Letters

  Nuclear power  

I hardly expected the fawning attitude expressed in "Nuclear Power for the Future" from an ACS publication that should be publicizing the consequences of ignored safety issues (C&EN, Sept. 13, page 31). It seemed to be just a patchwork of Pollyanna claims straight from nuclear industry promotional material. Where is the critical journalism that this very serious subject needed?

Lacking was any discussion of previous industry failures in dealing with a technology where accidents have immense consequences, dwarfing by orders of magnitude anything possible in the chemical industry. Similarly, there was no consideration of the terrorism threat, nor the very serious proliferation implications. Pie-in-the-sky plans were presented as though they could be built in as little as three years, when it has taken the industry several times that long to build past reactors, with massive cost overruns, even with similarly optimistic promises.

To demonstrate the failures in reporting, we need to consider the history and reality of one of the "new" technologies. Years ago in C&EN, pebble bed reactors were billed as a practical source of process heat for the chemical industry, and although experiments have been dismal failures, the article might lead the gullible to think they are again on the horizon. The reality is that pebble bed is just the latest gas-cooled graphite-moderated reactor, a technology plagued by the inconvenient fact that graphite is happy to burn at high temperatures when inert gas coolant is lost. Fair reporting would have pointed out that both Windscale and Chernobyl demonstrated to the ignorant what happens when graphite reactors catch fire.

I should not have to remind other chemists that happy talk is not a plan. "Nuclear Power for the Future" should only remind us that the nuclear industry and some uncritical journalists think it is.

James W. Lewis
Santa Cruz, Calif.

My compliments on the very informative "Nuclear Power for the Future."

I would like to see a similar article devoted to the future of hydrogen. Apparently, industrial hydrogen is now produced by electrolysis and methane cracking. It would appear to me that both of these processes are counterproductive sources of hydrogen for fuel, requiring more energy for production than released by the subsequent combustion.

What is the commercial potential for nuclear thermochemical hydrogen? How much energy is diverted from the usual electrical power generation function? How much hydrogen will a 1,000-MW reactor produce? This subject could be an interesting challenge to your writers.

W. Robert Schwandt
Decatur, Ill.

I found it very disappointing that you would publish an extensive article dealing with the future prospects of nuclear technology without including a single word about the many problems that surround the safe transportation and storage of nuclear waste.

Deciding on a safe location for the storage of nuclear waste and on secure methods for the transportation of that extremely dangerous waste to that site, while it represents a supremely inviting target for terrorists every inch along its way, are problems that, if not solved, could render the future of nuclear technology moot. Surely they deserved consideration in your article. Your failure to address them while painting an optimistic picture for the future of nuclear technology suggests a myopic focus on that technology combined with a sad lack of concern for its societal consequences.

Frank J. Dinan
Buffalo, N.Y.

Thank you for the excellent article on the coming generation of nuclear power plants. Even though I try to follow national nuclear affairs very closely, I have found it hard to get a coherent picture of what is being proposed.

However, as the resident of a state heavily impacted by both military and commercial nuclear waste, I can't help wondering what plans are being made to take care of the deadly waste that will be generated. We in South Carolina are heavily impacted by the detritus from Generations I and II of the last round of power reactors and seem fated to receive even more of the old, soon-to-be decommissioned, highly radioactive reactors for disposal at the ChemNuclear site in Barnwell County. A number of these reactors, classified as Class C low-level waste, are already buried there.

Acceptance of waste from states that are not members of the Atlantic Compact is supposed to be cut off in the year 2008, but given the political realities and the ever-occurring budget shortfalls, don't hold your breath.

Building a new generation of reactors is a bonanza for many special interests, including our major universities, but it would be nice if there was equal enthusiasm, scientific research, and resources devoted to the still-unsolved waste dilemma and to more benign sources of power.

Mary T. Kelly
Columbia, S.C.

The most troubling aspect of the "nuclear promise" was well obscured in Michael Freemantle's "Nuclear Power for the Future." He notes that "existing uranium resources are believed to be sufficient to support a once-through cycle well into this century." To be more precise, even though there has been a global glut (with depressed prices) of enriched uranium for the past 30 years, the International Atomic Energy Agency concludes that the total global uranium reserves (5 million tons) of usable quality are sufficient to sustain nuclear power plants, with a 2% annual growth rate, only through 2040.

Other nuclear physicists have recently concluded that even with near-zero growth, the high-grade ores (those greater than 0.15% uranium) will be depleted within 25 years. Moreover, 15 years after the high-grade ores are depleted, we'll be into the low-grade ores (below 0.02% uranium), which may have negative energy balance and result in more CO₂ emissions (during ore refining, processing, disposal, etcetera) than would be produced by gas-fired power plants.

Still, the Department of Energy shortsightedly focuses on once-through designs and doesn't expect to see Generation IV fast reactors beginning to be utilized until after 2040. Isn't it about time that nuclear proponents face up to the sustainability issues and focus exclusively on concepts that will not leave a fully depleted world for our grandchildren?

F. David Doty
Columbia, S.C.

Too clever for our own good

As an emeritus member of the American Chemical Society, I have been reading C&EN for over half a century and enjoying it for its coverage of the world of chemistry.

Unfortunately, I am noticing that an annoying tendency toward forced and glib jocularity and witticism has been creeping into the magazine.

The following are representative categories of inappropriate whimsy and attempts at being cute, taken from the Sept. 13 issue:

◾ Double entendres: the article title "Fallen Star" and picture caption "Letdown," describing the space capsule Genesis that plummeted to Earth after its parachutes failed to open (page 9); the picture caption "Moving Experience," referring to microparticles whose movements can be controlled by electromagnetic impulses (page 8).

◾ Alliterations: the article title "Shape-shifter" and caption title "Mesophase Morphing," for assemblies of polymer molecules that assume different shapes at different temperatures (page 9); "Hurricane Havoc" (page 1).

Another example of inappropriate nonsense that would make even Edward Lear wince is exemplified by "Look Ma, No Hands" (page 1), referring to the same microparticles on page 8.

Therefore, dear editors of C&EN, please be guided by the motto "KISS," which used to be popular with our undergraduate students. In the present context, it stands for "Keep It Straight" (as opposed to funny) and "Serious" (that is, businesslike).

Hans Schott
Philadelphia

Showdown over absorption

I read with considerable interest the article that described the use of p-tert-butylcalix[4]arene to absorb gases such as CO₂, but not smaller molecules (C&EN, May 31, page 7). The aspect of CO₂ sequestration by guest/host complex formation, at least, is not new. This was discovered at the National Institute of Standards & Technology by T. J. Bruno and colleagues several years ago [J. Inclusion Phenom. Macrocyclic Chem., 43, 179 (2002)].

Moreover, p-tert-butylcalix[4]arene was used in a patented process to remove carbonyl sulfide from fuel gases (U.S. Patent No. 6,334,949, Jan. 1, 2002). Unfortunately, neither of these earlier works is mentioned in the C&EN article, and neither is cited in the Jerry L. Atwood paper [Angew. Chem. Int. Ed., 43, 2948 (2004)].

Paris Svoronos
Bayside, N.Y.

Atwood and Leonard J. Barbour respond: We did not reference the two earlier papers noted by Svoronos simply because they are not relevant to our work.

First, the focus of our paper was on the gas sorption properties of a new type of material exemplified by a particular, seemingly nonporous polymorph of p-tert-butylcalix[4]arene that absorbs and concentrates gases to a remarkable extent at 1 atm pressure. A cursory reading of our article (and the C&EN article) makes this clear.

Second, the absorption of CO₂ reported by Bruno and colleagues occurred in liquid CO₂, at about 300-atm pressure of CO₂. These experimental conditions are vastly different from those we employed.

Third, the characterization reported by Bruno is quite limited. The patent reference contains only one experimental result, and in that one, incredibly, the authors find that each p-tert-butylcalix[4]arene molecule in the solid state absorbs 4.4 CO₂ molecules.

We agree with Svoronos that "CO₂ sequestration by guest/host complex formation, at least, is not new." This was not, however, discovered by Bruno at NIST. Even if the NIST researchers had presented an acceptable level of characterization of their CO₂ host/guest complex, they were still 46 years too late to receive credit for the discovery.

F. Cramer and F. M. Henglein prepared and characterized the host/guest complex of -cyclodextrin with CO₂ (among other gases) in 1956. A nice account of this and related work is found on pages 310 and 311 in volume three of "Comprehensive Supramolecular Chemistry" (Pergamon, 1996).

The publications referred to by Svoronos were also not cited in the two excellent recent reviews by Dmitry M. Rudkevich: "Emerging Surpamolecular Chemistry of Gases" [Angew. Chem. Int. Ed., 43, 558 (2004)] and "Molecular Encapsulation of Gases" [Aust. J. Chem., 57, 713 (2004)].