????我們在2007年曾對丁醇進行過報道，這種生物燃料擁有解決乙醇很多問題的潛力。從那時起，英國石油公司（BP）這樣的業(yè)內(nèi)廠商一直在努力尋找辦法以具有成本效益的方式向這種“先進生物燃料”過渡，現(xiàn)在一項科研突破可能最終使這一切成為現(xiàn)實。

????丁醇在很多方面都勝過乙醇：在汽油中添加乙醇會降低燃油里程，但丁醇可以提供跟汽油幾乎等量的能量，意味著消費者加油的次數(shù)可以少一些；丁醇也不會像乙醇那樣對汽車發(fā)動機造成損傷，因此可以將更多的丁醇混入汽油當中；另外，丁醇不會因為雜質水的存在而跟汽油分離，煉油廠可以直接進行混合操作，而乙醇需要跟汽油分開來運輸，然后在加油站附近進行混合。

????然而，美國已經(jīng)有200家乙醇工廠建成投產(chǎn)，在這種情況下，乙醇的市場地位根深蒂固。如果要將那些工廠改造成利用玉米生產(chǎn)丁醇而不是乙醇，它的單位成本大約為1,500萬美元。從理論上說，將乙醇轉化為丁醇更加便宜，但業(yè)界一直在尋找一種化學催化劑，以使這個過程更加高效。直到目前，這個轉化過程產(chǎn)生的丁醇太少，而需要分離出來的雜質卻過多。英國布里斯托爾大學（University of Bristol）的化學教授鄧肯?沃斯說，這個過程“當然太過昂貴，無法成為一種具有競爭力的燃料選擇?！?/p>

????沃斯在美國新奧爾良舉行的美國化學學會（American Chemical Society）年會上展示了自己的研究成果（由英國石油公司資助），他發(fā)現(xiàn)一族新的催化劑可以在實驗室中轉化出95%的丁醇。沃斯說：“它們有希望以高產(chǎn)量、高選擇性和大規(guī)模生產(chǎn)的方式將乙醇轉化成丁醇。”

????我們?nèi)匀灰^一段時間才能開始在加油站看到利用沃斯的催化劑生產(chǎn)出的丁醇——僅僅是設計和建造轉化設施以及在實驗工廠對新燃料進行規(guī)?；瘻y試就需要耗費數(shù)年的時間。沃斯估計，如果接下來的事情一切順利，這種工藝需要6年時間才能實現(xiàn)商品化。

????不過到那時候，我們不就是在拿一種用糧食制成的燃料替換另一種燃料嗎，那不是從我們后代的口中搶糧食嗎？沃斯表示：“這些催化劑的美妙之處在于，它們可以應用于各種來源（通過生物技術利用各種作物制成）的乙醇?！笨茖W家們正在研究將玉米秸稈、木材、樹葉以及柳枝稷作為提取非糧生物燃料的來源。（財富中文網(wǎng)）

????譯者：王燦均

????In 2007 we reported on biobutanol, a biofuel with the potential to solve many of the problems associated with ethanol. Since then, industry players like BP have been seeking ways to make a cost-efficient transition to the "advanced biofuel," and now a scientific breakthrough might finally make that possible.

????Butanol trumps ethanol in several ways: Adding ethanol to gasoline reduces fuel mileage, but butanol packs almost as much energy as gas, meaning fewer fill-ups. Butanol also doesn't damage car engines like ethanol, so more of it can be blended into gas. And because butanol doesn't separate from gasoline in the presence of water, it can be blended right at the refinery, while ethanol has to be shipped separately from gas and blended closer to the filling station.

????But with 200 plants already up and running in the U.S., ethanol is firmly entrenched. Modifying those plants to produce butanol from corn instead of ethanol costs roughly $15 million for each facility. Converting ethanol into butanol could be cheaper, theoretically, but the industry has been looking for a chemical catalyst capable of doing it efficiently. Until now, the conversion process produced too little butanol and too many unwanted products that had to be separated out. The process was "certainly too expensive to be competitive as a fuel molecule," says Duncan Wass, a professor of chemistry at the University of Bristol in the U.K.

????At the annual American Chemical Society meeting in New Orleans, Wass presented research -- funded by BP (BP) -- on a family of new catalysts that produced 95% butanol in the lab. "They hold the prospect of being able to convert ethanol to butanol in high yield, high selectivity and at large-scale," Wass says.

????It will still be some time before we'll start seeing butanol produced with Wass's catalysts at the pump -- it takes several years just to design, build, and test new fuels at scale in a pilot plant. Wass estimates it will be six years to commercialization if the next steps go off without a hitch.

????But at that point, won't we just be trading one food-based fuel for another, taking corn out of the mouths of babes? Says Wass, "The beauty of these catalysts is that they can use all sources of ethanol biologically derived from any crop." Corn stalks, wood, leaves, and switch grass are all being studied as sources of non-food biofuel.