A fluidized bed photoreactor exploiting a supported photocatalyst with adsorption pre-concentration capacity

Abstract

Laboratory and small pilot scale fluidized bed photoreactors are described that utilize an integrated photocatalyst adsorbent (IPCA) mounted on porous silica beads as support protecting against IPCA attrition. The active material is Degussa P-25 TiO 2 bound to a Silicalite I zeolite adsorbent. Operating conditions for fluidization that achieves uniform illumination of photoactive particles are determined. Axial and multi-lamp configurations are compared. The small pilot reactor is calibrated against the laboratory reactor. Sub-stoichiometric acceleration of phenol oxidation by H 2 O 2 was observed.

Some Observations on the Development of Superior Photocatalytic Systems for Application to Water Purification by the “Adsorb and Shuttle” or the Interphase Charge Transfer Mechanisms

“…The chosen adsorbent is the high silica zeolite ZSM-5 in a configuration similar to the system of Vaisman et al . [5] designed as an adsorbent for photocatalytic regeneration. ZSM-5, with a highly hydrophobic surface, presents an adsorption profile resembling activated carbon, but weaker for some highly hydrophobic molecules and stronger for more polar organics.…”

“…This resembles the systems described in Vaisman et al . [5] that were used to construct an adsorbent to be regenerated photocatalytically. Since good results are achieved with an excess of adsorbent over TiO 2 , the adsorbent that is regenerated may be a good A/S target.…”

“…Vaisman et al . [5] reported that as the adsorption capacity increased, the photocatalytic kinetics decreased proportionately.…”

Structures and Photocatalytic Properties of Crystalline Titanium Oxide‐Dispersed Nanoporous Glass–Ceramics

“…Various forms of TiO 2 such as powders, coating films, and composites with heterointerfaces have been studied so far 2–6 . Among them, adsorbents modified with TiO 2 have attracted considerable attention because they can be applied to air and/or water purification, antifouling protection, bleaching, and other processes 7–10 . TiO 2 has a low adsorption ability.…”

Preparation of porous titanium phosphate glass-ceramics for NH3 gas adsorption with self-cleaning ability

“…6 Various types of adsorbents modified with photocatalytic materials have been widely investigated since they can be used for applications to air-and/or water-purification, antifouling protection and bleaching. 7,8 Among them, hydroxyapatite (HAp)/TiO 2 composites show good adsorption and photodecomposition properties for polluting materials such as bacteria and toxic chemical compounds. [9][10][11][12][13] However, the chemical degradation of HAp under acidic conditions limits the industrial application of the HAp/TiO 2 composites.…”