Low carbon monoxide wide temperature change catalyst

Title: Low carbon monoxide wide temperature change catalyst
　　Author: Li Yunfeng
　　Degree awarded: Shandong University of Technology
　　Keywords: catalyst;; copper-zinc-chromium;; additives;; shift reaction
　　Summary:
　　In this paper, coprecipitation of copper and zinc chrome wide gentle low-temperature shift catalyst, a detailed discussion of copper-zinc-chromium catalyst preparation process conditions, the type of filter aids, and appropriate dosage, and in-depth study of these Magnetic lifter factors on the catalyst performance. The results show that: when the Cu: Zn: Cr is 12:17:57, and the mixture in a concentration of 1 mol / L, and in a temperature of 70 ~ 80 ℃, and in time of 40min, PH = 7.5 ~ 9.0, roasting temperature of 450 ℃, roasting time of 3h, the catalyst activity is very high. When the additive content were Ce: 0.8%, La: 0.6%, the catalyst significantly improved heat resistance. The low water-gas ratio in the catalyst under the conditions of activity was higher in the water-gas ratio of 2, the highest activity, did not have any side effects occur.
　　Different precipitation temperature, precipitant, precipitation method, calcination temperature, space velocity and the reduction of carbon gas and other preparation parameters on the Cu-Zn-Cr catalysts have a certain impact. With Na2CO3 solution as precipitating agent, with a positive addition, CO and H2 gas mixture to restore the best performance from the catalyst, CO conversion and hydrogen production rate of the best.
　　In this experiment, the TG / DTA thermal analyzer, nitrogen adsorption analyzer, X-ray powder diffraction, TEM, TPR and other means of testing the catalyst crystal phase, particle size and surface area were analyzed. The results show that: the optimized catalyst in addition to Cu-Zn-Cr solid solution formation in vitro, as well as some amorphous material existence. Of Cu in the copper-based catalyst is the main active component, Zn stabilizing role of CuO. http://www.999magnet.com/products/131-magnetic-lifter   Catalyst particle size is smaller and more uniform than the surface area of ​​catalyst 64.7277m2 / g. Rare earth addition on Cu-Zn-Cr catalysts have a certain impact. XRD results show that: Ce2O3 accession unchanged CuO-ZnO-Cr2O3 catalyst crystal phase of each component. The addition of rare earth catalyst active component to reduce the aggregation and improve the thermal stability of the catalyst. In addition, the CuO-ZnO-Cr2O3 catalyst thermal stability test, the catalyst within the 60h showed good stability.
　　Degree Year: 2010