Treatment of bicomponent textile dyes using combined photocatalysis and adsorption process made from residue-based reactor and adsorbent material

Abstract

The present work evaluated the degradation efficiency by photocatalysis and the removal by adsorption with a sequential combination of these processes for the treatment of a bicomponent mixture of methylene blue and remazol yellow gold RNL 150 dyes. A recirculation system made from post-consumer plastic box residues was applied, in addition with supports for the TiO P25, made with post-consumption aluminum seals. The UV_c/H₂O₂/TiO_2supp system showed a 93.15% degradation after 360 min in the preliminary study. After applying a factorial design 2³, a 100% color removal was reached in 210 min, for the adsorptive process in lemon peel activated with H₃PO₄ and HCl (1.6 g L⁻¹). The combined system, consisting of photocatalysis followed by adsorption as a polishing treatment, proved to be more efficient, promoting a degradation of 100% of the chromophor groups and 90.4% for the aromatic groups, in 105 min, a shorter time than either individual process. In addition, a textile effluent subjected to the combined system promoted degradation/removal of 60% (254 nm) and 82% (663 nm) for the evaluated wavelengths.

Keywords:

• Adsorption
• combined process
• methylene blue
• photocatalysis
• remazol yellow gold RNL 150

Acknowledgments

We acknowledge English revision by Sidney Pratt, Canadian, BA, MAT (The Johns Hopkins University), RSAdip (TEFL) (Cambridge University).

Additional information

Funding

We acknowledge financial support from FINEP, National Council for Scientific and Technological Development, CNPq/INCT-EMA, PETROBRAS-ANP-LITPEG (contract 0050.0078506.12.9), CAPES/PROCAD (Project 88881.068433/2014-01) and characterization support from CETENE.