GB170645A - Improved treatment of wool to prepare it for manufacture - Google Patents

Abstract

170,645. Coghlan, Sir T. A. July 21, 1920. Wool fat, extracting by solvents. Wool is cleaned by first treating it at a temperature of 45‹ C. or below with trichlorethylene, and then removing the residual trichlorethylene by a current of carbon dioxide, which may be bubbled through oil and then used again, or by washing with water at about 45‹ C., the water being subsequently treated for recovery of potash salts. The wool may finally be washed with cold water, dried, and carbonized, as usual, by means of sulphuric acid. Apparatus for treating the wool with trichlorethylene may be used, wherein the wool charged into a cage is placed in a vessel having an hermetic closure and a lift-away or hinged cover, air being first pumped from the vessel, after which trichlorethylene is introduced and heated by steam coils to 45‹ C.; or the wool may be first treated with the solvent that is almost saturated, then with less saturated solvent, and so on, a final treatment with fresh trichlorethylene being given. Apparatus is also described, wherein a series of connected vessels 1 - - 4 are used, each communicating by pipes with a storage tank f, an exhaust tank or still n, and a vacuum pump p. Each vessel can receive fresh wool, be evacuated, and be supplied with fresh trichlorethylene, in any order, whilst trichlorethylene, after acting in one vessel, can be moved to another vessel under the pressure of its own vapour, valves d, b<1> - - b<4> being operated for these purposes. The vacuum pump p also serves for distilling the spent solvent containing dissolved wool grease in the still n through a distillation column r and condenser s into a receiver t, whence the trichlorethylene is raised by a pump u to the storage-tank f. The wool cages run on rails near the vessels 1 - - 4. It is stated that contact with lead and greasy fabric is avoided in the apparatus used. Commercial trichlorethylene of boiling point 90‹ C. may be employed.