EFFICIENT ABSORPTION TRAP FOR NOXIOUS GASES IRVING ALLANj KAYE, LOUIS SATTLER, and ROGER TWEED Brooklyn College, Brooklyn, New York
38 mm. a d
T H E trap shown in Figure 1 is readily constructed from available laboratory materials, is efficient in taking care of rapid surges of gas, and has a safety feature which prevents the backing-up of water into the reaction vessel when the flow of water is interrupted.' Figure 2 is an all-glass version of the apparatus. In use the exit waters from the condenser enter the trap a t A and leave a t D, thus forming a moving pool of water in which the water-soluble gases are trapped and a t the same time creating a gentle vacuum. The
' For other designs of gas traps see FIESER,L. F., "Experiments in Oreanic Chemistrv." D. C. Heath and Co.. New York. 1941, pp. 54, 313; and S~TIILER, L.,Chemist ~lz&sl, 35, 7 i (1946).
noxious gas coming from the top of the condenser enters a t B. The bend of C , sealed off with a drop or two of water, acts as a safety valve. The ends of A and B, outside the side-arm test tube, are best shaped, like C, in the form of U-bends. When A and C are sealed off with pieces of rubber and Hofmann screw clamps, the apparatus may be used as a steam trap, the steam entering a t D and leaving a t B. The water, collecting a t the bottom of t,he apparatus, is removed continuously through A by opening its clamp just wide enough to pennit escape of the water.