More Plates in One Chromatographic Tank Jamil Anwar Institute of Chemistry, University of the Punjab, Lahore-54590 Pakistan capacity of development tank but also significantly saved Rectangular glass tanks, varying in thickness and size, the developing solvent and laboratory space. Use of a are commonly used a s development chambers for ascendsmaller quantity of the solvent also caused fewer problems ing thin-layer chromatography. The plates in these tanks with respect to pollution and ventilation. usually are placed in a slightly inclined position with the lower end dipping into the solvent and upper end along the tank wall. If the plates are placed side by side, a tank of 4 x 10 x 12 in. can accommodate only three plates of 3 x 8 in. We faced the problem in placing 36 plates of our firstyear analytical chemistry class (one plate of each student). At least 12 development tanks were required to accommodate the 36 plates. I n addition to that a large volume of solvent also was needed for the development. We solved the problem by modifying only four tanks. I n our local workshop, we prepared 2.5- x 10in. plastic strips of 0.3-in. thickness and grooved them as shown in Figure 1. Then two strips were glued in a development t a n k i n such a way that their grooves were exactly facing each other, a s shown in Figure 2. Nine plates could be placed a t a t i m e i n one t a n k equipped with grooved strips. This Figure 2. The modifiedtank. modification not only increased the Figure 1. Plastic inserts fortank modification.
1136
Journal of Chemical Education
