CAJ | 학술논문

苯氨基甲酸甲酯(MPC)是非光气合成MDI的重要中间体，苯胺(AN)、尿素和甲醇一步合成MPC是一条绿色的反应工艺。首先考察了部分金属氧化物和Lewis酸对该反应的催化性能，发现经400℃焙烧2 h的γ-Al2O3催化活性最好。其次，确定了γ-Al2O3催化合成 MPC 的适宜反应条件：n(AN)：n(γ-Al2O3)：n(Urea)：n(MeOH)=1：0.12：5：75，初压0.6 MPa，反应温度180℃，反应时间2 h。在此条件下，苯胺转化率为88.4%，MPC选择性为84.6%。在此基础上，考察了γ-Al2O3的催化稳定性，发现重复使用五次后，其催化性能没有明显的下降。最后，对γ-Al2O3的催化机理进行了研究，发现γ-Al2O3催化苯胺、尿素和甲醇一步合成MPC反应主要沿着以氨基甲酸甲酯为中间产物的路径进行。并据此提出了催化反应机理。
분안기갑산갑지(MPC)시비광기합성MDI적중요중간체，분알(AN)、뇨소화갑순일보합성MPC시일조록색적반응공예。수선고찰료부분금속양화물화Lewis산대해반응적최화성능，발현경400℃배소2 h적γ-Al2O3최화활성최호。기차，학정료γ-Al2O3최화합성 MPC 적괄의반응조건：n(AN)：n(γ-Al2O3)：n(Urea)：n(MeOH)=1：0.12：5：75，초압0.6 MPa，반응온도180℃，반응시간2 h。재차조건하，분알전화솔위88.4%，MPC선택성위84.6%。재차기출상，고찰료γ-Al2O3적최화은정성，발현중복사용오차후，기최화성능몰유명현적하강。최후，대γ-Al2O3적최화궤리진행료연구，발현γ-Al2O3최화분알、뇨소화갑순일보합성MPC반응주요연착이안기갑산갑지위중간산물적로경진행。병거차제출료최화반응궤리。
Methyl N-phenyl carbamate (MPC) is a key intermediate for the manufacture of methylene diphenyl diisocyanate (MDI) by non-phosgene method, and one-step synthesis of MPC from aniline(AN), urea and methanol is a green technology. In this paper, the catalytic performance of metal oxides and Lewis acid in the reaction of MPC synthesis was evaluated at first and it was found that theγ-Al2O3 calcined at 400℃ for 2 h presents the best catalytic activity. Under the suitable reaction conditions of initial pressure of 0.6 MPa, reaction temperature of 180℃, reaction time of 2 h, and n(AN):n(γ-Al2O3):n(Urea):n(MeOH)=1:0.12:5:75, the conversion of aniline and the selectivity of MPC are 88.4%and 84.6%, respectively. Additionally,γ-Al2O3 could be reused five times without significant deactivation, which indicates that it has satisfactory stability in this reaction. Studies on the catalytic mechanism reveal that the reaction proceeds mainly along the process of forming the methyl carbamate (MC) as intermediate, and the reaction mechanism for MPC synthesis was proposed.