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第 35 卷第 10 期                            精   细   化   工                                 Vol.35, No.10
             2018 年 10 月                             FINE CHEMICALS                                Oct.   2018


              催化与分离提纯技术
                           高分散 Ru-PEG /NaY 催化对硝基甲苯
                                                       x

                                          加氢制对甲基环己胺



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                             李红伟 ,李泽宇 ,            2   贠宏    飞  1 ,季   东 ,李贵贤
                 (1.  兰州理工大学  石油化工学院,甘肃  兰州  730050;2.  兰州大学  化学化工学院,甘肃  兰州  730000)
                 摘要:以聚乙二醇[PEG(400)]为分散剂、(NH 4 ) 2 CO 3 水溶液为沉淀剂,采用浸渍沉淀法,制备了高分散的
                 Ru-PEG x /NaY 催化剂,利用 XRD、TEM、H 2 -TPR、ICP-AES 及 XPS 等手段对样品进行了表征。结果表明:适
                                                                                   3+
                                                      3+
                                             3+
                 量的(7.5 mL)PEG 可以包裹住 Ru ,增大 Ru 之间的排斥力,从而有效地阻止 Ru 的团聚。以对硝基甲苯液
                 相(PNT)加氢制对甲基环己胺(PMC)为探针反应,以 PNT 转化率和 PMC 选择性为指标考察了不同 Ru 催化
                 剂的催化性能。结果表明:Ru-PEG 7.5 /NaY 的催化性能最优,在催化剂 0.50 g、反应时间 35 min、H 2 压力 3.5 MPa、
                 反应温度 160 ℃、对硝基甲苯 5.00 g、搅拌速率 900 r/min、异丙醇 300 mL 的条件下,PNT 的转化率为 100%,
                 PMC 的选择性高达 95.0%。此外,发现 Ru-PEG 7.5 /NaY 催化剂重复使用 5 次后,活性未明显降低,说明其稳定
                 性良好。
                 关键词:对硝基甲苯;Ru 催化剂;聚乙二醇;加氢反应;对甲基环己胺;催化技术
                 中图分类号:TQ421.1      文献标识码:A     文章编号:1003-5214 (2018) 10-1673-06



                    Hydrogenation of p-Nitrotoluene to p-Methyl-cyclohexylamine Over
                                     High Dispersion Ru-PEG x/NaY Catalyst


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                               LI Hong-wei , LI Ze-yu , YUN Hong-fei , JI Dong , LI Gui-xian
                 (1. School of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, Gansu, China; 2. College of
                 Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, Gansu, China)
                 Abstract: A  high dispersion  Ru-PEG x/NaY catalyst was prepared  by impregnation-precipitation method
                 using PEG (400)  as dispersant  and  (NH 4) 2CO 3 as precipitant. The samples were characterized by XRD,
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                 TEM, H 2-TPR, ICP-AES and XPS. The results showed that the suitable PEG (7.5 mL) could trap the Ru
                                                       3+
                 ions and increas the  repulsion among  Ru  ions, consequently, which could  effectively  prevent
                                      3+
                 agglomeration of the Ru  particles. The catalytic performances of different samples were evaluated via
                 liquid-phase hydrogenation of p-nitrotoluene (PNT) to p-methyl-cyclohexylamine (PMC) reaction, with the
                 PNT conversion and PMC selectivity as indicator. The results indicated that Ru-PEG 7.5/NaY exhibited the
                 best catalytic performance. The PNT conversion and the selectivity of PMC were found to be as high as 100%
                 and 95.0% under the optimum conditions of Ru-PEG x/NaY dosage 0.50 g, reaction time 35 min, pressure of
                 H 2 3.5 MPa, reaction temperature 160 ℃, amount of PNT 5.00 g, stirring rate 900 r/min, and isopropyl
                 alcohol  300  mL. In addition, it  was found that the  activity of Ru-PEG 7.5/NaY was not  significantly
                 decreased after five repeated recycling runs, indicating Ru-PEG 7.5/NaY catalyst had good stability.
                 Key words:  p-nitrotoluene;  Ruthenium catalyst; polyethylene glycol; hydrogenation reaction;  p-methyl-
                 cyclohexylamine; catalysis technology


                 对甲基环己胺是合成医药、橡胶、工业催化剂、                         造纸和染料等领域,工业上通常由还原对甲苯胺或
                                                                                     [1]
            防水剂等的重要中间体,同时也被广泛应用于汽车、                            直接还原对硝基甲苯制备 。

                 收稿日期:2017-09-25;  定用日期:2017-12-14; DOI: 10.13550/j.jxhg.20170775
                 作者简介:李红伟(1988—),男,博士生。联系人:李贵贤(1966—),男,教授,E-mail:ligxgd@163.com。
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