An Easily Constructed Collector for Gas Chromatography
several modifications, the apparatus described below was constructed.
The collector is made from 0.049-in. aluminum sheet which is easily bent in a vise using wooden blocks to avoid marring the metal and t o keep the bends straight. The hinges used are those ordinarily available a t any hardware store and from which the pin has been removed. The central two hinge portions are bolted to the movable holder while the end portions are bolted to the stationary bracket. This allows both a lateral and a hinging motion of the movable collector. A small spring is inserted onto the hinge.pin between thetwo central hinge portions to maintain pressure on the collecting tubes a t the collector port. The stationary bracket is fastened to the side of the gas chromatograph using the two lower screws which hold the collector plate to the frame. We used a Varian Aerograph Model A90-P but this design should be adaptable to most other instruments. The glass collectors are constructed by standard glassblowing techniques and the various dimensions (see diagram) may he altered as needed. We used 7-mm ad glass tubing. Once the apparatus is fastened in place, one can select any of the five collecting tubes by pulling back on the movable portion of the collector, sliding it laterally and positioning the desired collecting tube a t the collector port. The spring holds the tube a t the collector port and prevents leakage so that the gases pass through the tube. This apparatus is simple and very inexpensive to construct and, because of its simplicity, offers trouble-free operation. Current Address: Owens Corning Fiberglass, Technical Center, Granville, Ohio 43023 Current Address: Goodyear Tire & Rubber Co., Research Division, Akron, Ohio 44316. University of Michigan Ann Arbor, 48109
J. Richard Tolerl Howard S. Friedman2
Volume 55, Number 6, June 1978 / 375