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muzishi

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[交流] 二氯乙烷如何干燥

二氯乙烷如何干燥？
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通知一下，现在开始打劫了，有钱的赶紧出钱，没钱的赶紧借钱

1楼 2006-09-25 18:04:34

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samuel01

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1,2-Dichloroethane [107-06-2] M 99.0, b 83.4°, d 1.256, n15 1.44759. Usually prepared bychlorinating ethylene, so that likely impurities include higher chloro derivatives and other chloro compoundsdepending on the impurities originally present in the ethylene. It forms azeotropes with water, MeOH, EtOH,trichloroethylene, CC14 and isopropanol. Its azeotrope with water (containing 8.9% water, and b 77°) can be used to remove gross amounts of water prior to final drying. As a preliminary purification step, it can be steam distd, and the lower layer was treated as below.
Shaken with cone H2SO4 (to remove alcohol added as an oxidation inhibitor), washed with water, then dilute KOH or aqueous Na2CO3 and again with water. After an initial drying with CaCl2, MgSO4 or by distn, it is
refluxed with P2^^ CaSO4 or CaH2 and fractionally distd. Carbonyl-containing impurities can be removed as described for chloroform.

以上是试剂纯化手册，Purification of Laboratory Chemicals， Elsevier图书，第5版,这个书上方法我以为最可信。