Strategies to reduce mass and photons transfer limitations in heterogeneous photocatalytic processes: Hexavalent chromium reduction studies

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Belisa A. Marinho (Author) FEUP; Raquel O. Cristóvão (Author) FEUP; Ridha Djellabi (Author) FEUP; Ana Caseiro (Author) FEUP; Sandra M. Miranda (Author) FEUP; José M. Loureiro (Author) FEUP; Rui A.R. Boaventura (Author) FEUP; Madalena M. Dias (Author) FEUP; José Carlos B. Lopes (Author) FEUP; Vítor J. P. Vilar (Author) FEUP

Journal

Title: Journal of Environmental Management

Vol. 217

Pages: 555-564

ISSN: 0301-4797

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 8 Citations

ISI Web of Science

Scopus - 22 Citations

Scientific classification

CORDIS: Technological sciences > Engineering > Chemical engineering

FOS: Engineering and technology > Environmental engineering

Associated Projects

LSRE-LCM - Laboratório de Processos de Separação e Reação - Laboratório de Catálise e Materiais

Other information

Authenticus ID: P-00N-VN6

DOI: 10.1016/j.jenvman.2018.04.003

Abstract (EN): The current work presents different approaches to overcome mass and photon transfer limitations in heterogeneous photocatalytic processes applied to the reduction of hexavalent chromium to its trivalent form in the presence of a sacrificial agent. Two reactor designs were tested, a monolithic tubular photoreactor (MTP) and a micro-meso-structured photoreactor (NETmix), both presenting a high catalyst surface area per reaction liquid volume. In order to reduce photon transfer limitations, the tubular photoreactor was packed with transparent cellulose acetate monolithic structures (CAM) coated with the catalyst by a dip-coating method. For the NETmix reactor, a thin film of photocatalyst was uniformly deposited on the front glass slab (GS) or on the network of channels and chambers imprinted in the back stainless steel slab (SSS) using a spray system. The reaction rate for the NETmix photoreactor was evaluated for two illumination sources, solar light or UVA-LEDs, using the NETmix with the front glass slab or/and back stainless steel slab coated with TiO2-P25. The reusability of the photocatalytic films on the NETmix walls was also evaluated for three consecutive cycles using fresh Cr(VI) solutions. The catalyst reactivity in combination with the NETmix-SSS photoreactor is almost 70 times superior to one obtained with the MTP.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10