China wholesale HUAFU China R417a for Italy Factory
product information Name：R417A Brand：HUAFU Producer：No.48 Donggang 1st Road, Quzhou City,Zhejiang,China Storage：In shade,not direct to sunlight Product property: MW:106.75 Boiling point:-41.8℃ Critical temperature :89.9℃ Critical Pressure :4.10Mpa ODP:0.000 Packing : Disposable cylinder 251bs/11.3kg , Recyclable cylinder :926L ;ISO-TANK Quality standard: Purity :≧99.8% Moisture :≦10ppm Acidity:≦1ppm Vapor Residue :≦100ppm Appearance :Colorless ,Odorless Application: Replacement of R22
China wholesale HUAFU China R417a for Italy Factory Detail:
Producer：No.48 Donggang 1st Road, Quzhou City,Zhejiang,China
Storage：In shade,not direct to sunlight
Critical temperature :89.9℃
Critical Pressure :4.10Mpa
Disposable cylinder 251bs/11.3kg ,
Recyclable cylinder :926L ;ISO-TANK
Vapor Residue :≦100ppm
Appearance :Colorless ,Odorless
Replacement of R22
Product detail pictures:
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We prepare diethyl oxalate via the reaction between oxalic acid and ethanol under reflux, then purify our product by distillation and then finally by washing to give a good yield.
This is a quick video showing how to make diethyl oxalate, an ester which we’re planning to use in an up-coming reaction.
We’re starting here with 100 grams of oxalic acid dihydrate. To get a good yield we’ll first need to convert this into anhydrous oxalic acid.
Pour into a pyrex baking tray and bake in the oven at 140 degrees C for 2 hours.
Break up the solid occasionally and then at the end weigh the white powder that remains.
After 2 hours in the oven the crystals look slightly different and the weight has decreased to 74 grams.
This is good enough.
Place the relatively anhydrous oxalic acid into a 500ml flask.
Now prepare 200ml of absolute ethanol. It is important that this is water-free for a good yield.
Add this to the flask.
The esterification is catalysed by acid, and oxalic is strong enough to act as its own catalyst.
You can add 1ml of concentrated sulfuric acid to the mixture but we’re found it makes little difference.
Give the mixture a stir and you’ll see that most of the acid goes into solution in the ethanol, but there’s no reaction as yet.
Now attach a condenser and set up for reflux.
Get a strong reflux going in the flask and keep this going for 2 hours.
Over this time you won’t see much visible change in the reaction mixture.
Here we are after 2 hours of refluxing. There’s hardly any visible change but the mixture has a pleasant and definite slightly sweet smell of rum.
This is due to small amounts of impurity which we’ll remove.
Our next step is to remove excess ethanol. So allow the flask to cool slightly and then set up for simple distillation.
We allowed the flask to cool down to room temperature first to see if any oxalic acid crystallised out. None did as you can see here.
Set up for distillation. We used a thermometer to track the different fractions coming off the liquid.
First off is excess ethanol around 80 degrees C.
There is probably some water in here as well as the azeotrope, but we collected around 120 ml.
Then the temperature of the vapours rose to 100 degrees and we collected pure water.
Then the temperature rose still further to around 160 degrees and we started to collect a colourless liquid.
The temperature of the vapour then rises to around 175 degrees C at the end of the distillation.
During the distillation you’ll see some smoke-like fumes appearing in the apparatus. This is almost certainly excess oxalic acid decomposing.
This means that there may be a small amount of water carried over into our product, but it also means that there are also potentially some fumes of carbon monoxide being formed as well.
This is highly toxic so be careful and use adequate ventilation as it is colourless and odourless and won’t give you any warning.
At the end of the distillation a small amount of char remains in the flask, but nothing else.
Here’s our distillate starting from 160 degrees C. It is fairly pure but does contain a small quantity of water and decomposition products.
So prepare 40ml of a saturated solution of sodium chloride in water.
Add the crude prodduct to a separating funnel and then add the saturated sodium chloride solution – this should sink to the bottom.
Shake the mixture well and then allow the laters to separate. Our product is the top layer.
Separate off the bottom brine layer which should now contain any residual alcohol, formic acid and any other water soluble impurities.
And we’re left with our product. Separate this off into a storage container. You can also dry it using anhydrous calcium chloride if you want to.
And here’s our product. 70g of diethyl oxalate. This is a 60% yield on the starting oxalic acid dihydrate.
For information the weight difference between the distillate collected and the final product was only 2 grams.
The product has a slightly oily consistency and an unusual fresh and fruity aroma a bit like grape juice.
It dissolves very slightly in water and easily forms a bottom layer.
Thanks for watching and stay tuned for more reactions.
By Jamie from Juventus - 2016.01.11 17:15
Superb technology, perfect after-sales service and efficient work efficiency, we think this is our best choice.
By Jenny from Ecuador - 2016.07.07 13:00