Wood Tar is a viscous, blackish brown liquid obtained as one of the products of the carbonization, or destructive distillation, of wood. It has an empyreumatic odor and sharp taste. The chief constituents are volatile terpene oils, neutral oils of high boiling point and high solvency, resin and fatty acids. The proportion of these vary in the different grades of tar, also according to tree species and the part of the tree used, type of carbonization oven. There are two types: hardwood tars, derived from such woods as oak and beech; and resinous tars, derived from pine wood, particularly from resinous stumps and roots. Fat wood tar made from stumps of the pine tree has always been recognized as the best tar, since it contains much of the ingredients which protect the living tree. However, stumps are hard to find and expensive, so ordinary pine wood is mostly used nowadays. Crude wood tar may be used as fuel or for preserving rope and wood and for caulking. The tar may be fractionated to yield creosote, oils, and pitch.
Hardwood tars are obtained from pyroligneous acid, either as a deposit from the acid or as a residue from the distillation of the acid. Crude pyroligneous acid is the condensed, volatile product of wood distillation. Resinous wood tars differ from hardwood tar in containing the pleasant-smelling mixture of terpenes known as turpentine. Pine-wood tar, commonly called Stockholm, or Archangel, tar, is made extensively in the forests of Russia, Sweden, and Finland. It is the residue after the turpentine has been distilled, usually with the aid of steam. It is widely used in manufacturing tarred ropes and twine and in impregnating hemp fiber for oakum. In pharmacy, it has some slight use as a component of some ointments and antiseptics. Distillates of pine-wood tar, particularly the creosote fraction, are used in metallurgy in the froth flotation processes.
Wood Vinegar Premium Organic Fertilizer