Peat semicoking and hydrocracking

This work deals with thermochemical conversion of peat into solvent-soluble oil and volatile gaseous products by using pyrolysis and catalytical hydrocracking methods. Distribution of liquid compounds between solubilized in water, benzene, and in acetone was determined and as a result the oil yield as total solubles was calculated. Chromatographic and FTIR-spectroscopic methods were used to characterize the composition of conversion products. Investigation of peat pyrolysis regularities in comparison with those of oil shale by using Rock-Eval analysis demonstrated essential differences between peat and oil shale as pyrolysis feedstock. As a result of hydrocracking the total oil yield was increased more than twice compared with that of semicoking, 29.8 and 13%, respectively. Hydrocracking and semicoking led to significant deoxygenation of oil and solid residual conversion products via oxygen removal as carbon dioxide and water. Hydroxyl-, carboxyl-, carbonyl- and other oxygen functionalities in peat initial matter being hydrocracked and modified, the oil was characterized by elevated hydrocarbon content and decreased that of polar oxygen compounds. As the oxygen content of the product decreases, the energy content significantly increases and peat oil, particularly its hydrophobic fractions, can be used for synthetic liquid fuel.