掺炼焦化汽油的重整预加氢催化剂研究

掺炼焦化汽油是扩大重整装置原料的重要途径之一。针对焦化汽油的特点,采用镁铝水滑石对氧化铝载体进行改性,一方面提高其比表面积和孔容从而提高其加氢活性;另一方面降低氧化铝载体酸含量,从而降低焦化汽油中不饱和烃类结焦的倾向。浸渍液中添加柠檬酸作为分散剂以提高金属组分在浸渍液中的分散性,通过添加硝酸调整pH值至1.5促进浸渍液中的金属组分与载体结合以提高其分散性。将自制催化剂与参比剂进行对比,自制催化剂的金属成本低于参比剂,且通过对掺炼焦化汽油的油品进行预加氢试验发现在低温度(280℃)、低氢油比(100)和低压力(2.5MPa)的工艺条件下,自制催化剂的活性优于参比剂。通过1 000 h的稳定性实验发现,自制催化剂的加氢活性仍具有较高的稳定性和活性,产物均能满足工业要求。

Pre-hydrogenation catalyst study in reforming of blended coking gasoline

Blending coking gasoline is one of the important ways to expand the feedstock of reformer.According to characteristics of coking gasoline,Mg-Al hydrotalcite was used to modifyalumina carrierto increase surface area and pore volume,so as to improve hydrogenation activity,and to decreaseacid contentof alumina carrier,so as to reducecoking tendency of unsaturated hydrocarbon.Citric acid was added as dispersant into dipping solution to improve dispersion of met al component.PH value was adjusted to 1.5 by adding nitric acid to promote metal component in the impregnating solution to combine with carrier to improve its dispersion. Metal cost of the catalyst was lower than reference agent.Catalyst activity under conditions of low reaction temperature (280 ℃),low hydrogen/oil ratio (100) and low pressure (2.5 MPa) was better than reference agent.Through stability test of 1 000 h,the self-made catalyst still had high stability and activity,and the products could meet industrial requirements.