD. The particle morphology was characterized by FE-SEM, while the size distribution was measured by a laser light-scattering particle size analyzer. The BET specific surface area was determined from N-2 adsorption/desorption experiments. The effect of operating parameters: the biosorbent amount (50-1000 mg/100 mL), contact time (10-180 min), solution pH (2-12) and initial concentration (10-100 ppm) on biosorption efficiency was examined. Optimal conditions for MB removal were found to be: the biosorbent amount of 400 mg/100 mL and pH 5.5. A high efficiency of MB removal was established after 180 min: 99% for [MB](i) = 10 ppm and 76% for [MB](i) = 100 ppm. Biosorption is well described by the Freundlich- and BET-type isotherms, implicating heterogeneous adsorption sites and interconnections between adsorbed molecules. The FTIR spectroscopy results indicate hydrogen bonding between the dye and the biomass. The obtained results shown that raw peach shell particles could be used as an efficient low-cost biosorbent for dye removal from water. (C) 2015 Elsevier Ltd. All rights reserved.