Studies on properties of a ternary slurry prepared from semicoke modified with coal tar pitch

A novel approach was proposed for the efficient and environmentally responsible utilization of semicoke (SC) and coal tar pitch (CTP) through the formulation of semicoke‒coal tar pitch‒water ternary slurry (SCPWS), wherein SC was subjected to modification with CTP. The surface properties and pore structure of SC were meticulously examined by Fourier transform infrared spectroscopy, scanning electron microscopy, contact angle with water, and N2 adsorption-desorption isotherms. The empirical results revealed a substantial reduction in the porosity and hydrophilicity of SC following its modification with CTP. Furthermore, investigations into the adsorption behavior of dispersant and zeta potential were undertaken to elucidate the principles governing the alterations in the slurryability of SC before and after modification. The saturation adsorption capacities of dispersant on the surfaces of SC, CTP and modified SC were respectively 8.303, 2.227, and 3.691 mg·g−1, respectively. Under the condition of saturated adsorption of dispersant, the absolute value of zeta potential of SC particles increased from 56.5 mV to 75.5 mV after modification, enhancing the electrostatic repulsion between particles. Accordingly, a high-performance SCPWS was achieved, featuring a solid concentration of 68.56 wt%, a water separation rate of 2.67 wt%, a good fluidity of A + , and a pseudo-plastic rheological behavior.