(Master Searcher)
02-26-03 02:15
No 411687
(Rated as: excellent)
From CA vol 11 page 2807.
Absolute alcohol. L. SOLARI. Swiss 74,943, May 1, 1917. Alc. is dehydrated by means of anhydrous CuSO4 in a vessel provided with a stirring mechanism, continuing the treatment for 10-12 hrs., and operating preferably at 45 °.
Can someone translate this?
Patent CH74943
I wonder how effective CuSO4 would be with other solvents or solutions.
http://www.geocities.com/dritte123/PSPF.
The hardest thing to explain is the obvious
(Hive Bee)
02-28-03 00:11
No 412388
(Rated as: excellent)
(...) With this procedure the ordinary 95° alcool can be dehydrated easily to 99/100°.
Experimental:
Anhydrous copper sulfate, obtained by the calcination of ordinary hydrated copper sulfate (or by another way), is added to the alcohol you want to dehydrate in an apparatus with a stirbar and is left in contact for 10-12 h, with stiring from times to times. If some heat is applied, like 45°C, the process is faster.
It is good to put twice the theoretical amount of anhydrous CuSO4, for the reaction to not take too much time. For instance, with 100 kg of 95° alcohol, it take 20 to 25 kg of anh. CuSO4. At the end of the reaction the clear liquid is decanted and can be filtered to remove the remaining CuSO4 suspended, or can be placed in a tank to sediment. If distillation of the alcohol is performed instead of decantation, some water is left in the alcohol. Yields are 85 to 90% of 99° alcohol (measured on the initial quantity of pure alcool). The remaining alcohol impregnated on the hydrated CuSO4 is recovered by distillation. This fraction is not anhydrous and must be recycled in another experiment.
If really absolute alcool is necessary, it is good (to save time and to not put too much sulfate at once) to put the 99° alcohol on fresh anhydrous copper sulfate which then react faster. The hydrated CuSO4 is calcinated and recycled.
Some changes can be made on the procedure without much problem.
(Master Searcher)
03-01-03 01:45
No 412662
Thanks, Chimimanie. I had someone read this to me and there's no discussion of prior art (ie. other references) and/or comparison to other drying agents.
http://www.geocities.com/dritte123/PSPF.
The hardest thing to explain is the obvious
(Newbee)
03-01-03 07:13
No 412717
1927 was published a drying method with CaO:
Zeitschrift Spiritusindustrie 1927, 26
Alcohol (~95%) is stirred 1 hour with CaO at 130 degrees (5 bar); yield 98% of absolute Alcohol.
(Master Searcher)
03-31-03 00:53
No 422597
(Rated as: excellent)
Here's an abstract from CA volume 4 page 905 which uses anhydrous CuSO4 for making ethyl acetate.
Ethyl Acetate. JOSEF HABERMANN AND H. BREZINA. Tech. Hochschule, Brünn. J. prakt. Chem., 80, 349-354. - A mixture of 400 g. of 96 % alc., 240 g. glacial AcOH, and 160 g. anhydrous CuSO4 is kept at the ordinary temp. for 24 hr., and is then heated for 12-14 h. on the H2O bath in both cases with frequent shaking. The liquid is decanted from the CuSO4, heated again for 10 h. with another 50 g. of anhydrous CuSO4, then distilled after the removal of the metallic salt. The distillate is fractionally distilled, and the main fraction, b. 70-2°, is repeatedly washed with saturated brine, dried by ignited MgSO4, and again distilled. The distillate b. 70-2°, and has vapor density corresponding with that of an equimol. Compd. Of EtOH and AcOEt. By prolonged shaking with CaCl2, the EtOH seems to be removed, for the liquid now has b. p. 77° and a vapor density corresponding to that of AcOEt. A small quantity of the same comp., b. 70-2°, can be isolated from conc. AcOEt by systematic fractionation.
B. F. PARLET BRENTON.
http://www.geocities.com/dritte123/PSPF.
The hardest thing to explain is the obvious