在线观看亚洲精品专区-在线观看亚洲免费-在线观看亚洲免费视频-在线观看亚洲欧美-欧美freexxx-欧美free嫩交video

食品伙伴網服務號
 
 
當前位置: 首頁 » 專業英語 » 專業知識 » 正文

分餾

放大字體  縮小字體 發布日期:2008-09-18
核心提示:For many cases, the boiling points of the components in the mixture will be sufficiently close that Raoult's law must be taken into consideration. Therefore, fractional distillation must be used in order to separate the components well by repeated v


    For many cases, the boiling points of the components in the mixture will be sufficiently close that Raoult's law must be taken into consideration. Therefore, fractional distillation must be used in order to separate the components well by repeated vaporization-condensation cycles within a packed fractionating column.

    As the solution to be purified is heated, its vapors rise to the fractionating column. As it rises, it cools, condensing on the condenser walls and the surfaces of the packing material. Here, the condensate continues to be heated by the rising hot vapors; it vaporizes once more. However, the composition of the fresh vapors are determined once again by Raoult's law. Each vaporization-condensation cycle (called a theoretical plate) will yield a purer solution of the more volatile component. In reality, each cycle at a given temperature does not occur at exactly the same position in the fractionating column; theoretical plate is thus a concept rather than an accurate description.

    More theoretical plates lead to better separations. A spinning band distillation system uses a spinning band of Teflon or metal to force the rising vapors into close contact with the descending condensate, increasing the number of theoretical plates.

    許多情況下,混合物中各組分的沸點十分接近,以致于必須將拉烏爾定律考慮在內。因此,為了很好地分離各組分,必須通過在一個填充分餾柱內不斷重復汽化-冷凝周期的方法進行分餾。

    當要被提純的液體受熱時,它的蒸汽上升到分餾柱。蒸汽上升的同時,冷卻并凝結在冷凝器壁和填充物的表面。此時,上升的熱蒸氣使冷凝物繼續受熱,并再一次汽化。然而,新生成的蒸汽的成分再一次取決于拉烏爾定律。每一個汽化冷凝周(稱為一個理論塔板)都會產生一種易揮發組分含量更高的液體。實際上,一定溫度下的每一周期并不是在分餾柱內的同一位置進行的,因而,理論塔板只是一個概念而不是精準描述。

    塔板越多分離越好。旋轉帶蒸餾系統使用一條轉動的特氟綸帶或金屬帶迫使上升的蒸汽與下降的冷凝物緊密接觸,而提高理論塔板數。

更多翻譯詳細信息請點擊:http://www.trans1.cn
 
關鍵詞: 分餾
[ 網刊訂閱 ]  [ 專業英語搜索 ]  [ ]  [ 告訴好友 ]  [ 打印本文 ]  [ 關閉窗口 ] [ 返回頂部 ]
分享:

 

 
推薦圖文
推薦專業英語
點擊排行
 
 
Processed in 0.073 second(s), 15 queries, Memory 0.9 M
主站蜘蛛池模板: 国产精品久久久久久久久免费观看 | 免费一看一级毛片全播放 | 手机看片1024免费视频 | 一区国产传媒国产精品 | 亚洲国产精品第一页 | www.四虎| 男人天堂伊人 | 欧美人与动性行为网站免费 | 九九福利 | 午夜精品视频在线观看美女 | 成人黄色激情网 | 夜夜爽网站 | 俄罗斯aaaaa一级毛片 | 免费啪啪小视频 | 国内一级特黄女人精品毛片 | 国产特级毛片 | 干人人| 欧美最猛黑人xxxx黑人猛交69 | 美女扒开尿口给男人爽的视频 | 三级国产在线 | 久青草视频免费视频播放线路1 | 狠狠色狠狠色狠狠五月ady | 国产精品爱久久久久久久三级 | 丁香视频在线 | 国产成人经典三级在线观看 | 亚洲色图88 | 亚洲高清中文字幕一区二区三区 | 狠狠艹视频 | 亚洲午夜久久影院 | 色视频在线观看 | 特级淫片aaaaa片毛片 | 夜夜精品视频一区二区 | 日本一区二区在线视频 | 免费看美女禁处爆涌视频 | 日日插天天操 | 97精品伊人久久久大香线焦 | 涩涩涩丁香色婷五月网视色 | 国产视频分类 | www.毛片在线观看 | 色在线网站免费观看 | 国产视频分类 |