科技新知....用水發動的汽車引擎可望成真

透過把水與一種鋁鎵合金(aluminum-gallium)的珠狀粒子相混合產生氫(hydrogen)的方法，美國普渡大學(Purdue University)一位電子工程學教授找到了一種汽油的替代方案。由於鎵在化學反應中不會被消耗，而鋁能被循環使用，此一發現可望使未來汽車引擎可用水取代汽油來發動。

普渡大學已為上述技術申請了專利，並獨家授權給位於印第安那州的一家新創公司AlGalCo。電子工程學教授Jerry Woodall是在實驗室中清洗一個含有液態鎵和鋁合金的坩鍋(crucible)時，偶然地擁有以上的發現。「當我把水添加到這個合金當中時，產生了一個猛烈的吹氣聲，」Woodall表示：「當液態合金中的鋁原子與水接觸時，它們之間發生了反應，使水爆裂開，並產生氫氣和鋁氧化物。」

Woodall表示，水燃料引擎要邁向商業化，還有一些製程上的瓶頸有待克服；不過他也強調，該技術最終可應用於直接燃燒氫的引擎，或是為氫燃料電池充電。Woodall也透露，上述化學反應不會產生有毒的副產品，一磅的鋁能產生2千瓦的功率；一輛行駛350英哩的汽車，將消耗約350磅、價值約60美元的鋁，而且化學反應後留下的氧化鋁還能被還原回鋁鎵顆粒物供循環使用。

參考原文 :

Water-fueled engine appears on the horizon

R. Colin Johnson

EE Times (05/16/2007 1:49 H EDT)

PORTLAND, Ore. — An EE professor at Purdue University has found a way to produce hydrogen that replaces the need for gasoline by mixing water with beads of an aluminum-gallium alloy. The discovery could lead to engines that essentially burn water, instead of gasoline, since the gallium is not consumed in the reaction and the aluminum can be recycled. Purdue has patented the process and has issued an exclusive license for it to an Indiana startup company, AlGalCo LLC. EE professor Jerry Woodall discovered the process in the lab by accident, while cleaning a crucible containing liquid alloys of gallium and aluminum "When I added water to this alloy, there was a violent poof," said Woodall. "When the aluminum atoms in the liquid alloy came into contact with the water, they reacted, splitting the water and producing hydrogen and aluminum oxide." Woodall claims that several industrial process problems need to be solved before the water-fueled engine can become commercially viable. But eventually, he said, it could be used both in engines that burn the hydrogen directly and to charge up hydrogen fuel cells. The reaction has no toxic by-products and can produce two kilowatt hours of energy from a pound of aluminum, said Woodall. For a 350-mile trip in an automobile, it would take about 350 pounds of aluminum at a cost of about $60, since the aluminum oxide left over after the reaction could be converted back into aluminum-gallium pellets for reuse.