氫與工業(yè)
Hydrogen,the lightest and simplest of the elements, has several properties that make it valuable for many industries. It releases more heat per unit of weight than any other fuel.In rocket engines, tons of hydrogen and oxygen are burned, and hydrogen is used with oxygen for welding torches that produce temperatures as high as 4, 000 degrees F and can be used in cutting steel. Fuel cells to generate electricity operate on hydrogen and oxygen. Hydrogen also serves to prevent metals from tarnishing during heat treatments by removing the oxygen from them. Although it would be difficult to remove the oxygen by itself, hydrogen readily combines with oxygen to form water, which can be heated to steam and easily removed. Hydrogen is also useful in the food industry for a process know as hydrogenation. Products such as margarine and cooking oils are changed from liquids to semisolids by adding hydrogen to their molecules. Soap manufacturers also use hydrogen for this purpose. Hydrogen is also one of the coolest refrigerants. It does not become a liquid until it reaches temperatures of -425 degrees F. Pure hydrogen gas is used in large electric generators to cool the coils. In addition, in the chemical industry, hydrogen is used to produce ammonia, gasoline, methyl alcohol, and many other important products.
氫作為最輕和最簡(jiǎn)單的無(wú)素，有幾種特性對(duì)工業(yè)非常有用。 作為燃料，它每單位重量釋放熱量最多，在火箭的引擎中，成噸的氫和氧被燃燒掉。 氫和氧合在一起用于焊接，能夠產(chǎn)生高達(dá)華氏四千度的高溫而可以切割鋼鐵。發(fā)電的燃料房就是使用氫和氧。氫也可以用來(lái)在金屬熱處理中通過(guò)從中除去氧的方法來(lái)防銹。雖然單獨(dú)除去氧本身是困難的，氫和氧很容易結(jié)合成水，而水是可以加熱蒸發(fā)除去的。 氫在食品工業(yè)中對(duì)于所謂的氫化過(guò)程也很有用。 人造黃油和食用油的分子中加上氫，就由液態(tài)變成半固態(tài)。 肥皂制造商也為此使用氫。 氫是溫度最低的冷凍劑。 它要到華氏-425 度才會(huì)液化。 純氫被用于大型發(fā)電機(jī)線圈的冷卻。 除此之外，在化學(xué)工業(yè)中，氫被用來(lái)制造氨、汽油、甲醇以及其它許多重要產(chǎn)品。