制备了以MgO和CaO为助剂的乙苯脱氢制苯乙烯用Fe-K催化剂,并考察了助剂对催化剂催化性能的影响. 应用SEM、XRD、TPR和Mssbauer谱等手段表征了MgO和CaO对活性前驱体K2Fe22O34 晶相形成及其表观体相结构的影响. 结果表明,引入MgO助剂,半径相近的Mg2+与Fe3+极易发生取代形成固溶体,使活性前驱体K2Fe22O34 晶相的形成温度有所降低,同时给体相结构引入氧空位,从而有利于乙苯发生晶格氧转移机理的脱氢反应,使催化剂活性提高. 引入CaO助剂,提高了K2Fe22O34 晶相的结晶度和苯乙烯选择性,但催化剂活性有所下降. CaO对Fe-K催化剂的还原有一定的阻碍作用,是催化剂的稳定性助剂.
参考文献
| [1] | Lee E H .[J].Catalysis Review,1973,8(02):285. |
| [2] | Pitzer E W .[P].US 2866790,1958. |
| [3] | Shibata K;Kiyoura T .[J].Journal of Catalysis,1969,13(01):103. |
| [4] | Hirano T .[J].Applied Catalysis,1986,26(1-2):65. |
| [5] | Hirano T .[J].Applied Catalysis,1986,28(1-2):119. |
| [6] | O'Hara F J .[P].US 3904552,1975. |
| [7] | Hirano T .[J].Applied Catalysis,1986,26(1-2):81. |
| [8] | Mihajlova A;Andreev A;Shopov D;Dimitrova R .[J].Applied Catalysis,1988,40(1-2):247. |
| [9] | Muhler M;Schütze J;Wesemann M;Rayment T Dent A Schlgl R Ertl G .[J].Journal of Catalysis,1990,126(02):339. |
| [10] | Muhler M;Schlgl R;Ertl G .[J].Journal of Catalysis,1992,138(02):413. |
| [11] | Kotarba A;Rozek W;Serafin I;Sojka Z .[J].Journal of Catalysis,2007,247(02):238. |
| [12] | Watson J M;Crabbe D;Coursen T S Jr .[P].US 4963343,1990. |
| [13] | Watson J M;Crabbe D;Coursen T S Jr .[P].US 4975267,1990. |
| [14] | Joseph Y.;Kuhrs C.;Ranke W.;Weiss W.;Schlogl R.;Ketteler G. .On the preparation and composition of potassium promoted iron oxide model catalyst films[J].Physical chemistry chemical physics: PCCP,2001(18):4141-4153. |
| [15] | 祝以湘.镁对氧化铁系脱氢催化剂相变温度的影响[J].厦门大学学报,1994(z1):180. |
| [16] | 祝以湘;封雷;陈荣钦 .[J].化学物理学报,1999,12(04):491. |
| [17] | Ito S.;Akashi K.;Michiue Y.;Watanabe M.;Kurosawa H. .CRYSTAL STRUCTURE AND ELECTRIC CONDUCTIVITY OF K+-BETA-FERRITE WITH IDEAL COMPOSITION KFE11O17[J].Solid state ionics,1996(2):745-750. |
| [18] | Ito S.;Makino I.;Koura N.;Akashi K.;Washio M. .ROLE OF POTASSIUM IONS IN HUMIDITY SENSITIVITY OF K+-BETA-FERRITE[J].Solid state ionics,1996(2):1005-1011. |
| [19] | Yang X;Weng S;Jiang K;Mao L Euang Y Jing K .[J].Hyperfine Interactions,1991,69(1-4):863. |
| [20] | Jiang K Y;Yang X L;Wu Z .[J].Hyperfine Interactions,1993,77(1-2):67. |
| [21] | Jiang K;Yang J;Hu B;Yang X Mao L Yuan Y Zhang G .[J].Hyperfine Interactions,1998,111(1-4):45. |
| [22] | 祝以湘,胡云行.Effects of Rare Earth Elements on Properties and Structure of WC-14TiC-8Co Cemented Carbide[J].JOURNAL OF RARE EARTHS,1994(02):118. |
| [23] | Reymond J P;Meriaudeau P;Teichner S J .[J].Journal of Catalysis,1982,75(01):39. |
| [24] | Lundin J;Holmlid L;Menon P G;Nyborg L .[J].Industrial and Engineering Chemistry Research,1993,32(11):2500. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%