Fuel cells The US Department of Energy has named three firms to undertake a three-year project to develop the molten carbonate fuel cell for full scale trials.

Contracts go to Energy Research Corp, International Fuel Cells Corp and M-C Power Corp. The most likely fuel is natural gas and the cells operate at high temperatures - over 1200°F.

Krebs promote membrane NaOH recovery Krebs Swiss, of Zurich, has announced that it offers a new membrane technology for recycling sodium hydroxide. The process uses polyvinyl acetate as membrane.

Supply of caustic soda has been tightening in the

wake of reduced demand for chlorine, since most of the world's production is co-produced with chlorine made by the electrolysis route. Production of sodium hydroxide from soda ash, the traditional means of dealing with the imbalance, is also expensive.

Unused caustic soda, used in many industrial applications, can be simply separated and recycled using the membrane, the company says.

PTFE filtration membranes Whatman Scientific Ltd, Maidstone, Kent, UK, say that their hydrophobic PTFE filtration membranes offer a verstile answer to many difficult filtration problems at laboratory scale. The TF microfiltration devices are fitted in strong polypropylene housings, and the chemical resistance of PTFE make the filters ideal for filtration of organic solvents, and also - when pre-wetted with alcohol - for filtering strong acids and bases. They can also be used for air or gas

The Puradisc 25TF microfiltration device, with syringe.

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applications. Several designs are available, including the

disposable Puradisc 25TF, Polydisc TF and Polycap TF. All are supplied ready for use and most are available in 0.1, 0.2, 0.45, and 1.0 micron porosities.

Puradisc 25TF incorporates a 25 mm filter disc. It is intended for maximum sample recovery from small liquid volumes and has inlet/outlet connections which can be used with a syringe. It is particularly recommended for HPLC applications.

Polydisc TF and Polycap TF have 50mm disc and capsule configurations catering for filtration duties up to 20 litres per minute.

Synthetic blood Progress in the development of blood substitutes is moving at such a pace that Thomas K Goldstick, professor of chemical and biomedical engineering at Northwestern University, USA, has predicted that artificial blood could be in widespread use within five to ten years.

Goldstick and co-workers have been conducting tests using fluorocarbons as oxygen carriers. Reporting his findings in at a meeting in Chicago in November, Goldstick said that his investigations were based on a material invented by David Long, MD, previously at the University of Illinois.

It had been known for some time that fluorinated hydrocarbons are effective carriers of both oxygen and carbon dioxide, but hitherto a problem has been that the compounds do not mix with water. Long found a way to emulsify the fluorocarbons with water at up to 52% concentration, and the emulsion of perfluoro-octylbromide is now produced by Alliance Pharmaceutical Corp, of California.

In the tests at Northwestern, small doses of artificial blood resulted in an increase in the amount of oxygen delivered to the retina of cats than that supplied by normal blood alone.

With the fear of contracting contagious disease from conventional blood products, the potential for the so-called "white blood" products may clearly be substantial. However, it is understood that clinical trials using such products were halted early in 1990 by the Food and Drug Administration, FDA, because of the possibility of side effects.

Crossflow clarifier Sartorius Filtration have announced the Sartflow 10 as their most advanced and cost effective unit for clarifying wine, cider and similar products. The company says that it can replace three stages of the

Sartorius' Sartoflow 10 skid-mounted crossflow system.

filtration process normally associated with clarifying such products.

A complete skid-mounted crossflow system, the Sartflow 10 has 10 modules each of 0.7m 2 surface area. A balance tank coupled to pump feeding is incorporated in the module block.

A turbulence inducing separator provides gentle but effective filtration, say Sartorius, with a retentate to filtrate flow rate ratio of 10:1 - the lowest available. Low energy costs and minimal heat pick- up are also claimed.

With automatic reverse feed cycles, reverse flushing is accomplished within 10 minutes. Depending on the product being treated, the unit has a throughput between 150 and 700 litres per hour.

Biotech transfer to Third World The Biotechnology Engineering Centre at Tufts has been awarded a one-year grant from the US National Science Foundation to research the potential for technology transfer in the manufacture of vaccines and pharmaceuticals.

Each year in Africa, Asia and Latin America more than 14 million children under the age of five die from preventable diseases, but development of new

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