Effect of rheological properties of mesophase pitch and coal mixtures on pore development in activated carbon discs with high compressive strength

摘要

We measured the rheological properties of mesophase pitch + coal mixtures at temperatures up to 873 K and used quench tests during carbonization to observe the effects of coal particles on foaming and pore development in activated carbon discs (ACD). We observed that high ratios of coal to pitch increased the mixture's viscosity in a low pressure foaming process, which restricted growth of large bubbles during foaming and produced stronger carbon monoliths. The highest strength ACD, with compressive strength of 56 +/- 3 MPa, was obtained using a pitch to coal mass ratio of 1:2 (bulk density = 0.91 g.cm(-3) and surface area = 579 +/- 37 m(2.)g(-1)). The adsorption capacities of CO2, CH4, and N-2 of the ACDs prepared with a mesophase pitch to coal ratio of 1:2, measured on a gravimetric adsorption apparatus, at 298 K and pressures up to 4000 kPa were 3751 mol.m(-3) CO2, 2107 mol.m(-3) CH4, and 1691 mo.m(-3) N-2. These adsorption results suggest the activated carbon discs have potential as structured adsorbents for gas separation or storage applications.