Sciencemadness Discussion Board - Preparation of H2SO4 from Bleach, Sulfur and Vinegar

Preparation of H2SO4 from Bleach, Sulfur and Vinegar

AJKOER - 7-5-2011 at 06:19

Hi:

Waiting on my sulfur to perform the following cheap and simple way to make H2SO4. Comments and suggestions welcomed.

1. Prepare HClO (Hypochlorous Acid)

Mix equal parts of Bleach (composed of 6% NaClO, NaCl and some NaOH) and Vinegar (Acetic Acid CH3-COOH, abbreviated to HAc and Sodium Acetate, as NaAc). One can also use very weak mineral acids that you happen to have on hand, Carbonic Acid (H2CO3 takes longer), Ascorbic Acid, Critic Acid, etc.
NaClO + HAc = NaAc + HClO

At this juncture one could either distill (best done outdoors) the solution to purify the HClO, or add distilled water to increase stability of HClO and to aid in crystallization that occurs upon freezing to separate out Sodium Acetate Hydrate (CH3COONa.3H20).

Note: HClO does decompose to HCl and HClO3. How rapidly depends on the HClO concentration (best kept diluted) and temperature.

2. Add Sulfur (S). Per Watts' Dictionary of Chemistry Volume 2 Page 16, even dilute solution of HClO can oxidize Sulfur to H2SO4.

To quote the relevant section from Watts':
"Reactions.--1. HClOAq acts generally as an oxidiser; it easily parts with 0 while HClAq remains. Thus, As is rapidly oxidised with evolution of light; P, S, Se, Br, I are converted to H3P04Aq, H2S04Aq, &c., even by dilute HClOAq; lower oxides or salts are converted into higher, e.g. SO2Aq to H2SO4Aq, FeO to Fe203, As203Aq to As2O5Aq, FeS04Aq to Fe2(S04)3Aq, Fe2Cl6Aq, and Fe2O3, MnSO4Aq to MnO2; sulphides yield sulphates, c.g. H2SAq gives" H2SO4,Aq and S; NH3 gives N,H2O,and NH4CLAq; HC1 forms H20 and Cl. The quantity of the acid expressed by the formula HC1O oxidises the same mass of an oxide"

Note, this preparation can just as easily make Phosphoric Acid if one has access to phosphorous (or a salt?). Other halogen acids and their salts can be prepared as well. For example, substituting Iodine for Sulfur results in Iodic Acid (HIO3), substituting Bromine produces Bromic Acid (HBrO3), etc.

Link to free Google online book. Click View Sample.
http://books.google.com/books/reader?id=ijnPAAAAMAAJ&dq=...

hissingnoise - 7-5-2011 at 06:50

Quote:

Waiting on my sulfur to perform the following cheap and simple way to make H2SO4. Comments and suggestions welcomed.

You may indeed prepare H2SO4 in this way but it will be so dilute and contaminated as to be unusable . . .
Can't you just buy the stuff?

Random - 7-5-2011 at 07:00

You could easily make it by bubbiling SO2 through H2O2, bubbling SO2 through HNO3 (nitrogen oxides are produced!) or by electrolysis of copper sulphate.

Bot0nist - 7-5-2011 at 07:15

The lead chamber process has also been tried here with some success. Decomposing of KNO3 to oxidize the SO2 before dissolution. Making H2SO4 in different was is fun and a great learning experience. As far as economy and practicality is concerned, it's not worth it IMO. Sulfuric is one of the most produced industrial chemicals on earth and is readily available from so many sources. Even some OTC drain openers are of remarkable purity considering there purpose and price.

Please don't get me wrong though. Keep up the experimenting. I love to read round about methods for chemicals from OTC sources, but if you need the acid for synthesis and are not just sything it for fun, I recommend finding a source.

[Edited on 7-5-2011 by Bot0nist]

hissingnoise - 7-5-2011 at 07:20

Sulphur is oxidised to H2SO4 by HNO3 when the mixture is heated to boiling . . .
H2SO4 boils @ 337°C!

blogfast25 - 7-5-2011 at 07:31

I guess it’s a tribute to human ingenuity, this seemingly infinity capacity to devise complicated schemes to make OTC materials in (almost irrecoverably) dilute and complicated solutions.

Dude: Draino (drains unblocker) is 95 % H2SO4, at my local hardware store £5 for a liter. Get some. NOW.

Watt’s Chemical Dictionary, excellent vintage at 1889. ‘Nuff said… It's chemical archaeology...

sternman318 - 7-5-2011 at 09:11

Quote: Originally posted by blogfast25

I guess it’s a tribute to human ingenuity, this seemingly infinity capacity to devise complicated schemes to make OTC materials in (almost irrecoverably) dilute and complicated solutions.

Dude: Draino (drains unblocker) is 95 % H2SO4, at my local hardware store £5 for a liter. Get some. NOW.

Watt’s Chemical Dictionary, excellent vintage at 1889. ‘Nuff said… It's chemical archaeology...

I thought draino was NaOH?

hissingnoise - 7-5-2011 at 09:25

If it's a chemical that cleans drains, it's draino (drano)!

Arthur Dent - 7-5-2011 at 10:33

A bit of clarification... Often, drain cleaner is indeed NaOH, the best known household product being Drano Crystals, which is sodium hydroxide prills with colorants and it contains aluminum turnings too so that when it's in contact with water, it "fizzes" vigorously (giving the impression that it's actively "melting" your clog).

But on the other end of the pH spectrum, there's also industrial grade drain cleaners that are nearly pure sulphuric acid, and basically perform the same thing as above, attacking the clog with a highly corrosive substance, enough that it softens and loosens a clog of organic material until it passes.

Basic drain cleaners often come in solid form (although there are exceptions, Kwik Wipes comes in liquid form), and acidic drain cleaners always come in liquid form.

Robert

AJKOER - 7-5-2011 at 11:31

To reply to some of the points made.

1. HClO produced is impure. I disagree, as bleach, to begin with, can have very limited metal impurities (especially manganese, lead, copper or iron) as the NaClO would quickly be salt and water before the bleach was ever sold. Also, the HClO, if distilled off, is pure. It is recommended to distill off only half of the reaction solution as much more than 50% of HClO will have been captured (saves time and concentrates).

2. Is Sulfuric (or Phosphoric or Iodic depending on what is dissolved into the HClO) Acid produced necessarily dilute? Not necessarily, in my opinion, as the product of the reaction chain is:

2 HClO + S = SO2 + HCl
SO2 + HClO = SO3 + HCl
SO3 + H20 = H2SO4

So 3 moles of HClO produces 1 mole of H2SO4 and the reactant mixture loses 1 mole of water and gains 2 moles of HCl. So we have 3 moles of strong "acid" produced, consume 3 moles of HClO and lose 1 mole of water. So, we have concentrated the original HClO solution total acid strength.

woelen - 7-5-2011 at 11:46

This method is of academic interest only. It is interesting to know that hypochlorous acid is capable of oxidizing many elements to their maximum oxidation state (e.g. sulphur's maximum oxidation state is +6). But this only is interesting from an academical point of view, or maybe in some analysis methods (e.g. a method for determining total sulphur content in a mix can be oxidized completely and then all sulphur is measured as sulfate).

For synthetic purposes this method is useless. Period!

If you really want sulphuric acid, then indeed try to find a source which is willing to sell it to you. Another somewhat easier method may be to bubble SO2 (made from sodium- or potassium metabisulfite and conc. HCl) through a solution of H2O2 until the liquid starts to smell of SO2. Then boil off the SO2 and what remains behind is dilute but fairly pure H2SO4. This can be concentrated further. This method, however, requires access to hydrochloric acid and hydrogen peroxide of reasonable concentration (e.g. 10% or better).

blogfast25 - 7-5-2011 at 12:00

Your reactions are all wrong as well.

2 x [HClO + 2 H+ + 2 e === > HCl + H2O]

S + 2 H2O === > SO2 + 4 H+ + 4 e

HClO + 2 H+ + 2 e === > HCl + H2O

SO2 + H2O === > SO3 + 2 H+ + 2 e

SO3 + H2O === > H2SO4

Add all up:

3 HClO + S + H2O === > H2SO4 + 3 HCl

Start from say 5 % NaClO (approx. commercial thin bleach), that’s roughly 0.6 M hypochlorite. Assuming (naively) 100 % conversion of all steps, that means you’re now 0.2 M H2SO4 and as a bonus [cough!] also 0.6 M in HCl, not to mention your acetate. It’s what they call a witches brew, although I like to believe most witches know better how to spend their money…

[Edited on 7-5-2011 by blogfast25]

bob800 - 7-5-2011 at 12:03

Here's an interesting preparation from an old Popular Science magazine which only requires sulfur, water, and iron oxide:
http://blog.modernmechanix.com/2008/03/05/dangerous-acids-ma...

However, this still isn't a very practical route for any significant amounts of acid.

condennnsa - 7-5-2011 at 13:38

I wonder how come the NaOH in the drano doesn't react with the Al since they're already mixed, right?
I suppose that NaOH can be completely dehydrated by heating to its melting point , whereas as far as I know KOH will keep ~15% water , by the way how is anhydrous KOH made?
i remember reading somewhere that it's very expensive, several times than regular KOH

The best OTC source that I have for H2SO4 is as car battery electrolyte, 1L of 35-40% for $1.5, very pure, completely colorless.

AJKOER - 7-5-2011 at 15:14

OK, thanks for the feedback.

I will change the process and use HTH Bleaching Powder which is 30% available chlorine. React with H2CO3 in a close chamber and produce HClO(Aq). Per the reference below (Watts' Dictionary of Chemistry, Volume 2, page 16), the concentration of Hypochlorous Acid on a single distillation can be nearly doubled:

"A dilute solution of HC10 may be distilled with partial decomposition, the distillate is richer in HC10; Gay-Lussao found that, on distilling a dilute solution to one-half, the distillate contained five-sixths of the total HC1O (C. R. 14, 927)"

Another reference suggests twice distilled to further concentrate as needed. My understanding of why this concentrating effect is occurring is that the gaseous anhydride of HClO (Dichlorine Monoxide or Cl2O) is boil off 1st.

The final product upon oxidation of the sulfur should be a very strong acid solution consisting of HCl 3 parts to 1 part H2SO4 (but still low strength with respect to H2SO4 content only). If any of the HClO is converted to HClO3 during the distillation, the product will not only be strongly acidic, but a strong oxiderizer as well.

Mr. Wizard - 7-5-2011 at 15:35

Quote: Originally posted by hissingnoise

If it's a chemical that cleans drains, it's draino (drano)!

moron

Random - 7-5-2011 at 15:40

Quote: Originally posted by AJKOER

OK, thanks for the feedback.

I will change the process and use HTH Bleaching Powder which is 30% available chlorine. React with H2CO3 in a close chamber and produce HClO(Aq). Per the reference below (Watts' Dictionary of Chemistry, Volume 2, page 16), the concentration of Hypochlorous Acid on a single distillation can be nearly doubled:

"A dilute solution of HC10 may be distilled with partial decomposition, the distillate is richer in HC10; Gay-Lussao found that, on distilling a dilute solution to one-half, the distillate contained five-sixths of the total HC1O (C. R. 14, 927)"

Another reference suggests twice distilled to further concentrate as needed. My understanding of why this concentrating effect is occurring is that the gaseous anhydride of HClO (Dichlorine Monoxide or Cl2O) is boil off 1st.

The final product upon oxidation of the sulfur should be a very strong acid solution consisting of HCl 3 parts to 1 part H2SO4 (but still low strength with respect to H2SO4 content only). If any of the HClO is converted to HClO3 during the distillation, the product will not only be strongly acidic, but a strong oxiderizer as well.

I think I read calcium hypochlorite powder reacts with sulfur very exothermic, almost explosively. Be careful.

AJKOER - 7-5-2011 at 18:05

Thanks, but I am not reacting sulfur with Ca(OCl)2. I am adding H2CO3 to Ca(OCl)2 to form HClO:

H2CO3 (Aq) + Ca(OCl)2 (s) = CaCO3 (s) +2 HClO (Aq)

In the presence of dissolved CaCl2 (also found in Bleaching Powder), there may be some HCl generated which would react with the HClO to form Cl2. I am only suggesting this reaction since some sources note the generation of Cl2 with H2CO3 on Bleaching Powder (Wikipedia), which would normally require the presence of HCl. In my opinion, this may imply that the following reaction is partially reversible(?). Reason, the CaCO3 is leaving the solution, the dissolving of the CaCl2 is exothermic adding energy, and the CO2 is dissolved (in the normal reverse reaction CO2 is released):

H2CO3 (Aq) + CaCl2 (Aq) <==> CaCO3 (s) + 2 HCl (Aq)

HCl + HClO <==> Cl2 + H2O

However, as the reaction chamber is closed, HClO is eventually formed in any event.

Random - 8-5-2011 at 11:33

You think about making something similar to lead chamber which uses nitrogen dioxide to oxidize so2 formed by sulfur burning? Maybe you could react sulfur dioxide with chlorine in water solution (so you can skip dangerous exothermic hydrolysis step of SO2Cl2 + H2O -> H2SO4 + HCl). Be aware that in water could be exothermic too, also you would be generating 2 toxic gases which form toxic mist of SO2Cl2 in the air when reacting.

woelen - 8-5-2011 at 12:03

SO2Cl2 + H2O is a very tame reaction. I tried this one and it takes several hours before a drop of SO2Cl2 has dissolved in water completely.

Making H2SO4 from SO2 and Cl2 indeed can be useful. In that case first dissolve SO2 in water until no more can be dissolved. Then lead through Cl2 until the liquid starts smelling of Cl2. Then dissolve SO2 again in the same liquid, lead through Cl2 again, et.c. This still is quite cumbersome, but it can be done more easily than the other mechanisms presented here, based on oxidation of sulphur by HOCl.

symboom - 8-5-2011 at 16:27

bleach and sulfur that is interesting i can make 5% bleach easily from my chlorate cell with in an hour at 20 Amp and reaction with vinegar forming sodium acetate and hypochlorous acid the react with sulfur
one problem with that once sulfuric acid is formed it will react with the sodium acetate that you made from the starting reaction making vinegar again the solution will have a mixture of (sodium sulfate, vinegar,and hydrochloric acid)

copper sulfate will work perfectly for sulfuric acid
using electrolysis mechanical pencil led anode and copper cathode

you can also make it using magnesium sulfate (Epsom salt bought at any store next to hydrogen peroxide. i got a pound for $1 ain't bad)
which you need to separate the anode and cathode by a salt bridge.
and i have not tried using a volt meter to see if all has been split into magnesium hydroxide and sulfuric acid the acid will be contaminated with magnesium sulfate but there's no problem for using it to make Nitric acid and Hydrochloric acid

[Edited on 9-5-2011 by symboom]

Chemistry Alchemist - 13-9-2011 at 02:55

Quote: Originally posted by AJKOER

or add distilled water to increase stability of HClO and to aid in crystallization that occurs upon freezing to separate out Sodium Acetate Hydrate (CH3COONa.3H20).

Will all the Sodium acetate crystallize out of the Hypochlorous Acid? id want mostly pure acid so i can make Potassium Chlorate from it

The WiZard is In - 13-9-2011 at 11:35

Quote: Originally posted by AJKOER

Hi:

Waiting on my sulfur to perform the following cheap and simple way to make H2SO4. Comments and suggestions welcomed.

Thirty minutes in the library will often save thirty days in
the laboratory.

Scanned — and you know what that means!

Wilfred Wyrd
Raw Materials for the Manufacture of Sulphuric Acid and the Manufacture of Sulphur Dioxide
Gurney and Jackson
Edinburgh 1923

CHAPTER I

HISTORICAL AND GENERAL NOTES ON THE MANUFACTURE
OF SULPHURIC ACID

History of the Manufacture of Sulphuric Acid.

ACCORDING to Rodwell (Birth of Chemistry) it is very probable
that sulphuric acid was already known to the ancients ; but
usually its first, although indistinct, mention is ascribed to the
Arab Geber, who speaks of the "spirit" which can be expelled
from alum and which possesses solvent powers. Geber is,
however, a mythical personage, and many of his alleged
numerous discoveries have wrongfully crept into the Latin "
translations " of his pretended writings, as proved by Berthelot
and Steinschneider, [1] who show that sulphuric acid was un
-known to the Arabian writers about A.D. 975. Others give the
honour of its discovery to the Persian alchemist Abu-Bekr
-Alrhases, who is said to have died in 940. Vincentius de
Beauvais (about 1250) alludes to it ; and Albertus Magnus
(1193—1280) speaks of a spiritus vitrioli Romani, which can
only have been sulphuric acid ; his " sulphur philosophorum " is
the same thing.

Basil Valentine, who probably lived in the second half of the
fifteenth century, in his Revelation of the Hidden Manipulations,
clearly described its preparation from calcined copperas and
silica, and, in his Triumphal Car of Antimony, its preparation by
burning sulphur with saltpetre ; [2] but he took the two to be
different substances.

Gerhard Dorm us (1570) described its properties accurately;
Libavius (1595) recognised the identity of the acids from
different processes of preparation ; this was done also by
Angelus Sala (1613), who pointed out the fact, which had
sunk into oblivion since Basilius, that sulphuric acid can be
obtained by burning sulphur in moist vessels (of course with
access of air) ; after that time it was prepared by the
apothe¬caries in this way. An essential improvement, the
addition of a little saltpetre, was introduced in 1666 by Nicolas
le Fevre and Nicolas Lémery. This started a sort of manufacture
of vitriol which is said to have been introduced into England by
Cornelius Drebbel ; a quack doctor of the name of Ward first
carried on sulphuric-acid making, on what was then a large
scale, at Richmond, near London, probably a little before 1740.
Ward employed large glass vessels up to 66 gallons capacity,
which stood in two rows in a sand-bath, and which were
provided with horizontally projecting necks ; at the bottom they
contained a little water. In each neck there was placed an
earthenware pot, and on this a small red-hot iron dish, into
which a mixture of one part saltpetre and eight parts of
brimstone was put. The neck of the bottle was then closed with
a wooden plug until the combustion was finished. Fresh air was
allowed to enter the vessel, and the operation was repeated till
the acid had become strong enough to pay for concentrating in
glass retorts.

Ward called the product " oil of vitriol made by the bell "
(already Basil Valentine had used the expression " per
campanam " in this sense), in order to distinguish the spirit of
vitriol made from brimstone from that distilled from sulphate of
iron, the latter having been already before Ward's time made
on a kind of manufacturing scale in England. Ward's process,
troublesome as it was, reduced the price of the acid from 2s.
6d. per oz. (the price of the acid from copperas or from burning
brimstone under a moist glass jar) to 2s. per lb.

An extremely important improvement in this process was the
introduction of the lead chambers, which by general consent is
ascribed to Roebuck of Birmingham, [3] who in 1746 erected
such a chamber 6 ft. square, and in 1749, in partnership with
Mr Garbett, built a factory with lead chambers at Prestonpans
in Scotland, in order to supply acid for bleaching linen. The
mixture of brimstone and saltpetre in the pro-portion employed
by Ward was put into small iron wagons.........

[1] Cf: Lippmann, Z. angew. Chem., 1901, p. 646.
[2] Kopp, Gesdzichle der Czernie, 3, p.303
[3] Gutmann, f, Spc, Client. Incl., 1901, p. 5.

AJKOER - 16-9-2011 at 10:38

In place of HClO, one could theoretically employ the gaseous anhydride of HClO, namely Cl2O. One preparation method (untried by myself) is by passing Cl2 and steam over a fresh precipitate of CaCO3:

2 Cl2 (g) + H2O (g) + CaCO3 (s) (as a fresh precipitate) --> CO2 (g) + H20 (g) + CaCl2 (s) + Cl2O (g)

Then react the dilute Cl2O gas and steam with Sulfur (Caution: possible very violent reaction, see reference below):

Cl2O + 2 H2O + S --> H2SO3 + 2 HCl

Note, this reaction consumes water so the reactant products may be strong (and caustic).

On the possible dangerous reaction of Sulfur and even dilute Cl2O:

"Sulphur, phosphorus, carbon compounds, and the alkali metals react violently with the gas, taking fire with explosive decomposition."

Source: http://www.freefictionbooks.org/books/e/12896-encyclopaedia-...

As such, one could criticize this production process for H2SO4 as being potentially too dangerous/reactive (but certainly not feeble as suggested for strong HClO, although this characterization not be accurate) given the tendency of Dichlorine Mono-oxide to explode with exposure to shock, light, heat and certain organic compounds (like Sulfur).

Gui316 - 19-9-2011 at 02:48

hocl can also be prepared using calcium hypochlorite, right? if so , it would yield a higher concentration of it i think.