A photocatalytic membrane reactor for gas-phase reactions using porous titanium oxide membranes

• Published in: Catalysis today Vol. 82; no. 1; pp. 41 - 48
• Main Authors: Tsuru, Toshinori, Kan-no, Takehiro, Yoshioka, Tomohisa, Asaeda, Masashi
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 30.07.2003; Elsevier Science
• Subjects: Applied sciences; Chemical engineering; Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Membrane reactor; Membranes; Methanol; Photocatalysis; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Porous membrane; Reactors; Titanium oxide; Membrane reactor; Titanium oxide; Porous membrane; Photocatalysis; Methanol; Transition metal compounds; Alkanol; Alcohol; Gaseous phase reaction
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/S0920-5861(03)00200-1

Photocatalytic membrane reactors using porous titanium oxide membranes having pore sizes of several nanometers were utilized for a gas-phase reaction of methanol. Air mixed with methanol (MeOH) vapor, the concentration of which was controlled in the range of 500–6000 ppm, was fed to the photocatalytic membrane reactor in the range of 50–500 cm 3/min using several types of flow patterns. Photocatalysis with membrane permeation resulted in a large decomposition rate, compared to photocatalysis without membrane permeation. The characteristics of the reaction such as decomposition ratio of MeOH, the conversion of the decomposed MeOH to CO 2 and H 2O were found to be a function of the residence time in the reactor. The photocatalytic reaction was analyzed based on pseudo-first-order kinetics to ascertain its simplicity, and the fitted curves were found to be in a relatively good agreement with the experimental data. Apparent rate constants with and without membrane permeation were 2.5 and 1.5×10 −6 m s −1, respectively, indicating that the performance of the photocatalytic reaction system with membrane permeation was enhanced.