Petroleum chemists urged to use TLC - C&EN Global Enterprise (ACS

First Page Image ... Martin suggests that industry in general and the petroleum industry in particular have been less than open about their experience...
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of the disposal problems can be handled efficiently, but the color problem is still a costly one. The color components are by-products of lignin oxidation and degradation. The most common decoloration process used at present, Dr. Kennedy says, is the "massive-lime" process, which flocculates the color components. A "mini-lime" variation also is used. A third process has been introduced recently in Sweden which employs ion exchange decoloration. All three processes, Dr. Kennedy claims, suffer from several drawbacks. One is that the final degree of decoloration is limited. Also, they require high capital and operating costs, and the large quantities of lime necessitate special handling techniques. In the new Rohm and Haas process, acidic bleach effluent is passed through a bed of the adsorbent that removes colorants and other organics. The adsorbent is periodically regenerated with a caustic process stream that removes the colorants and concentrates them for subsequent combustion in the mill's caustic recovery furnace. Because Amberlite XAD-8 is not an ion exchange resin, it will not remove chloride ions from the bleach effluent. Consequently, there is no danger of increasing the chloride level of the processing loop, a major problem in some processes. The new process is capable of treating all or part of the bleach effluent as long as it remains acidic. It can reduce color of the total bleach effluent by 90 to 95%. Concurrently, BOD can be reduced by up to 40% and the chemical oxygen demand can be reduced by up to 60%. Economic analysis of a test at a large pulp mill indicates that the new process is competitive with existing processes. A speculative cost comparison made by Dr. Kennedy suggests that the Rohm and Haas process can be operated at costs from 55 to 64 cents per ton of pulp. This compares with $1.86 for the massive-lime process, $1.26 for the mini-lime process, and 92 cents to $1.85 for the ion exchange process. Capital cost for an 800 ton-per-day plant providing 72% total bleach decoloration would be $710,000 to $920,000 for the new process. The corresponding cost for the massive-lime process would be $2.36 million, for the mini-lime process $900,000, and for the ion exchange process $1.8 million.

Federal panel reports on hydrogen FUEL—The possible ultimate depletion of fossil fuels has prompted numerous investigations into the potential of other sources of energy. The most comprehensive of these was begun in 1972 by the Energy R&D Goals Committee of the Federal Council on Science and Technology.

Panel indicates R&D goals for nonfossil fuel industry Short term (by 1985) • Development and demonstration of methanol from coal as an automotive fuel. • Development and demonstration of hydrogen produced from coal for use in the industrial sector both as a chemical and a fuel. • Development and demonstration of hydrogen as an energy storage medium for electric utilities use in supplying peak power demands. ·. Development and demonstration of the production of gaseous and liquid fuels from urban and agricultural waste products. Long term (after 1985) • Use of hydrogen as a transportation fuel, particularly for aircraft and specialized ground vehicles. • Hydrogen production investigations. • Long-distance transmission and bulk storage of hydrogen. • Public safety studies. The study involved 11 separate panels, each looking into one aspect of the national energy problem. The chairman of the panel on hydrogen and synthetic fuels, Dr. John W. Michel of Oak Ridge National Laboratory, has summarized the panel's findings and sketched its recommendations for research and development. The panel's main conclusion was that synthetic fuels, particularly hydrogen, can have a significant and beneficial effect over the long term. The main obstacles to use of hydrogen as a universal fuel are high cost relative to present fuels and unresolved problems of handling a low-density or cryogenic fluid. The panel believes that safety considerations will present no serious obstacle to use of hydrogen. According to Dr. Michel, the panel had no doubt that most of the economic problems can be resolved by appropriate R&D programs. The recommendations of the panel were divided into two categories, those that could have major impact on the nation before 1985 and those after 1985. Assuming a reasonable funding level, the panel projects that its programs would require up to five years of effort in most cases. What constitutes a reasonable funding level has not been made public at this time. A methanol R&D program would establish the economics and technology of methanol production from coal and lignite, as well as the end uses in automobiles. Because auto transport represents the biggest single use of petroleum, successful implementation of the program could have significant effects on oil imports and on air pollution. Several hydrogen utilization programs also appear to have near-term viability and would relieve the demand for natu-

ral gas and petroleum. The panel estimates that a five- to 10-year R&D program would be required to establish the feasibility of using hydrogen as a transportation fuel. This program would place particular emphasis on fuel tankage and logistics and their intarrelationships with engine and frame considerations. Hydrogen production investigations to improve water electrolysis processes, as well as investigation of new methods such as thermochemical processes (C&EN, Sept. 3, page 32), could also involve five- to 10-year programs. Longdistance transmission and bulk storage of hydrogen, including system studies, design limitations, and component development likely would require continuing effort for at least five years. The panel sees public safety and overall system analysis as long-term, lowlevel efforts. However, these efforts are essential to a smooth implementation period and to coordination of the various programs.

Petroleum chemists urged to use TLC PETROLEUM—"It is time for all petroleum chemists to take a more serious look at the quantitative potential of thin-layer chromatography (TLC) for the separation and direct quantitation of heavy hydrocarbon types in air, water, soil, rocks, crude oils, and refined oils as well as their various additives and derivatives." This invitation to participate in a renaissance of TLC was extended by Dr. Theodore T. Martin, of Continental Oil Co., after reviewing recent literature. Without pressing an indictment, Dr. Martin suggests that industry in general and the petroleum industry in particular have been less than open about their experience with TLC. Although he admits that many industrial applications of TLC are proprietary, he emphasizes that TLC is a practical approach to the development of fast, quantitative analytical methods. To some extent Dr. Martin is attempting to revitalize the "crusade" for TLC begun in 1966 by F. C. A. Killer and R. Amos. According to Dr. Martin, Killer and Amos published a formidable package of TLC procedures for separation and identification of petroleum and petroleum products and additives. For unexplained reasons, the 1966 crusade didn't generate much overt enthusiasm, a fact that still puzzles Dr. Martin. One application of TLC from Dr. Martin's new viewpoint is the determination of total diols in fatty alcohols. He says that this procedure is primarily intended for the analysis of C-12 through C-20 alcohols as well as for mixtures of any or all of them. Only slight modifications are required to extend the analytical range to include all alcohols from C-8 through C-24. Sept. 10, 1973 C&EN 19

Another application is the separation and identification of alkene and hydroxy alkane sulfonates. The procedure can also be extended to include unhydrolyzed sultones. Where routine analyses of many samples are involved, Dr. Martin claims that less than 15 minutes per sample is required. In a well-equipped laboratory, complete automation of the TLC instrumentation and data handling operations is not difficult and can be used to further de-

crease the manpower requirements without any great loss in precision, he says. Despite the slow outward acceptance of TLC, Dr. Martin believes that at last the petroleum industry is ready to recognize the worth of the technique and, it is hoped, is ready to allow the publication of more information on heretofore proprietary experience. Perhaps this second invitation will bring a greater response.

New instruments shown at exposition Scientific instruments on view at the National Chemical Exposition, held late last month in Chicago in conjunction with the national meeting of the American Chemical Society, included a new line of gas chromatographs, a new NMR spectrometer, and a Fourier transform accessory for routine NMR spectrometry. However, honors for novelty went to an automated system for thinlayer chromatography. Carle Instruments, Inc., Fullerton, Calif., introduced its AGC line of analytical gas chromatographs. According to Carle, the new models are the result of "a fresh approach" to the problems of gas chromatography that achieves high levels of quantitative accuracy at a relatively modest price. This accuracy is obtained, Carle says, by providing almost absolute temperature stability—a full-proportional isothermal temperature controller is capable of sensing changes as small as 0.01° C. High thermal stability also provides the repeat retention times so crucial for accurate quantitative analysis, Carle says, noting that day-to-day repeatability is better than 0.2% of set temperature under normal laboratory conditions. The firm currently offers three models: AGC-111, with filament and thermistor detectors, at $1750; AGC-211, with a flame ionization detector rated at better than 2.5 X 10~ 12 gram of hydrocarbons per second, at

$2030; and AGC-311, with both thermal conductivity and flame ionization detectors, at $2675. Perkin-Elmer Corp., Norwalk, Conn., showed its new Model R32 90-MHz.

Perkin-Elmer spectrometer exhibit draws interest of several chemists

Exposition attendees examine Regis Chemical's automated TLC equipment

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C&EN Sept. 10, 1973

NMR spectrometer, said to be the first commercially available high-field permanent magnet NMR instrument. P-E says the Model R32, with such features as spin decoupling and variable temperature system, compares favorably with the research instruments of two or three years ago, yet sells for only $36,600. The Model TT-7 pulsed-Fourier transform system for nuclear magnetic resonance spectrometry was unveiled by Transform Technology, Inc., Mountain view, Calif. The firm says the TT-7 will bring to "routine" NMR spectrometry the benefits of FT operation—greater sample throughput, rapid visual display of spectra, better quantitative measurements, and improved signal-to-noise performance—and will free expensive research instruments

for more demanding applications. The TT-7 system, including RF circuitry, control/display unit, keyboard, and dedicated minicomputer, is priced at $20,600, ready for use with the Varian T60A. Systems for other NMR instruments will be available later. Regis Chemical Co., Morton Grove, 111., introduced its programed multiple development (PMD) system for thinlayer chromatography (C&EN, Aug. 13, page 14). Regis boasts that the automated technique can provide resolution and sensitivity unprecedented for TLC; alternatively, it can drastically reduce the time required for routine separations. The Model 2000 programer unit sells for $4800. A two-day PDM workshop at Regis laboratories is included in that price. Model 222 developer units cost $800 each. One programer can control several developer units.