Thomas and artificial neural network models for the fixed-bed adsorption of methylene blue by a beach waste Posidonia oceanica (L.) dead leaves

► Posidonia oceanica is an important endemic sea grass in the Mediterranean Sea. ► Its dead leaves accumulated on touristic beaches are considered as beach wastes. ► This study presents an alternative evaluation method related to dead leaves of Posidonia oceanica. ► Modeling of MB biosorption by Thomas and Artificial Neural Network Models. ► These beach wastes can be used in dynamic removal of dyes from aqueous solutions. Posidonia oceanica (L.) is an endemic sea grass in the Mediterranean Sea. Its dead leaves are accumulated in the beaches. Biomass based on dead leaves of P. oceanica is considered as a beach waste. Therefore, they are burned to keep beaches clean. In the present study, an alternative eco-friendly evaluation approach for removal of methylene blue by dead leaves of P. oceanica is studied. Dynamic removal of methylene blue from aqueous solution is performed in a fixed-bed column. Effects of different flow rates and bed heights on column performance are investigated and best flow rate and bed height are observed at 7.28mL/min and 9cm, respectively. Column performance has been modeled with Thomas and Artificial Neural Network models. The results confirm that dead leaves of P. oceanica can be used as a fixed-bed material for the dynamic removal of dyes in the waste waters from textile industry.