Improvements in the production of materials containing bitumen and tar or mixtures of different tars for roads and underground construction

摘要

Materials containing bitumen and tar or mixtures of different tars are treated, for use in road construction and for waterproofing underground and foundation structures, by treating the materials at temperatures up to 130 DEG C. with simultaneous passage of oxygen or air and in the presence of up to 3 per cent sulphuric acid by weight, with or without the addition of oxidizing agents such as persulphate, or perborate. The residues of the common distillation of different tars or the distillation of one or more tars with petroleum may be used as starting materials with or without small additions of fatty oils, resin soap or substances used as drying agents in the paint industry such as peroxides. In examples, mixtures of petroleum asphalt, shale tar, coal tar-pitch, and brown coal tar are specified.