A Fractional Collector from Junk A research project a t Shippenshurg State College involved the separation of four ions fmm a mixture. To do this separation a resin column was used and a flow rate established to collect one 50-ml sample every hour. In order to accomplish the proper separation, samples had to be taken during both daytime and nighttime hours. At this time a factog-produced, fractional collector was economically impossible for the college; therefore, a cheap model had to he made. To make such an instrument, materials including en old bicycle wheel, an electric wall clock, a constant speed motor, a small variable speed control, and a miemswitch were connected together. The total price of this instrument when completed turned out to he just under ten dollars. The complete instrument collected twenty 50-ml samples before it had to he reset for another run. The first step of construction included mounting the bicycle wheel in a horizontal position to act as a revolving table. A circular table was placed on the wheel spokes, and 50-ml heakers were then placed on the table against the rim of the wheel. The separating column was positioned above the wheel so the beakers would pass directly below its tip. Secondly, the constant speed matar was positioned so it was in constant contact with the lower wheel rim; therefare, the wheel could not turn without the motor running. In turn, the motor was connected to the variable speed control which was then connected to the microswitch, which controlled the electricity flow. The microswitch was mounted on the face of the wall clock. It was positioned in such a manner that the minute hand of the clock would hit the switch. The clock hand turned on the switch once every hour for approximately 15 see. Therefore, the motor could turn for 15 see a t the speed which was set hy the variable speed control. Every hour, one 50-ml beaker will turn under the column and he replaced by an empty beaker the neat hour.
Shippenshurg State College Shippensburg, Pennsylvania 17257
Volume 51, Number 8, August 1974
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