Direct Synthesis of Diethyl Carbonate from CO<sub>2</sub> over ZnO@Na<sub>3</sub>PW<sub>12</sub>O<sub>40</sub> Heterogeneous Material

Abstract

At present, the world is facing two major problems: energy crisis and CO₂ emission. Diethyl carbonate is an effective gasoline additive which can greatly improve octane number. The route of diethyl carbonate synthesis from CO₂ is green and economical technique, which can effectively solve both energy crisis and CO₂ emission problems together. However, the design and preparation of catalysts is the core and key to realize the conversion from CO₂ to diethyl carbonate. This paper mainly described a novel synthesis of ZnO@Na₃PW₁₂O₄₀ heterogeneous material that applied in the direct synthesis of diethyl carbonate from CO₂ and ethanol. The special pore and channel structure of Na₃PW₁₂O₄₀ was used to maximize the catalytic capacity of ZnO material. The prepared catalysts were fully characterized by means of temperature-programmed desorption (TPD) and X-ray powder diffraction (XRD). The properties of acid-base sites on the surface of ZnO@Na₃PW₁₂O₄₀ were measured by temperature-programmed desorption technique. The catalytic performance over ZnO@Na₃PW₁₂O₄₀ heterogeneous material was examined on micro-reactor. The experiment results indicated that synthesized novel ZnO@Na₃PW₁₂O₄₀ heterogeneous material had large number of acid-base sites and high catalytic activity. This novel ZnO@Na₃PW₁₂O₄₀ catalyst had great ability to realize the effective conversion from CO₂ to diethyl carbonate. This technology not only improved the utilization rate of energy materials, but also reduced CO₂ emissions.