Aluminas were prepared by precipitation of aqueous aluminum nitrate solution using ammonium carbonate and ammonium hydroxide as precipitation agent respectively. The prepared samples were characterized by TG/DTA, XRD,...Aluminas were prepared by precipitation of aqueous aluminum nitrate solution using ammonium carbonate and ammonium hydroxide as precipitation agent respectively. The prepared samples were characterized by TG/DTA, XRD, surface area, pore volume and average pore diameter and the results were compared. The activity and stability of the close-coupled catalysts supported by aluminas prepared by different precipitating agent were compated. The alumina formed by ammonium carbonate showed larger surface area, pore volume, average pore diameter, higher thermal stability and better support property than that formed by ammonium hydroxide. The precusor of NH4Al(OH)2CO3 in the ammonium cabonate process was responsible for the difference.展开更多
文摘Aluminas were prepared by precipitation of aqueous aluminum nitrate solution using ammonium carbonate and ammonium hydroxide as precipitation agent respectively. The prepared samples were characterized by TG/DTA, XRD, surface area, pore volume and average pore diameter and the results were compared. The activity and stability of the close-coupled catalysts supported by aluminas prepared by different precipitating agent were compated. The alumina formed by ammonium carbonate showed larger surface area, pore volume, average pore diameter, higher thermal stability and better support property than that formed by ammonium hydroxide. The precusor of NH4Al(OH)2CO3 in the ammonium cabonate process was responsible for the difference.
