Successful development of a new layered structure catalytic refractory paper

[China Packaging News] Catalysts are widely used in chemical and industrial production, and occupy an extremely important position in the modern chemical industry. The nano catalyst has small size, large specific surface area, high surface activity, and has excellent catalytic performance, which has aroused widespread interest and attention in recent years. But one of the difficulties is that in the liquid-phase catalytic reaction system, when the catalytic reaction is completed, it is difficult for the nano-catalyst powder to be separated from the liquid-phase reaction system, making the recovery and utilization of the catalyst difficult and the high recovery cost. In addition, the catalyst nanoparticles are prone to severe agglomeration in the liquid phase reaction system, resulting in a significant reduction in the catalytic performance of the catalyst.

Recently, Zhu Yingjie, a researcher at the Shanghai Institute of Ceramics, Chinese Academy of Sciences, and Xiong Zhichao, an assistant researcher, have grown in situ on aqueous hydroxyapatite nanowires in aqueous solutions at room temperature based on the research work on new inorganic refractory paper Gold nanoparticles, successfully developed a new type of layered structure catalytic refractory paper with good flexibility. The loading amount of the nano-gold catalyst in the catalytic refractory paper is controllable and uniformly dispersed, which can effectively prevent the agglomeration of gold nano-particles and improve the catalytic activity. In addition, in the new type of catalytic refractory paper, hydroxyapatite ultra-long nanowires form a nanoporous network structure and layered structure through self-assembly, which can greatly improve the chance of contact with the nanocatalyst when the reactant flows through in the catalytic reaction. Significantly improve catalytic efficiency. The new type of catalytic refractory paper is easy to achieve efficient separation and recycling from the liquid phase reaction system. After the catalytic reaction is completed, as long as the catalytic refractory paper is removed from the solution, the nano catalyst can be recovered and reused conveniently and quickly, which can greatly reduce costs. More importantly, the new catalytic refractory paper has excellent high temperature resistance and fire resistance, even if it is burnt for a long time in the fire, it can still be kept intact. The new catalytic refractory paper has good high-temperature catalytic stability, and can still maintain high catalytic activity after high-temperature treatment. In addition, the new catalytic refractory paper can be used repeatedly and for a long time, and still maintain high catalytic activity. Research results were published in the British Chemical Society "Journal of Materials Chemistry A" (Journal of Materials Chemistry A , 6,5762-5773 (2018)) magazine.

The new layered structured refractory paper exhibits excellent catalytic performance in continuous flow catalytic reactions. Experiments show that, at room temperature, 4-nitrophenol and an aqueous solution containing sodium borohydride was poured long novel catalytic refractory paper, as soon as the aqueous solution flowing through the filter paper refractory catalyst, the catalytic reaction is complete, 4-nitrophenyl The base phenol is converted to 4 -aminophenol, the catalytic reaction is fast and the catalytic efficiency is very high ( ——100% ). Similarly, using continuous flow catalytic reaction, the new type of catalytic refractory paper can also achieve efficient and rapid degradation of various organic dyes such as rhodamine B , methyl orange, etc. As long as the aqueous solution contaminated with organic dyes is poured on the catalytic refractory paper, it flows quickly. It can achieve continuous efficient and rapid purification of sewage. In addition, the research team also achieved the scale-up preparation of 10-stage reactor with ultra-long hydroxyapatite nanowires and the preparation of large-size new layered structured refractory paper. The prepared large-size catalytic refractory paper has good uniformity and Repeatable high catalytic activity.

The new inorganic refractory paper based on hydroxyapatite ultra-long nanowires is an excellent high temperature resistant catalyst carrier, which can achieve efficient loading, uniform dispersion and tight fixation of various nanocatalysts. The prepared new layered structured catalytic refractory paper has excellent high temperature resistance, and is especially suitable for a variety of liquid phase and gas phase catalytic reactions at high temperatures, and can be recycled and used for a long time, in chemical engineering, industrial production, industrial Exhaust gas purification, automobile exhaust purification, sewage treatment and other fields have good application prospects.

The research work was supported by the National Natural Science Foundation of China and Shanghai Science and Technology Commission.