Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Ferrous tartarate
Boffis
International Hazard
*****




Posts: 1879
Registered: 1-5-2011
Member Is Offline

Mood: No Mood

[*] posted on 20-10-2019 at 02:09
Ferrous tartarate


Has anyone ever tried to prepare ferrous tartarate? I want some as a catalyst for a Fenton type oxidation of tartaric acid so to keep the unnecessary ions to a minimum I decided to try dissolving iron powder in tartaric acid. In one of the papers I read this was described briefly but I can't find it again.

Anyhow I added 4g (an excess) of fine iron fillings to 10g of lab grade tartaric acid in 100ml of water and gently warmed. To my surprise a vigorous reaction set in and copious amounts of unpleasant smelling hydrogen were evolved. I left it fizzing away, when I returned 30minutes later the contents of the beaker had set into a semi-solid pale bluish grey custard like mass. Warming only makes it glug as the hydrogen is evoved more quickly and the bubbles unit before reaching the surface.

When the reaction appeared to have ceased and most of the iron dissolved I diluted the thick creamy mass to 300ml with water, heated to boiling and filtered hot. Nothing has crystallised from the filtrate and it is quite colourless. The filter cake is drying but is pale bluish grey.

Is ferrous tartarate insoluble? or have I reduced the tartaric to something else. I found a reference to the preparation of ferrous tartarate 2,5 hydrate but its in a very obscure Czech journal not available online and another that states that it is a red solid.

Anyone any helpful experience?

Just done the next obvious experiment and mixed 10g of tartaric acid in 100ml of water carefully neutralised with 10M NaOH solution and then mexed it with 18.3g of ferrous sulphate dissolved in 100ml of water plus 2ml of 32% sulphuric acid and a little iron powder to ensure that any ferric iron was reduced. The latter solution was filtered before mixing.

Initially the solution turn greenish yellow then very slowly a pale precipitate has started to form. What worries me about this technique is the possible formation of a sodium tartaratoferrate II complex while the tartarate ion concnetration is still high and then only part of the iron is turned into tartarate.

The crystalline ppt was filtered of and dried to give a pale yellow green solid that is sparingly soluble in the cold but more so in hot water.

[Edited on 20-10-2019 by Boffis]

[Edited on 20-10-2019 by Boffis]
View user's profile View All Posts By User
Waffles SS
Fighter
****




Posts: 998
Registered: 7-12-2009
Member Is Offline


[*] posted on 20-10-2019 at 11:56


All possible way for synthesis ferrous tartarate

Attachment: Ferrous tartarate.pdf (82kB)
This file has been downloaded 756 times

[Edited on 21-10-2019 by Waffles SS]




Chemistry = Chem + is + Try
View user's profile View All Posts By User
Boffis
International Hazard
*****




Posts: 1879
Registered: 1-5-2011
Member Is Offline

Mood: No Mood

[*] posted on 21-10-2019 at 02:13


Many thanks Waffles. Interestingly I have already used two of the methods and got what appear to be different product. However, I have now found the original paper by Fenton (Trans. Chem. Soc. 1894 v65 p899). It was Fenton's original paper on the catalytic use of ferrous iron with hydrogen peroxide.

Interestingly he suggests the use of only 1/250 M equivalence of iron is dissolved in the tartaric acid or ferrous tartrate precipitates. So clearly ferrous tartrate (or is it tartarate?) is sparingly soluble and this is my observation too. When pure and completely unoxidised it is probably a pale bluish grey but the crystalline material prepared by double decomposition is a pale greenish grey.

Some photographs of my experiments:

Stitch1.jpg - 66kB
The bluish grey reaction mixture from iron filings in tartaric acid

Stitch2.jpg - 63kB
The solution that results from ferrous sulphate and sodium tartarate, on the right, starting the precipitate ferrous tartarate

Stitch3.jpg - 81kB
Left; the fresh filter cake from the iron method Right; the fresh crystalline ppt from the ferrous sulphate method
View user's profile View All Posts By User
pneumatician
Hazard to Others
***




Posts: 412
Registered: 27-5-2013
Location: Magonia
Member Is Offline

Mood: ■■■■■■■■■■ INRI ■■■■■■■■■■ ** Igne Natura Renovatur Integra **

[*] posted on 13-4-2020 at 09:44


hi, yesterday I make this too. With a saturated distilled water of tartaric acid (TA). I put 15 gm of iron in fillings. Soon the mix get a lime yellow-green color. I raised temp under boiling and a lot of fizzing but not too much unplesand odor.

The pics are after cooling overnight. The iron displaced TA from water? you can see 3 layers, iron undisolved at bottom, a milky layer and the yellow green water.

Have you acces to the docs? waht say about of the method of boiling??



PTDC0010.JPG - 74kB

[Edited on 13-4-2020 by pneumatician]

PTDC0004.JPG - 202kB

[Edited on 13-4-2020 by pneumatician]

PTDC0009.JPG - 121kB
View user's profile View All Posts By User

  Go To Top