| 摘要 |
Liquid hydrocarbons are subjected to countercurrent contact with adsorbent by passing the adsorbent downwardly as a columnar mass of gravitating particles (4-100 mesh in size), through a confined treating zone, introducing the liquid hydrocarbons upwardly through the columnar mass, from a plurality of horizontally spaced apart points substantially uniformly distributed with respect to the horizontal cross-sectional area of the columnar mass, and at a rate insufficient to interfere with the countercurrent flow of the adsorbent and withdrawing the liquid hydrocarbons and adsorbent from the upper and lower sections respectively of the columnar mass, minimum numbers N of points of introduction of the liquid hydrocarbons having the value N = 96.7A/L1.97 where L is the height in feet and A the horizontal cross-sectional area in square feet of the columnar mass. The liquid hydrocarbons treated may be lubricating oils (which may be diluted with naphtha to reduce their viscosity or lighter petroleum fractions of low asphalt content and the treatment may effect decolorization, neutralization, removal of suspended colloidal or dissolved impurities such as carbon, coke or oxygen and nitrogen containing impurities and other gum forming compounds, and improvement of demulsibility properties. The process may also be employed for the separation of hydrocarbon mixtures by adsorption. Suitable adsorbents are Fuller's earth, bauxite, bentonite, bone char, charcoal, magnesium silicate, heat- and acid-activated kaolin, activated carbon, silica gel, alumina gel and silica-alumina gel. Various constructions of apparatus for contacting the liquid hydrocarbons with adsorbents are described. Specifications 576,058, 770,391 and 770,392 are referred to. |
