GB197353A - Process & apparatus for fractional separation of vapours and gases - Google Patents

Abstract

197,353. Plauson's (Parent Co.), Ltd., (Plauson, H.). Dec. 7, 1921. Gases, separating mixtures of; diffusion apparatus for gases.- Vapours or gases are separated by selective passage through a porous diaphragm in an apparatus in which a difference of electric potential (about 20-100 volts) is maintained between the diaphragm and the vapours or gases by applying an electric charge either to the diaphragm or to the gases. The diaphragm may have fairly large pores and may be formed of loose powdered rnaterial such as sand, glass, carbon, graphite, carborundum, metal, china clay, silicic acid, cement, chalk, gypsum, feldspar &c. or of these materials treated to form a rigid diaphragm by addition of a binding agent, or 'by ignition, chemical decomposition, &c., or of superimposed slotted or corrugated metal plates; or wire netting between which porous material may be placed. Vapours generated by heating a liquid in the lower part 2, Fig. 1, of a still rise into contact with a porous diaphragm 3 clamped by insulated connections 5, 6 between the lower part 2 and the upper part 1. A perforated electrode 7 is arranged below the diaphragm and connected to the part 2. Electrical connections 15, 16 are made with the parts 1, 2. A diaphragm in the form of a number of connected porous cylinders and an electrode having arms-projecting into the cylinders may be used. Two diaphragms may be placed in series, and may be formed of loose material resting on-perforated plates in electrical connection with the parts of the still. The diaphragm may be cleaned during use by removing impurities which settle on its surface, as, for example, during the distillation of oils containing wax, naphthalene, anthracene, asphalt, &c. either by forming the diaphragm as a hollow rotary cylinder, against which a scraping knife or rotary cleaning brush is held, or as a hollow fixed cylinder containing a rotating cleaning-worm. The vapours generated in the still 2, Fig. 14, pass into the space between two diaphragms 3, 3<a>, one of which is charged positively and the other negatively, and the vapours which pass through each diaphragm are removed by separate, outlets 12, 12<a>. The apparatus may be used for the distillation of two liquids having about the same boiling- points but of different polarities. According to the Provisional Specification, the diaphragm may also be made of blood-charcoal or kieselguhr.