| 摘要: |
| 基于未改性Pt/Al20,催化剂探索环己酮二聚物脱氢反应体系，针对反应产物的分布特点使用多种钾助剂对催 化剂性能进行调变，采用吡啶吸附红外(Py-丨R)、氢氧滴定< H2-02 Titration,HOT)、X射线光电子能谱(XPS)、程序升 温还原(TPR)等对Pt-K/A!20,催化剂中钾助剂的促进作用机制进行研究。结果表明:在合适的条件下使用钾助剂 可以大幅提高邻苯基苯酚(0PP)的选择性(最高可达94%);钾助剂对铂基脱氢催化剂的促进作用体现为2个方面， 一是削弱氧化铝载体酸性，可以通过抑制酸中心导致的副产物生成时提高目的产物0PP的选择性，二是钾与铂中心 存在较强的相互作用，特别是电性促进作用(EP);碱性较强的K2C03改性效果最好。 |
| 关键词: 邻苯基苯酚 脱氢 铂 钾 氧化铝 促进作用 |
| DOI：10.3969/j.issn.1673-5005.2012.03.029 |
| 分类号:TQ 420 |
| 基金项目:家“973”歌点基础研究发展计划项目(2010CB226905);教育部创新闭队“重质油高效转化的绿色化学与工程”项目；国家自然科学准金项M(21106185) |
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| Pt-K/AI203 dehydrogenation catalyst for synthesis of o-phenyl phenol(I): promotion effect of potassium species |
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LI Yan-peng1,2,LIU Da-peng2,LIU Chen-guang1,2
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(1. State Key Laboratory of Heavy Oil Processing in China University of Petroleum, Qingdao 266580, China;2. Key Laboratory of Catalysis, CNPCt China University of Petroleum, Qingdao 266580, China)
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| Abstract: |
| The reaction system of cyclohexanone dimer dehydrogenation over non-modifieU Pt/Al203 catalyst was investigated. According to the reaction products distribution characteristics, a variety of potassium additives were adopted to modify Pl/Al203 catalysts. The promotion effect of the potassium species on the Pt/ AI2 03 catalyst was studied by using several characterization methods such as pyridine acisorplion infrared spectroscopy ( Py-IR), H2-02 titration (HOT)，X-ray photoelectron spectroscopy ( XPS) and temperature-programmed reduction (TPR). The results show that the OPP selectivity can be greatly improved under proper dosage and kind of potassium additive. The promotion effect from the potassium species can be interpreted in two ways. Firstly, the introduction of basic potassium additives, such as K2C03，can greatly suppress the acidity of alumina support ( confirmed from Py-IR results), inhibit the by-products resulted from the acidic center and improve the OPP selectivity. Secondly, the potassium species has strong interactions with the Pt center, especially the electrical promotion (EP) effect. Basic potassium additive such as K2C03 is more effective since it exhibits the promotion effect from both ways. |
| Key words: o-phenyl phenol dehydrogenation Pt K A1203 promotion effect |
