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Para-tert-butyl phenol (p-TBP) and 2,4-di-tert-butyl phenol ( 2,4-DTBP) are wi.dely used for the preparation of antioxidants. Zeolite catalysts showed good performance for the synthesis of p-TBP and 2,4-DTBP. In this work, zeolite H-mordenite (HM) catalyst was prepared and the alkylation of phenol with tert-butyl alcohol over zeolite HM catalyst was investigated at different reaction conditions. It is found that increasing temperature enhances the selectivity to p-TBP and the optimum reaction temperature for phenol conversion is 438 K. Increasing flow rate decreases phenol conversion apparently while the selectivity to p-TBP has a little increase. The suitable tert-butyl alcohol/phenol molar ratio is 2. Lower alcohol/phenol molar ratios are beneficial to p-TBP while higher ones are helpful for producing 2,4-DTBP. 相似文献
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介绍了利用镗床进行高精度销孔加工的技术.根据精镗销孔工序的加工特点,从设备、刀具系统等方面分析敢影响销孔加工精度的主要原因,并提出了相应的改进措,该加工方法已经在生产实践中得到了应用. 相似文献
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