10min:

B. S. LIU, Department of Chemistry, Tianjin University, Tianjin 300072, P.R. China and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong; LING LI, A. S.-C. CHEUNG, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong; C. T. AU, Department of Chemistry and Center for Surface Analysis and Research, Hong Kong Baptist University, Kowloon Tong, Hong Kong.

Reverse water-gas shift (RWGS) reaction over La₂NiO₄ catalyst was investigated during CH₄/CO₂ reforming by continuous wave (cw) cavity enhanced absorption spectroscopy (CEAS), a sensitive absorption technique. A cw-diode laser with wavelength in the 1.3 µm region and an optical cavity consists of a pair of high reflectivity mirrors (0.99995) were used in the experiment. Absorption lines of the J = 0 (Q branch) rotational transitions of the 2₀¹3₀¹ vibrational transition of CH₄ near 7510 cm^-1, and the J = 5, K_a = 0, K_c = 5 to J = 6, K_a = 2, K_c = 4 rotational transition of the 1₀¹3₀¹ vibrational transition of H₂O near 7511.29 cm^-1 were monitored. The results indicated that the RWGS reaction promoted the conversion of CO₂ and decreased the partial pressure of hydrogen. Our CEAS result confirms that the conversion of CO₂ is always 3-5% higher than CH₄ due to RWGS reaction. In addition, the effect of reaction temperature on RWGS was studied. The work described here was supported by a grant from the Research Grants Council of Hong Kong SAR, China (Project No. HKU7101/02P)