Carbon-Mineral Adsorbent from Petroleum Pitch and Precipitated Colloidal Silica

Abstract

The carbon-mineral adsorbent was prepared according to a two-stage scheme, which, despite the hydrophilic nature of the surface of colloidal silica, made it possible to prepare pellets with a high specific surface area and compressive strength of up to 70 m2/g and 8 MPa, respectively. The proposed method consists in mixing petroleum pitch and colloidal silica in the first stage, followed by granulation and carbonization (at 1000 °C); the resulting carbon-mineral material is crushed and mixed with petroleum pitch in the second stage, after which it is also granulated and carbonized (at 700 °C). Based on the obtained carbon-mineral sorbent, a highly porous carbon adsorbent is produced by etching the silicate base in a concentrated solution of sodium hydroxide during boiling. The total pore volume of the obtained samples reached 3.5 cm3/g.