A novel experimental bench dedicated to the accurate radiative analysis of photoreactors: The case study of CdS catalyzed hydrogen production from sacrificial donors

• A novel and accurate experimental bench for the study of photoreactions is presented.
• Complete characterization of the bench has been done: RTD, photon flux density…
• H2 production rates are accurately determined by pressure measurements.
• Experimental results show a quantum yield fall with incident photon flux density rise.

This article is dedicated to the presentation of a novel experimental bench designed to study the photoproduction of H2. It is composed of three main parts: a light source, a fully equipped flat torus reactor and the related analytical system. The reactor hydrodynamic behaviour has been carefully examined and it can be considered as perfectly mixed. The photon flux density is accurately known thanks to reconciled quantum sensor and actinometry experiments. The incident photon direction is perpendicular to the reactor windows; in such a configuration the radiative transfer description may be properly approximated as a one dimensional problem in Cartesian geometry. Based on accurate pressure measurement in the gas tight photoreactor, the production rates of H2 (using CdS particles in association with sulfide and sulfite ions as hole scavengers) are easily and trustingly obtained.First estimations of apparent quantum yield have proven to be dependent on mean volumetric rate of radiant light energy absorbed hence demonstrating the need for the use of a radiative transfer approach to understand the observed phenomena and for the proper formulation of the thermo-kinetic coupling.