The influence of the addition of expired pharmaceuticals (EP) along with coal tar pitch (CTP) in the amount of 2% each on the pyrolysis process of three coals of different rank was investigated using the method of X-raying of the heated charge, the thermogravimetric method (TG), and the Scanning Electron Microscopy (SEM). The mass loss of the coals under study was observed during their pyrolysis and co-pyrolysis at different stages of the coking process. The changes in volume of the coals with and without additives were determined on the basis of analysis of X-ray films of the heated charge. It was stated that the increase in plasticity range during co-pyrolysis of the coals with EP additive and the restrained increase in charge volume at the stage of swollen grains take place and can lead to decrease in coking pressure. The addition of EP to the coals of medium and high rank contributes to the formation of a more compacted co-pyrolysate in comparison to the pyrolysate of single coal. A possible mechanism of interaction of the CTP and EP additives with the organic matter of coals was discussed. (C) 2013 Elsevier Ltd. All rights reserved.