with an additional 30 gas-to-oil conver sions that may take place in the same period, the prospect is that oil will power the majority of electric power plants for the first time in history. Gas and oil together could possibly furnish primary heat for two thirds of the electrical power stations. How much of the gas would be SNG is moot, but there is little doubt that petroleum's position in the nonautomotive fuel busi ness would be greatly enhanced, at least in the near term. One problem that petroleum com panies would face is planning and analy sis of current operations to meet the de mands of the power companies. To help solve the problem M. W. Kellogg is stepping up its involvement in comput erized planning and analysis. Dr. Richard H. Kantor, a process engineer at Kellogg's Houston office, notes that marginal fuel gas supplied to a pipeline as well as low-sulfur fuel oil are enjoying market prices far above the levels of five years ago. This has caused engineering and construction com panies such as Kellogg to polish up their analytical tools for the new direction in operations. Recent developments in linear pro graming have allowed Kellogg to ad vance its planning capabilities. Describ ing the company's activities at a sym posium on process evaluation—predesign and economic analysis, held by the Division of Industrial and Engineering Chemistry, Dr. Kantor notes that Kellogg has acquired a programing sys tem for automatic generation of stan dardized, logical matrices and reports. Classified by major process activity, the resulting models have linear programing formulation techniques in common, but all data and premises for a specific application are supplied independently as needed. There are no data built into the basic program. The overall planning and analysis capacity at Kellogg is referred to as KELPLANS, and currently includes the use of operational linear program modeling in five major process activi ties. The newest addition to the KELPLANS system is the fuels refinery complex. The process configuration represented by the current fuels refinery reflects the trend toward conversion of refinery feed stocks, probably imported high-sulfur crudes, into low-sulfur fuel oils and SNG. Based on product demands and economics, the product slate may range from some ratio of SNG:fuel oil to essentially complete conversion of the crude to SNG. Exclusion of motor fuels from the product slate may allow access to lowerpriced imported feedstocks, since prod ucts with a heat or power end use are less likely to come under restrictive con trols. A separate modeling system for handling cases of this type allows the removal of large sections of the con ventional refinery model pertaining to processing and specification blending of
motor fuels. This results in reducing the computer time for compiling and optimizing the linear program. In developing a fuels refinery model with a capability of producing SNG, Dr. Kantor and his associates neces sarily considered streams that may be insignificant or even nonexistent in con ventional refinery studies. Chemical process water, oxygen for partial com bustion, and carbon dioxide have little effect in the economics of the conven tional refinery but are important in the SNG/fuels refinery.
Hepatitis antigen removed from plasma l&EC—Even if blood donors were routinely screened for hepatitis antigen, users of plasma products would still be subject to considerable risk of infection. Now a process that can effi ciently and economically remove anti gen from plasma on a large scale has been developed by chemical engineer Stanley E. Charm and Bing L. Wong of the New England Enzyme Center of Tufts University's school of medicine. An outgrowth of enzyme isolation techniques, the process uses bound hepatitis antibody to form a complex with the antigen in plasma. The com plex can then be filtered and bound antibody regenerated and reused. Serum hepatitis is frequently associ ated with a particle called Australia antigen or hepatitis-associated antigen. It is strongly suspected of causing the disease either by itself or as part of the infectious agent (C&EN, Aug. 14, page 24). After blood from donors has passed its short "shelf-life" as whole blood, blood cells are removed and the plasma pooled for processing into plasma prod ucts such as fibrinogen and other clot ting factors used to control bleeding during and after surgery. The incidence of hepatitis in the general population, Dr. Charm points out, is about one in 1000. Thus, he notes, plasma products have a very high incidence of hepatitis associated with them. The new process uses sepharose 2B to which hepatitis antibody from goats has been attached by a cyanogen bro mide method—about 20 mg. of antibody to 1 ml. of sepharose. Plasma and anti body are mixed gently at 8° C. for sev eral hours. The complex formed is removed by filtration of the plasma through filter paper. Treating the complex by washing with an alkaline (pH 11) saline solution dissociates antigen, which, as a by-prod uct, can be used to produce more anti body in animals. Bound antibody is regenerated by washing with a pH 7 saline solution. It can then be reused. Dr. Charm thinks that first commer cial use of the new process would most logically be made by large companies
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Water determinations In the field and in the lab with one precision L/l aquametry apparatus. L/I's instrument is so simple that untrained personnel can make a deter mination in 2 minutes with high precision. L/l guarantees 1 % accuracy,0.5% repro ducibility over 90% of the range of the instrument (1 part/million to 100% water). L/I's price is $355 complete with one quart of K-F reagent, which is $700 less than comparable instruments. L/I's 6" χ 10" apparatus uses your Karl Fischer reagent bottle as a reservoir, eliminating the odors and hazards of transfer. The reaction vessel is an ordi nary 4 oz. disposable "cream" jar. Using L/I's microreaction vessel —interchange able with the 4 oz. jar—3 nanoliters of water can be measured in 2 ml. Save time in standardizing your K-F titer with a GRUNBAUM K-F Pipet (repro ducibility 0 . 1 % . Price $12.00). Use the same pipet for sampling. For more details, fill in and return the coupon. Gentlemen: Send me details on your Aquametry Apparatus. Name Title Organization Street
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making plasma products, since they could best carry out the clinical testing that would be required. The Tufts engineers have so far carried out work only on bench scale but plan pilot plant development. Complexing rate between antibody and antigen, Dr. Charm says, varies with the ratio of plasma to bound antibody, reaching a maximum at ratios of less than 4 ml. of plasma to 10 mg. antibody bound to 1 ml. of sepharose. The rate also increases with temperature. Dr. Charm prefers to operate at a low 8° C , to prevent bacterial contamination. At this temperature and with the mixing conditions used (magnetic stirring), two hours are required for a 90% (one log cycle) reduction in antigen concentration. The process time required to reduce antigen to a safe level depends on the size of the plasma pool. Thus, Dr. Charm estimates, at 8° C. 32 hours would be required for a 100,000-ml. pool, 26 hours for 100 ml. The key to economic feasibility, Dr. Charm says, lies in the ability to reuse bound antibody. So far, the Tufts engineers have regenerated and reused bound antibody 25 times without any indication of the limit. Antibody, Dr. Charm says, cost about $10 per 100 mg., and a 10-liter plasma pool would require some 25,000 mg. Thus, he estimates, if antibody can be used 100 times, processing costs should run about $2.00 to $4.00 per liter of plasma.
Methods measure S0 2 in atmosphere
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WATER, AIR, AND WASTE—Airborne particles play an important role in the transport of sulfur dioxide and presumably other noxious gases over long distances. They could present a serious health hazard because particles in the size range of 7 microns down to 0.01 micron can pass into the lower reaches of the respiratory tract and lodge there, notes Dr. Cyrill Brosset, research director at the Swedish Water and Air Pollution Research Laboratory in Gothenburg, and professor of Chemistry at neighboring Chalmers University of Technology. Moreover, there is now a sizable body of evidence to suggest that sulfur-laden particles, swept by winds northward from the industrial centers of Europe and the U.K., contribute to the increasing acidification of lakes and rivers throughout Scandinavia. From studies that he and his associates have made during the past several years, Dr. Brosset concludes that the intimate association of sulfur and its oxides with particulates is an important aspect of the overall environmental health picture. He theorizes that atoms of iron, nickel, chromium and the like within the particles well may catalyze the oxidation of sulfur dioxide adhering
to them to sulfur trioxide which is then rapidly converted to sulfuric acid. The sulfuric acid-bearing particles may be inhaled. And they are washed out of the atmosphere by rain and snow, ultimately entering the river system and lakes, thereby increasing their acidity level. Much of Dr. Brosset's efforts have been directed toward devising improved techniques for accurately measuring p.article-borne sulfur oxides and strong acids. In one set of experiments, he uses x-ray fluorescence to check the amount of sulfur associated with the particles as well as the free SO2 content of the air. Air, sucked through a probe at a preselected rate, passes first to a Teflon filter which traps the particles, and then through an alkali-resistant nylon filter impregnated with potassium bicarbonate which collects the SO2. Both filters are removed and placed separately in an x-ray fluorescence spectrometer to measure the sulfur content. Dr. Brosset points to a number of advantages to this system. For one, it is extremely sensitive and accurate. It is possible, for example, to measure SO2 at concentrations of less than 1 microgram per cubic meter of air, he claims. Too, the analysis is simple and rapid and doesn't depend on chemical reagents. Moreover, sampling stations may be set up at different geographical regions and the filters sent periodically to a central laboratory for measurement by trained technicians. "Its seems vital," Dr. Brosset says, "that accurate measurements are made of strong acid in respirable particles as well as of SO2 in the gas phase in parallel with epidemiological studies." He would like to see atmospheric readings of the type he is taking, conducted in such densely populated centers as London, New York, and Tokyo, which are often prone to severe air pollution events and where facilities are already available for compiling detailed statistical health records. In a related set of experiments, Dr. Brosset and his coworker, Dr. Christer Askne at Chalmers University, have deBrosset: possible health hazard
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