Nb2O5 monolith as an efficient and reusable catalyst for textile wastewater treatment
Franco David Troncoso, Gabriela Marta Tonetto
Abstract
Abstract In this work, the degradation of methylene blue (MB) in aqueous solution by a heterogeneous Fenton-like process was studied. Nb 2 O 5 supported on an anodized aluminum monolith was used as catalyst. The Nb 2 O 5 coating generated during the catalyst synthesis was uniform and porous, with a thickness of 7 μm. Response surface methodology was used to study the relationship between process variables and MB degradation and chemical oxygen demand (COD) reduction. The optimal operating conditions were: initial MB concentration of 45 mg L − 1 , initial H 2 O 2 concentration in the reaction medium of 40 mM, catalyst loading of 7.85 $$ {\mathrm{kg}}_{{\mathrm{Nb}}_2{\mathrm{O}}_5} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>kg</mml:mi> <mml:mrow> <mml:msub> <mml:mi>Nb</mml:mi> <mml:mn>2</mml:mn> </mml:msub> <mml:msub> <mml:mi>O</mml:mi> <mml:mn>5</mml:mn> </mml:msub> </mml:mrow> </mml:msub> </mml:math> m − 3 , and pH 4, reaching a MB degradation of 98% and a COD reduction of 79% at 150 min. The high activity of the Nb 2 O 5 monolith catalyst remained constant after 10 catalytic tests.