Report for Analytical Chemists
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««per? If you are, stop. S&S has already done the job for you. They are called #560 folded analytical filter papers, and they're tear-proof. Used for preparing Glucose, BUN or other protein-free filtrations, #560 folded cost only $1.83 per box of 100, 12Vz cm diameter. Minimum order is $5.00. #560 folded filter papers is just one more lab aid from S&S, manufacturers of: 1 Pure cellulose acetate for electrophoresis. 2 Collodion Bags for protein concentration. 3 Standard S&S 903 Paper for PKU tests. 4 Finest Filter Papers, Chromatography Papers. 5 Folded Filter Papers. the first name in filtration...
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ANALYTICAL CHEMISTRY
cedural and technological problems which must be overcome to make these processes economically feasible are basically scaled-up versions of the same kinds of problems of identification, separation, and concentration which are continually met and overcome by the analytical chemist. For example, uranium exists in sea water to the extent of about 0.003 part per million. A process has been developed for extracting this uranium by means of ion exchange in combination with tidal currents to cause the water to pass through the resin bed. Even though about 100 tons of sea water are required to yield one cent's worth of uranium, it is not unreasonable to predict that this may become an economically feasible means of meeting a significant fraction of the world's demand for this metal. I t is probable that other metals can similarly be extracted commercially on an economic basis by use of other highly selective resins in the not-too-distant future. It is also interesting to note at this point that the possibilities of using tidal currents as sources of power are receiving continuing attention; however, technology is likely as advanced as far as is economically warranted at the present time. Natural Enrichment of Dissolved Components
Some marine organisms serve to collect and to concentrate some of the trace components of ocean water. As examples, iodine is concentrated by sponges and seaweeds, iron by some sea snails, copper and zinc by some mollusks, and nickel by sponges and mollusks. It is highly possible that, if more basic knowledge could be gained as to the mechanisms by which these concentrating actions occur, the processes could be deliberately exploited in meaningful ways. Within the last five years, three "hot brine pools" have been discovered deep in the center of the Red Sea. Numerous technical and popularized articles have appeared describing these regions of enriched concentrations of dissolved components (8). The largest of these pools, named the Atlantis, is at a depth of almost 2,000 meters, has a thickness of about 180 meters, extends over an area of about 8 miles
by 4 miles, is at a temperature of about 45 ° C , is about ten times more concentrated than normal sea waters in sodium, potassium, chlorine, and calcium, and contains some trace elements at concentrations ranging up to 50,000 times those found in average ocean waters. Among the analytical tools which played very extensive roles in the identification and characterization of these hot brine pools were atomic absorption spectroscopy and the electrobalance, the latter being particularly usable for quantitative weighings under shipboard conditions. Sediments, which were collected from the ocean floor in the regions of these pools by dredging and by coring, are gel-like, which fact suggests that they were formed by precipitation. Analyses of these sediments, after drying, reveals the presence of iron, zinc, manganese, cobalt, cadmium, barium, and copper, mostly as oxides, in concentrations and quantities that are of commercial interest. Another type of analytical determination which has proved to be useful in marine science, including the analyses of the Red Sea hot brine pools, is the determination of 18 0. In general, ocean waters are somewhat enriched in 1 8 0 as compared to fresh waters, and highly saline waters are even more highly enriched in 1 8 0. However, the 1 8 0 content of the Red Sea brines is even less than that of average sea water. This observation, along with several others, has led to the tentative explanation that these pools originated by discharge from the ocean floor. Possibly there is a rifting of rock in the ocean floor, with water going down and then returning back up, leaching the minerals as it goes. If this explanation is correct, these pools actually comprise continuous sources of salts and of heat. The economic potential of these pools is tremendous. One of the resources being extracted from sea water on a commercial basis is pure water. The amounts being extracted have increased about 30% per year for each of the past ten years (7). The processes are of practical and potential interest, not only because of the pure water produced, but also
