Insight into essential channel effect of pore structures and hydrogen bonds on the solvent extraction of oily sludge.

In this study, solvent extraction experiments were conducted to investigate the channel effect of pore structures and hydrogen bonds by analyzing the desorption behavior of oil components. The highest oil recovery efficiency was 87.9 % under optimum conditions. Pore structure of oily sludge was analyzed by N2 adsorption-desorption analysis and scanning electron microscope (SEM) measurements. Mesopores of sludge inhibited the desorption of oil molecules by analyzing the pore width and cumulative pore volume of residual sludge in desorption process. In addition, saturates and aromatics were easily extracted from sludge, while the desorption rate and desorption efficiency of oily sludge were limited by resins and asphaltenes respectively through component analysis and kinetic analysis. Furthermore, channel effect of pore structures and hydrogen bonds was investigated in the desorption process of oily sludge, which also provided a guidance to selectively extract light components from oily sludge with high efficiency in industry processing.