Membrane Extends Life of Fuel Cells - Chemical & Engineering News

Nov 6, 2010 - He says that the life of polystyrene electrolyte membranes in fuel cells is ... were used in the fuel cells aboard the recent Gemini-5 s...
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be used to determine the percentage of sulfur. A system developed by Gerald Kainz, of the Analytical Institute (University of Vienna, Austria), bums an organic sample containing carbon14, sulfur-35, or hydrogen-3. The technique uses an inlet tube with two heated nozzles at its exit. The sample passes through the inlet tube's first nozzle where it vaporizes or pyrolizes. The volatile products are then carried by nitrogen through a heated, constricted nozzle and burned in an oxygen stream passing through the combustion tube. Residue is burned by passing oxygen through the inlet tube. The combustion products are absorbed in methanol and 2-aminoethànol (methanoltoluene for hydrogen-3), and the activity is measured in a liquid scintillation counter. A microchemiçal technique, injection enthalpimetry, has been developed for titration reactions that require an excess of titrant. Injection enthalpimetry, says Dr. Joseph Jordan of Penn State, involves a rapid injection of 20 microliters of the appropriate concentrated reagent and measurement of the temperature change as a temperature pulse. The heat evolved, he says, depends on the number of moles reacted and is thus proportionate to sample size. Sample Volume. An accessory for use on American Instrument Co.'s thermometric titrator (Titra-ThermoMat) uses direct-injection enthalpimetry. The accessory reduces the sample volume for analysis from 20 ml. to 1 to 2 ml. and the titrant volume from 1 ml. to 0.01 to 0.2 ml. Rounding out the new developments is. a time-flow titrimetry system, developed by Dr? Benjamin W. Grunbaum of the University of California, Berkeley. The titrator assembly consists of a constant-flow timer, a single-probe electrode, a digital read-out microburet with reagent reservoir, a pH meter and recorder, and a magnetic stirring unit. The buret can be motor-driven or operated manually and can be synchronized with the recorder chart-drive. The constant-flow titrator, Dr. Grunbaum says, is a modular unit and is part of a portable microanalytical laboratory called the Cosmolab (compact self-contained mobile laboratory). The Cosmolab can handle with its own battery-operated power supply almost all of the functions performed in a clinical laboratory.

Membrane Extends Life of Fuel Cells GE replaces polystyrene with fluorine-substituted polystyrene in hydrogen-oxygen fuel cells Replacement of polystyrene with fluorine-substituted polystyrene as the electrolyte membrane in hydrogen/ oxygen fuel cells extends the life of the fuel cells four- to fivefold. So says General Electric, which has just initiated a program, based on the longerlife fuel cells, to provide power sources for use on land and sea. It expects to be selling in limited market areas by the end of next year. Dr. Arthur M. Bueche, vice president of research and development at GE, says that, unlike polystyrene, fluorine-substituted polystyrene resists chemical oxidation. He says that the life of polystyrene electrolyte membranes in fuel cells is limited because they oxidize and degrade. But because the fluorine-substituted membranes don't oxidize, and, therefore, don't degrade, they have an expected life of between 6000 and 8000 hr., compared with 1500 hr. for polystyrene. Polystyrene membranes were used in the fuel cells aboard the recent Gemini-5 space flight. Commercial applications for the longer-life fuel cells are under development at GE's Lynn, Mass., laboratories. According to Roy S. Mushrush, manager of GE's direct-energy

conversion operation, fuel cells capable of producing about 12 watts of power will be the first to reach the commercial stage, which he feels will be by next year. Commenting on the uses for such fuel cells, Mr. Mushrush cites power for portable communications equipment and remote television cameras. GE also has a long-range development program under way. Mr. Mushrush says that the longer-life fuel cells might have marine applications, such as power for sonobuoys, for highpower underwater lights, and for electrically heated diving suits. He also foresees some possible consumer uses for the fuel cells. These include electric power for house trailers, for camping equipment, and for golf carts. Mr. Mushrush visualizes more elaborate uses for fuel cells in the future. For example, he says that they might be used for emergency power in homes during power failures due to storms. Also, he says that an electric automobile powered by fuel cells is not inconceivable. But, he adds, this is a long way off because the cost and size of fuel cells for this purpose must be reduced to compete with internal combustion engines.

TOUGH. Dr. Russell Hodgdon, of GE's fuel cell laboratory, demonstrates the toughness of the soUd-polymer eieetroiytey fluorine-substituted polystyrene, which the company uses in the new version of its hydrogen-oxygen fuel cell SEPT.

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WeVe got a diamine ur ethane curative with 5 times the pot-life of the one you're using now. Curalon L Curalon L is a revolutionary, new diamine curative for hard urethane polymers. It gives five times the pot-life of other diamine curatives, so polymer mixes stay pourable long after conventional diamine systems become viscous and unworkable. Curalon L is especially useful for applications demanding a very high hardness, such as impression rolls, bushings, bearings, shock and impact devices. You can even produce large castings and hard parts with high isocyanate (NCO) content polymers.

Our regular urethane curative is pretty good, too. Curalon M For solid tires, printing rolls, seals, gaskets, tank linings, heel lifts, encapsulations and scores of other applications, Curalon M is an effective, economical diamine curative. Curalon M balancesexcellenthandling features with good physical properties in the finished product. It supercools, offers good color, low melting point, workable pot-life and fast cure, and yields high tensile and tear strength as well as excellent modulus, elongation and other physicals. You can also use Curalon M as a curative for epoxy-urethane blends. For more information on Curalon L or Curalon M, just fill out the coupon below. Chemical Division

hjNlROYAU

Industrial Organic Chemicals U.S. Rubber Co.,Chemical Division Naugatuck, Conn. 06771

U.S. R U B B E R Please send complete information on CuralonL·D Curalon M D NAME

FIRM

ADDRESS

;

CITY

STATE

TM CURALON IS THE U.S. RUBBER TRADEMARK FOR ITS URETHANE CURATIVE.

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Dye Systems Measure Large Radiation Doses Recent advances in intense-beam radiation technology and the demands of many applications in this field have forced a search for better dosimetric techniques. Research at the National Bureau of Standards by William L. McLaughlin has demonstrated the potential of several dye systems for use in measuring intense radiation doses in «the range of 10 5 to 10 8 rad. The dyes, colorless derivatives of triphenylmethane dyes—such as stabilized forms of pararosaniline nitriles— were previously developed for ultraviolet imaging. They are colorless until exposed to intense radiation. Conventional dosimeters, such as ionization chambers, silver halide emulsions, and some liquid-chemical devices, are generally not suitable for monitoring radiation-field gradients on a microscopic scale, Mr. McLaughlin says. With conventional systems capable of measuring high-resolution dose distributions, energy dependence of the response can cause difficulties in getting accurate readings. In contrast, he says, the new dye systems are capable of high-resolution measurement gradients in a heterogeneous radiation field. The dye systems, according to Mr. McLaughlin, are especially suited to radiation processing industries as a simple indicator of radiation dose distribution on a microscopic scale. Other potential uses include x-ray micrography, detecting mixed radiation, and molecular biology studies. The dyes will be of particular value in situations where a radiation effect must be viewed from a distance.

BRIEFS An inert gas cooling system, which shortens rotational molding cycle time, reduces warp age, and improves product toughness, has been developed by U.S. Industrial Chemicals Co. The system, for which patents have been applied, introduces and vents inert gas and cooling media to and from the mold during heating and cooling cycles in rotational molding equipment. This system, USI says, should be particularly useful in applications where high heating temperatures are necessary, such as in molding automotive parts. With crystalline polymers, crystalline growth

rate depends on the cooling rate. Rapid cooling obtained with this method decreases crystalline content in the molded part thereby improving toughness, USI says.

Mica is now being produced in the western U.S. by a fatty acid flotation process developed by scientists of the U.S. Department of Interior's Bureau of Mines. The first commercial plant, located in Mariposa County, California, treats about 150 tons per day of mica-bearing schist. Until now, the only commercial source of mica in the U.S. has been mica-bearing permatite deposits, located in the East.

A 10,000 gal.-per-hour sewage treatment pilot plant will be built and operated under a $617,000 contract signed by the U.S. Department of the Interior's Office of Coal Research and Rand Development Corp., of Cleveland, Ohio. The system uses coal and a filtration-adsorption process developed under a previous contract with Rand. The process has demonstrated on a small scale its ability to remove sewage and industrial contaminants to a degree equivalent to conventional activated-sludge processes, OCR says.

A new method has been developed by Cahn Instrument Co. to upgrade existing differential thermal analysis (DTA) instruments to perform thermogravimetry (TGA) work. Previous practice in adding TGA capability to DTA systems has been to provide a separate furnace for TGA. The new system, using Cahn recording vacuum electrobalances, allows using the original DTA furnace. The TGA accessory for DTA instruments can weigh samples from 2.5 grams down to 50 micrograms, in vacuum or reactive atmospheres, and at temperatures of up to 1200° C , the Paramount, Calif., company says.

Exclusive leasing rights to a large hopper car, designed and built by Aeronco Mfg. Corp., have been obtained by North American Car Corp. The car, largely of aluminum construction, consists of four articulated units (C&EN, Aug. 23, page 46). E. C. R. Lasher, North American's president, considers the development of the car

as the beginning for a rail-based logistics system. He says the car is the ideal vehicle for use in integral train service.

A rocket motor containing about 4000 lb. of berylliumized, polybutadiene acrylic nitrile fuel was successfully test fired at Edwards Air Force Base in California. This motor is the first of a series designed and manufactured by Thiokol Chemical under the Air Force's $800,000 Project Adobe.

NEW CHEMICALS Polymeric flocculant, Primafloc C-7, for raw water clarification is now available from Rohm & Haas. The Philadelphia, Pa., firm says that it can be used in industrial and sanitary applications where suspended matter is to be removed from aqueous systems. The flocculant can be used as a prime coagulant in clarifying turbid waters without the addition of inorganic coagulants such as alum or ferric sulfate, R&H says. C 30

Any epoxy curative will give you one or two outstanding qualities. lonox gives you eight. 1 . Excellent electrical properties 2 . Excellent high-temperature properties 3 . Outstanding chemical performance

Biodegradable alkanolamides for use as intermediates and agents are offered by Ultra division of Witco Chemical Co., Inc. Specifications and solubility of the 10 di- and monosubstituted materials, trade-named Ultrapole, differ in varying degrees to meet a wide range of requirements, the Paterson, N.J., firm says. C 31

A highly soluble fermentation nutrient for use in large- and small-scale fermentation is available from Amber Laboratories, Inc. The Milwaukee, Wis., company says the nutrient, called Amber AMP Series 60, is a concentrated liquid meat peptone with a total nitrogen content of more than 9.5%. Containing 60% solids, the nutrient is convenient to pump and meter. It supports the growth of a wide variety of microorganisms, especially where some form of meat protein and clarity is needed. C 32

4 . Supercools 5 . Long pot-life 6 . Short cure 7 . Non skin-staining O. Low cost If Tonox sounds like the kind of epoxy curative you've been looking for, fill in the coupon. We'll send vou all the details Chemical Division

UNlROYAL U.S.RUBBER

Industrial Organic Chemicals U.S. Rubber Co., Chemical Division Naugatuck, Conn. 06771

Please send complete information on Tonox. NAME

Butylated hydroxytoluene (BHT) has been added to the line of rubber chemicals available from National Polychemicals, Inc. The Wilmington Mass., firm says that Wytox BHT is a nonstaining, nondiscoloring antioxi-

FIRM ADDRESS CITY

STATE

TM TONOX IS THE U.S. RUBBER TRADEMARK FOR ITS AROMATIC DIAMINE CURATIVE.

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C&EN

EQUIPMENT

PROGRESS REPORT

These items have all been mentioned editorially in C&EN in the past month. If you haven't already sent for information on them, just check the appropriate key numbers on the coupon on page 70, and C&EN's Readers' Information Service will forward yourjrequest to the manufacturer.

INSTRUMENTS AND CONTROLS . . Product

Portable oxygen analyzers

Company

Ε 60

Proportional temperature controller Ε 61 (Model 51) Micro gas cell Ε 62 Solution fraction collector

Ε 63

Leak detector (Ultraprobe) Flowmeter kit

Ε 64

Gas chromatograph inlet

Ε 66

Vacuum-fusion gas analyzer

Ε 67

Ε 65

(VH-8) Carbon analysis accessories

Ε 68

Carbon evaporation assembly

Ε 69

Amino acid analyzer

Ε 70

Analytic Systems Co. Pasadena, Calif. Athena Controls, Inc. Conshohocken, Pa. Carle Instruments, Inc. Anaheim, Calif. Carle Instruments, Inc. Anaheim, Calif. Eitel-McCullough, Inc. San Carlos, Calif. Fischer & Porter Co. Warminster, Pa. Hamilton Co. Whittier, Calif. Heraeus-Engelhard Vacuum, Inc. Monroeville, Pa. Laboratory Equipment Corp. St. Joseph, Mich. Mikros Division Varian Associates Portland, Ore. Phoenix Precision Instrument

Co. Thermal conductivity instrument

Ε 71

Amino acid analyzer (Model 120C)

Ε 72

Chlorine analyzer

Ε 73

Philadelphia, Pa. Thermo-Physics Corp. Cambridge, Mass. Spinco Division Beckman Instruments, Inc. Palo Alto, Calif. Wallace & Tiernan, Inc. Belleville, N.J.

Features

For monitoring controlled environments Accommodates a wide variety of sensors Enables any infrared spectrometer to be operated as a gas chromatograph de­ tector Used with gas chromatographs and in­ frared spectrometers For pinpointing leaks to within 0.01 in. For use in pilot plants and research lab­ oratories Eliminates band spreading To determine oxygen, nitrogen, and hy­ drogen content in metals and other materials For use with the Leco rapid automatic carbon analyzer For electron microscope sample prepara­ tion For automatic separation, identification, and measurement of amino acids For ceramics, plastics, metals, and composites For analysis of samples as small as 0.02 micromole For determining waste water

residual chlorine in

EQUIPMENT AND LABWARE . . . Computer trainer (Model 601) Flexible heating cloth

Ε 75

Temperature/humidity chamber

Ε 76

Lab jack

Ε 77

Power source (Series SP) Laboratory stoppers

Ε 78

Industrial furnaces (Dyna-Trol) Crystal puller furnaces

Ε 80 Ε 81

Gas purifier and dryer

Ε 82

Mass sorption spring balance

Ε 83

Microbalance

E 84

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Ε 79

Arkay International, Inc. Brooklyn, N.Y. Basic Carbon Sanborn, N.Y. Blue M Electric Co. Blue Island, III. Cenco Instruments Corp. Chicago, III. Deltron, Inc. Philadelphia, Pa. Easthampton Rubber Thread Co. Easthampton, Mass. L & L Mfg. Co. Upland, Mich. Navan Products, Inc. El Segundo, Calif. United States Dynamics Newton Highlands, Mass. Worden Quartz Products, Inc. Houston, Tex. Worden Quartz Products, Inc. Houston, Tex.

For teaching computer basics, program­ ing, and number theory For trace and spot area heating Obtains the humidity condition by using a vapor-pressure system For supporting beakers, heaters, and burners Provides large amounts of consistent power Designed to reduce inventory and cost of laboratory stoppers For use up to 2300° F. For growing semiconductor crystals For continuously removing oxygen and moisture For measurement of small weight changes For thermogravimetric work

dant for both natural and synthetic rubbers. The trisubstituted, sterically hindered phenol is effective in preventing breakdown of rubber on aging. It is particularly effective in light-colored stocks and in formulations intended for contact with paints and lacquers. A technical grade in flake or crystal form is available as is a food-grade crystal form. C 33

A precious metal catalyst with high resistance to poisoning is now being produced by the chemical division of Engelhard Industries, Inc. Since the catalyst, T393 5% platinum on carbon sulfided, is relatively inactive for hydrogénation of aromatic rings, ketones, nitriles, esters, and some other functional groups, it will often effect the selective hydrogénation of polyfunc-

tional compounds, the Newark, N.J., company says. C 34

Pilot-plant quantities of chromium, cobalt, manganese, and rhenium metal carbonyls are available from Strem Chemicals, Inc.,^Danvers, Mass. The diglyme-stabilized sodium salt of vanadium carbonyl is also available. Metal carbonyls are used as chemical intermediates, catalysts for organic syntheses, combustion inhibitors, and metal-plating media. C 35

Further information on keyed Chemical and Equipment items is readily available . . .

Use handy coupon on page 70

September 13, 1965

Use this handy self-mailer to obt3in further information or literature. Simply mark the items desired, fill out the information requested, clip the coupon, fold, staple, and mail.

Name: Company: Street: _Zone

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Your Title:YOUR FUNCTIONS (Maximum of 2, please.) ΑΠ Β Π CΠ DΠ ΕΠ F Π

Management Process Research & Development Product Research & Development Basic Research Plant Operations Engineering Design & Construction

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CLIP COUPON—Fold along this line—fasten (staple, tape, glue) MAIL Your Industry:

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nitrations with confidence instead of capital

Call Fisher That call will put at your almost instant disposal, resources that would be diffi­ cult, if not impossible, to match. Re­ sources like:

Readers' Information Service

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how to program

Κ ( ) Petroleum Réf., Asphalts, Lubricants L ( ) Rubber and Plastic Products M ( ) Independent Laboratories Ν ( ) Consultants 0 ( ) Primary Metal Industries Ρ ( ) Fabricated Metal Products Q ( ) Machinery and Equipment R ( ) Transportation Equipment S ( ) Instruments and Controls Τ ( ) Education

1. Know-how and Experience—Research­ ers, technicians, operators who have per­ formed hundreds of nitrations over 16 years - in the lab, in the pilot plant, but most of all in full-scale commercial equipment. Every type of nitration : sol­ ids, mixed acids, concentrated acid. First reaction steps, intermediate steps, com­ plete product manufacture. High and low temperature nitrations. 2. Service—Process development, process improvement, scale-up from lab to com­ mercial production. If you need a ni­ trated product produced fast, Fisher can have it delivered to you before most people can get off the drawing board. If you have a process, we will check it out, improve it if we can. Improvements be­ come your exclusive property. Building your own plant? Test your process in our equipment, make special observations, like corrosion studies, under actual plant conditions. 8. Specialized Equipment and Facilities —Basic process equipment, you can take for granted. If we don't have it ready to go for your nitration, our specialists can assemble the pieces in a matter of hours. Unique facilities i n c l u d e : scrubbing towers to take care of nitrous oxide fumes, an effluent treatment plant-even emergency generators to keep a nitration running in case of power failure. Our telephone: (212) MU 2-2587 Cable: Pharchem

Fisher

chemical company, inc. 355 LEXINGTON AVE., NEW YORK, Ν. Υ. 10017

gamma

chemical corporation GREAT MEADOWS, N. J.

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