Sciencemadness Discussion Board

hydrolysis of polypropylene?

CrossxD - 13-10-2015 at 08:17

I dont know if it is possible, but how about hydrolysis of polypropylene for make isopropyl alkohol?

gdflp - 13-10-2015 at 09:12

You can't just hydrolyze a polymer, you would need to depolymerize it first, then hydrate the alkene, in this case, polypropylene. This won't work in the case of polypropylene, as a complex mixture of products is produced upon thermal cracking of the polymer, instead of cleanly producing the monomer like some polymers. The mixture obtained contains very little propylene and separating it will be an exercise in futility, especially for something as simple as isopropanol.

Hydration of alkenes is quite easy, dilute sulfuric acid accomplishes this quite nicely. However, this particular hydration is complicated by propylene being a gas.

CharlieA - 13-10-2015 at 16:14

(If you are in the USA?), why not just buy isopropyl rubbing alcohol at a drugstore?

CrossxD - 14-10-2015 at 05:33

Im in czech rep. and I can only buy expensive laboratory grade isopropyl alkohol

CharlieA - 14-10-2015 at 06:20

That is a problem! Maybe you buy some from a nearby country.

xfusion44 - 14-10-2015 at 14:54

Quote: Originally posted by CrossxD  
Im in czech rep. and I can only buy expensive laboratory grade isopropyl alkohol


This might help you:

Crude acetone is hydrogenated in the liquid phase over Raney nickel or a mixture of copper and chromium oxide to give isopropyl alcohol. This process is useful when coupled with excess acetone production, such as the cumene process.

Source: https://en.wikipedia.org/wiki/Isopropyl_alcohol

PS: I'd go with copper and chromium oxide process, as Raney nickel is probably harder to get. You can get chromium oxide on ebay and copper is readily available at hardware stores (but you probably already have it enough at home).

[Edited on 14-10-2015 by xfusion44]

[Edited on 14-10-2015 by xfusion44]

[Edited on 14-10-2015 by xfusion44]

kecskesajt - 14-10-2015 at 19:50

Hungary has great price of isopropanol. 5liter is about 20$.But you need to find that place.

CrossxD - 15-10-2015 at 05:25

thank you xfusion I will try it, but if I will depolymerize plastic (PP PE) in higher pressure and temperature it will meka shorter chains right? and if there will be shorter chains there will be more propene right?

CrossxD - 15-10-2015 at 09:12

xfusion do you know what chromium and copper oxide I need?

Amos - 15-10-2015 at 10:44

There are no words.

xfusion44 - 15-10-2015 at 11:01

Quote: Originally posted by CrossxD  
xfusion do you know what chromium and copper oxide I need?


Chromium oxide and copper metal.

Copper metal can be obtained from copper wires.

Chromium oxide is available on ebay: http://www.ebay.com/sch/i.html?_from=R40&_trksid=p205060...

I've never done this reaction, so it'd be good if somebody on this forum could tell us a little bit more about this procedure and possible complications (if any).

Best regards :)

MeshPL - 18-10-2015 at 23:38

In neighboiring Poland isopropanol solvent is easier to come by than ethanol. But only in hardware stores. It is sometimes called Dentatural (ethanol solvent is named Denaturat) and is sold dyed or colorless.

I think it partially replaced ethanol solvent due to issues with people drinking it.

CrossxD - 20-10-2015 at 04:16

poland is near to me thank you very much