quiring removal of impurities, so other methods may be better. Whatever way the reduction is carried out in the AARC process, manganese metal is returned for reaction with aluminum trichloride. Capital costs for a plant to make 1000 tons per day of aluminum could be reduced to 35 to 60% of the cost for a new Bayer-Hall process plant of the same capacity, according to Mr. Toth. Actual capital costs might range from $500 to $850 per annual ton of aluminum. A modern Bayer-Hall plant of similar capacity would cost about $1400 per annual ton. Operating costs also could be less than those of the Bayer-Hall process by 20 to 45%, says Mr. Toth. For a 1000 ton-per-day plant, operating costs could range from 10 to 14 cents a pound, compared to about 18 cents a pound for an efficient Bayer-Hall process plant. The range in estimates of capital and operating costs for the Toth process results from including the economic effects of the several routes being investigated for its four steps, explains Alfred Lippman, AARC's senior vice president and director of research. This contrasts with the long-researched Bayer-Hall process and other electrolytic methods with relatively limited flexibility, he adds. Work on improving the Toth process is under way at AARC's facilities leased from Gulf South Research Institute in New Orleans. Correlative research is being performed by independent research laboratories. At this time, says Mr. Toth, AARC is raising $2 million to fund further research and the design of a pilot plant, which is scheduled to begin operation in mid-1974. Details of research and development work at AARC are not being disclosed by Mr. Toth and Mr. Lippman except under secrecy agreements to protect new developments. Battelle's Columbus Laboratories has conducted a preliminary study of the Toth process and reports that expeditious R&D would be justified in view of the technical and economic potential of the process. AARC has concentrated on aluminum production rather than on use of byproducts. But the titanium and aluminum in Georgia kaolin occur in almost the same ratio as current demands for these metals. So the Toth process might seemingly supply both- And the fine white silica residue from clay chlorination might find many attractive applications. Furthermore, the Toth process might have the advantages of lower capital and production costs and the use of domestic ores, and, at the same time, not worsen the already severe strains on domestic electric power. The present adverse situation in U.S. balance of payments could be partly relieved by not having to import bauxite, alumina, and aluminum metal from countries with bauxite or low-cost power. 12 C&EN Feb. 26, 1973
ICI sees wide use for new Monflor line The family of fluorinated hydrocarbons that Imperial Chemical Industries' Mond division in England has developed (C&EN, Feb. 5, page 12), should result in the emergence of a wide range of unusual surface-active preparations. Typical possible products include improved formulations for mold-release agents, polishes, and antimist and rinsing solutions. The new hydrocarbons should also be useful in technical and research applications. Unlike other fluorinated hydrocarbons, the new ones, which form the basis of Id's Monflor product line, have a highly branched structure. Substitution of a fluorine atom in the molecule by hydrophilic groups opens the way to an almost limitless range of derivatives. The new fluorocarbons result from polymerizing tetrafluoroethylene in the presence of fluoride ions. They are low-molecular-weight oligomers that ICFs Dr. Harold Fielding and his team at Mond's new ventures group make by autoclaving tetrafluoroethylene for several hours at about 100° C. and less than 150 p.s.i. The pentamer obtained is separated and recovered from the liquid mixture by distillation. This pentamer (perfluoro-4-ethyl3,4-dimethylhex-ds-2-ene) contains a highly active vinylic fluorine atom that can be readily replaced by other groups. Aromatic substituents, for example, can then undergo the whole range of conventional reactions such as sulfonation and nitration. The Monflor product range contains both the strongly hydrophobic and oleophobic characteristics of the branched, fluorinated part of the molecule and
the hydrophilicity of the substituent groups. The cpmpounds reduce surface tension to 20 to 25 dynes per cm. In contrast, current hydrocarbon surface-active agents can't bring surface tension down much below 30 dynes per cm. Moreover, the fluorinated compounds are much more thermally and chemically stable than their hydrocarbon counterparts, Dr. Fielding notes. A typical use that Dr. Fielding cites for the compounds is pretreatment of molds used in making plastic parts. Conventional mold-release agents, he points out, tend to contaminate the plastic surfaces because of the relatively high concentrations required. Molded parts must then be cleaned before subsequent painting, metallizing, or assembly. But because the new fluorocarbons are so highly oleophobic, the low concentrations needed—as little as 0.1 to 0.2% by weight—make the degree of contamination negligible. Another potential outlet for the Monflor line is in formulating improved polishes for plastic floor and wall covering. Because these surfaces aren't easily wetted, the applied polish film tends to retract when it dries, leaving dry spots. Dr. Fielding claims that as little as 50 p.p.m. of one of the Monflor compounds in a polish formulation confers better wettability to it and improves leveling of the polish. Consequently, the surface can withstand many washings without deterioration of the polish film. Marked lowering of surface tension caused by the branched fluorinated hydrocarbons prevents surface formation of moisture droplets. Water flows off in a uniform, transparent film. The
Bubble covers construction A vinyl bubble rises over a construction site at Ashland Oil's refinery in Buffalo, N.Y., to help speed work on a plant to make substitute natural gas. Air forced between two layers of 12-mil-thick vinyl keeps the bubble structure rigid. The bubble will measure 264 feet long, 135 feet wide, and 40 feet high. Some 34,000 sq. ft. of space will be contained within the domelike structure.
ICI forms Monflor from tetrafluoroethylene
t. Tetrafluoroethylene
C F
zs
CF, \
Peril uoro-4-ethyl-3,4-dimethylh ex-c/s-2-ene
result, for example, is improved ap pearance of washed glass and silverware rinsed in formulations containing the compounds. The surface tension effect should also be an advantage in auto matic car washing operations. Dr. Fielding believes that the poten tial uses of the Monflor product line are far ranging. He foresees, for instance, their use as foaming agents for pipeline and oven cleaners, shampoos, and shav ing preparations. The improved mobili ty and stability they confer on foam might also lead to new flotation formu
lations for ore separation. There is also evidence of a synergistic effect on phenolic and other disinfectants. ICI is now launching Monflor sales in the U.K. and, through its Atlas divi sion, in western Europe. Price ranges from about $35 to $95 per kg. Although the price might appear high at first glance, it isn't the sole criterion that should be considered, Dr. Fielding points out. The new compounds' cost effectiveness as well as their unique effects should also be taken into ac count, he explains.
EDUCATION
Work-study program leads to Ph.D. Many schools have had undergraduate work-study programs in chemistry. And Northeastern University, Boston, is one ot them. Now, however, Northeastern has gone a step further and has created a work-study program in chemistry for the Ph.D. degree. Since last September, seven students in the program have been at the uni versity taking courses, as required in the program's first year. Chemistry professor B. C. Giessen, the program director, explains that the students will spend their second year working for co operating laboratories. Then they will return to Northeastern full time for thesis work. The program should not add more than six months to the time required for a traditional Ph.D., Dr. Giessen says. The idea of work-study programs for
the Ph.D. degree has gained some cur rency in chemistry circles. At the American Chemical Society's recent Eighth Biennial Education Conference (C&EN, Nov. 20, 1972, page 20), par ticipants supported a proposal that a feasibility study be carried out on the concept. The conferees felt that this type of program might add some needed breadth to Ph.D. education. In Northeastern's program, stu dents are selected from those college seniors who apply directly for admis sion to the program. Selection is based on grades and the ability to function effectively in industry. Final admission to the program comes at the end of the first year of study, when a review board will decide on the qualifications and fitness of the students to continue in the program.
Northeastern's Β. C. Giessen and Ph.D. work-study students David Levitt and Stephen Davis (from left) examine output of an x-ray ditfTactometer
Need any salt of petroleum sulfonate? Consider Witco as a volume supplier. Witco Chemical's Sonneborn Division has been producing and supplying more salts of petroleum sulfonate than anyone for many years. (We market them under the trade name Petronate*.) We manufacture the broadest range of top-quality oil and water soluble petroleum sulfonates in the world. Many specialized formu lations are also available. In addition, we often design new ones to overcome our customers' specific problems. Each of our salts of petroleum sulfonate is derived from carefully selected raw materials. Up-to-date processing techniques are used to provide the utmost in functionality, ease of handling and reliability. Of course, such customized manufacturing, as in the case of any salt of petroleum sulfonate, requires a volume order. So if you have a substantial need for any salts of petroleum sulfonate, consider the petroleum sulfonate pioneer... Witco Chemical.
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Feb. 26, 1973C&EN 13
