Methanol Carbonylation on Rh/C and Rh/NaX Catalysts

• Main Authors: Jing-Yang Lin, 林敬堯
• Other Authors: Tuan-Chi Liu
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/90026584934400721326

碩士 === 國立臺灣科技大學 === 化學工程研究所 === 83 === The carbonylation of methanol on Rh/NaX and Rh/C catalysts was studies. The influences of the reaction temperature, the time, the reduction of catalysts as well as the presences of iodide and water on this reaction was examined. The catalysts also characterized by BET surface, CO absorption and ESCA. Rh/NaX catalyst lost its activity at a reaction temperature 453K while the activity of Rh/C continued to increase with the temperature. Reducing the catalysts prior to the carbonylation resulted in a substantial loss of the activity of Rh/NaX but not of Rh/C.The main cause of the loss on Rh/NaX was discovered as the reduction of Rh(III) to Rh(0). Methyl iodide was found to be essential in the reaction. No reaction could proceed without the iodide.Adding water to the feed decreased the activity of Rh/NaX and slightly increased the activity of Rh/C. In addition to the effect on the activity, the water could also increased the of acetic acid on Rh/C. Increasing the contact time, as increased the conversion of methanol.The selectivity of acetic on the two catalysts was differently affected by the time. A significant enhancement in the selectivity was discovered on the Rh/C while there was almost no change in the selectivity on Rh/NaX.