Nitrogenase analog makes hydrazine from N - C&EN Global

Nov 7, 2010 - A new way to make hydrazine directly from gaseous nitrogen, rather than from ammonia, the starting material for industrial production, h...
0 downloads 0 Views 94KB Size
Other agencies fault EPA's acid rain plan The U.S. acid rain control strategy now being crafted by the Environmental Protection Agency is receiving a less-than-favorable reception from other government agencies. Their objections have succeeded in derailing temporarily the schedule set by EPA Administrator William D. Ruckelshaus, who had planned to make his recommendations to the President by the end of September. The plan, a targeted sulfur dioxide emissions reduction program, is being shaped under the close scrutiny of Ruckelshaus and his deputy administrator Alvin L. Aim. It is being condemned as precipitous and costly by officials from the Office of Management & Budget, and the departments of Energy and Interior. What these officials object to, but what knowledgeable EPA staff members expect will emerge as the program Ruckelshaus presents to President Reagan, is a phased emissions reduction strategy involving only 10 to 12 states and an annual sulfur dioxide emissions cut of 3 million to 4.5 million tons. This experimen-

tal control program, expected to cost up to $2.5 billion, would be imposed initially on sulfur dioxideemitting sources in the Midwest, especially those in Ohio, in Pennsylvania, and possibly sources in Vermont and New Hampshire. If significant reduction in acidic deposition is achieved in the most acid rainstressed areas the program could be extended to other states, EPA argues. Yet, when Ruckelshaus presented his limited scheme to the Cabinet Council on Natural Resources two weeks ago, it was rejected and sent back to EPA for more analysis. A knowledgeable observer says Reagan must offer Congress an Administration position "to tone down the acid rain proposals" pending. But this source says, "There is no strong pressure on the Administration to be timely; Reagan can wait until the end of the year" before he loses credibility on the issue. Sen. Robert T. Stafford (R.-Vt.), chairman of the Environment & Public Works Committee, recently pegged an annual 8 million ton reduction "a barely acceptable minimum effort" and forecast a bitter Congressional battle if the Administration offered a reduction plan less than that. •

Nitrogenase analog makes hydrazine from N 2 A new way to make hydrazine directly from gaseous nitrogen, rather than from ammonia, the starting material for industrial production, has been discovered at the University of Nebraska, Lincoln, by chemistry professor T. Adrian George and graduate student Lenore M. Koczon. Hydrazine is used as a rocket propellant and is also an important chemical intermediate. The method involves reactions of a stable molybdenum-based inorganic complex that can bind nitrogen directly to the metal. The compound is a synthetic analog of the molybdenum-containing nitrogenase enzyme produced by nitrogen-fixing microorganisms. George notes that the enzyme analog has a molecular weight of about 1100 and that it contains organic phosphine ligands, which, apparently, are the key to its stability. When the complex, dissolved in

toluene, is treated with a strong acid such as hydrogen bromide, the nitrogen is converted to hydrazine, with about 50% yield, George says. But if the reaction is carried out in a more polar ether-type solvent, such as tetrahydrofuran (THF), the nitrogen is instead converted to ammonia. In "natural" nitrogen fixation, ammonia, not hydrazine, is the product. However, George says, if the enzyme is quenched with acid or base during nitrogen fixation, hydrazine is detected. Similarly, in the ammonia-forming reaction in THF, if the synthetic analog is quenched with water, hydrazine also is detected. The work is an outgrowth of basic research, funded by the National Science Foundation, on synthetic nitrogenase analogs. Although the idea is attractive, George doesn't speculate on the industrial potential of the process. •

Dioxin accident trial finds defendants guilty The aftermath of a chemical plant explosion seven years ago at Seveso, in northern Italy, resulting in dioxin contamination in parts of the town, is winding its way to conclusion. One of the last chapters is the trial in Monza, Italy, of five present and former employees of Swissbased Givaudan and its Italian subsidiary Industrie Chemiche Meda Societa, Anonima (ICMESA), which operated the plant. Late last month the trial wound up after six months with all five defendants judged guilty. Four were convicted of having voluntarily omitted equipping the ICMESA trichlorophenol production plant with adequate security systems; the court commuted three years of the four- and fiveyear sentences. The fifth defendant was convicted of having negligently provoked a disaster; his 30-month sentence was totally commuted. Givaudan, which has been haunted by the Seveso accident, says that it and its Swiss parent HoffmannLa Roche "appreciate the fact that the trial was conducted in a fair manner. We therefore regret all the more that the court has decided to accept much of the state attorney's argument that the Seveso accident could have been foreseen, although in our opinion, no convincing evidence in support of that view was presented during the trial." Meanwhile, a week before that decision, the town of Seveso had accepted a $7 million or so compensation offer from Givaudan, dropping its civil claims and its claims in the trial at Monza. The company already has paid out nearly $100 million in settlements with other Italian authorities and individuals. Earlier this summer, 41 drums of dioxin-contaminated wastes from Seveso became a center of controversy when they were "lost" for a while in France during shipment for disposal (C&EN, June 6, page 61). Ciba-Geigy since has agreed to incinerate the wastes for Givaudan and currently is conducting toxicity tests jointly with La Roche in preparation for incineration, tentatively scheduled for next spring. • October 3, 1983 C&EN

5