SiO_(2)网络限域CuO纳米晶的甲醛乙炔化性能研究

Study on formaldehyde ethynylation performance of CuO nanocrystalline confined in SiO_(2) networks

甲醛与乙炔缩合制取1,4-丁炔二醇是乙炔化工的重要方向。探讨铜基催化剂在甲醛乙炔化反应中的演变及催化作用机制,并开发更高效的甲醛乙炔化催化剂是一个值得科学与产业界关注的课题。本工作在前期页硅酸铜催化剂制备及甲醛乙炔化性能研究基础上,进一步通过热处理温度的调整,在焙烧温度为650℃时,构筑了限域于SiO_(2)网络结构中的CuO纳米晶催化剂。CuO纳米晶适宜的化学环境,使其在甲醛乙炔化反应初始阶段快速形成活性炔化亚铜,获得了1,4-丁炔二醇收率80%左右的结果,克服了页硅酸铜物种转化为炔化亚铜速率慢、诱导期长的弊端。SiO_(2)网络结构的限域作用也进一步抑制了活性组分的流失,在6次套用实验中1,4-丁炔二醇收率几乎不变,呈现出良好的使用稳定性。

The synthesis of 1,4-butynediol by the condensation of formaldehyde and ethynyl is an important reaction in ethynyl chemical industry.The study on catalytic mechanism and evolution of Cu-based catalysts in the acetylene reaction of formaldehyde has attracted more and more attention.In this work,on the basis of the preparation of copper silicate catalyst and the performance of formaldehyde ethynylation in the previous stage,and further through the adjustment of the heat treatment temperature,when the calcination temperature is 650℃,a CuO nanocrystalline catalyst confined in the SiO_(2) network structure was constructed.Due to suitable chemical environment of CuO nanocrystals,cuprous ethynylation is formed rapidly in the initial stage of the formaldehyde ethynylation reaction,and the yield of about 80%of 1,4-butynediol is obtained.The initial activity is higher than that of the same kinds of catalyst.More importantly,the catalyst showed good stability due to the confined effect of the SiO_(2) network structure.The yield of 1,4-butynediol was almost unchanged in 6 application experiments,showing good stability.