Development of a doped titania immobilised thin film multi tubular photoreactor

Abstract

CopyrightItems in 'OpenAIR@RGU', Robert Gordon University Open Access Institutional Repository, are protected by copyright and intellectual property law. If you believe that any material held in 'OpenAIR@RGU' infringes copyright, please contact openair-help@rgu.ac.uk with details. The item will be removed from the repository while the claim is investigated. "NOTICE: this is the author's version of a work that was accepted for publication in Applied Catalysis B: Environmental. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in APPLIED CATALYSIS B: ENVIRONMENTAL, [VOL 130, (2013) ABSTRACTThis paper describes a novel doped titania immobilised thin film tubular photoreactor which has been developed for use with liquid, vapour or gas phase media. The current approach to photocatalyst and photoreactor development is firmly based on the principles of surface area. This dictate greatly limits the applicability of any semi-conductor photocatalyst in industrial applications, as a large surface area equates to a powder catalyst. This work aims to show that the development of a thin film coating, doped with a rare earth element, and a novel photoreactor design produces a photocatalytic degradation of a model pollutant (Methyl Orange) equal to that of P25 TiO 2 . It will show that doped thin film tubes in a novel reactor configuration can produce a degradation rate of 95 % after 90 minutes under UV irradiation and 70 % under visible irradiation with no downstream processing required. The use of lanthanide doping is reported here in the titania sol gel as it is thought to increase the electron hole separation therefore widening the potential useful wavelengths within the electromagnetic spectrum. Increasing doping from 0.5 % to 1.0 % increased photocatalytic degradation by ~17 % under visible irradiation. A linear relationship has been seen between increasing reactor volume and degradation which would not normally be observed in a typical suspended reactor system.

Degradation of microcystin-LR and cylindrospermopsin by continuous flow UV-A photocatalysis over immobilised TiO2

“…The lab-scale continuous-flow reactor used in this study was previously described (Adams et al, 2013;Gbadamosi, 2019). The schematic diagram of the experimental reactor setup is shown in Fig.…”

Synthesis and characterization of nanosized NiO@Ti0.94V0.06O1.94B0.06 with enhanced photocatalytic activity under visible light

“…It is well known that ion doping usually introduces impurity energy levels within the energy band gap, which helps to enhance the visible light absorption owing to the reduced band gap [4]. Generally, doping with anions (e.g., B [5,6], C [7,8], N [9,10], and F [11,12]) introduces impurity energy levels above the valence band, while doping with transition metal cations (e.g., V [13,14], Fe [15], Cu [16], and rare earth element [17,18]) introduces impurity energy levels below the conduction band. In addition to mono-doping, codoping (e.g., B/N [19,20], N/V [4,21], B/F [22], and B/Ni [23] ) has been already achieved and studied.…”

Photocatalytic reforming of glycerol to H2 in a thin film Pt‐TiO2 recirculating photoreactor

“…Within the field of photocatalysis, there has always been a strong research focus on the synthesis of new materials; however, the deployment of such materials is also paramount. The advantages of thin film‐based systems including reduced downstream processing and increased viability for scale‐up, have been documented previously, 24 yet there are a number of limitations which must be overcome. The primary obstacle is eliminating mass transfer to ensure increased interaction between the catalyst and substrate.…”

“…Moreover, promoting sufficient light penetration and distribution coupled with complete catalyst surface irradiation is equally important. Previously this has been achieved by coating the catalyst onto a range of supports including glass rods and spheres, 24,25 optical fibres, 26,27 activated carbon, 28 rotating discs 29 and stainless steel 30 . A drawback to a number of thin film‐based systems is the reduced catalyst surface area which often equates to reduced activity.…”