JPS59111920A - Oxidation of thallium (i) to thallium (iii) - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the oxidation of primary thallium compounds to secondary thallium compounds.

The oxythallization (α) reaction is well known and described in detail in the literature. Those reactions are directed to inorganic thallium (I) to unsaturated organic substances such as olefins, acetylenes, ketones or aldehydes.
II) Accompanied by addition of salt. U.S. Patent No. 3,641,067
No. 1, he fully discloses the use of thallium carboxylates, such as thallium acetate, to oxidize olefins in acid solutions to the corresponding epoxides. In order to put this process into practical use, it is necessary to provide an economical method for oxidizing thallium(1)' to thallium(III) to allow thallium valence klJ cycles.

MacLeαn et al., in U.S. Pat.
We propose electrolytic oxidation to I) and the use of the acidic solution generated therein for olefin oxidation. The use of molecular oxygen is described in U.S. Pat. No. 3,399,956: 4°113.75.
No. 6: No. 4,115,419 and No. 4,192.81
It is proposed in No. 4. When using molecular oxygen,
In general, it is necessary to use additional catalysts and promoters, and, from an economical point of view, it is necessary to use all high pressure oxygen. Moreover, high alloy equipment is usually required in molecular oxygen processes due to the full use of acidic media in the presence of oxygen.

U.S. Patent Nos. 4,115,419 and 4,115,4
No. 21 is an acidic solution of thallium (1) thallium (■) (
All this suggests the need for the use of organic hydroperoxides for the oxidation (to acidic solutions) and, in that case, also for the use of Group I noble metal compounds as catalysts. Organic hydroperoxide processes require expensive noble metal catalysts and
The problem is the problem of disposal of by-products generated from hydroperoxides.

US Pat. No. 4,226,790 suggests the use of organic peracids for the oxidation of thallium (1) to thallium (■). This process not only has the disadvantage of producing undesirable by-products, namely carboxylic acids, which must be recovered, but also produces very expensive ruthenium or (reaction)
It also has the disadvantage of using a catalyst such as manganese which must be separated from the solution.

Frill et al. in U.S. Pat. No. 3,436,409 describe how thallium (III) can be extracted using known techniques, such as by chemical or electrolytic methods, such as using sonic reactions with molecular oxygen, hydrogen peroxide, and the like. ) states that it can be played back. But I
li l 1 et al. do not disclose how hydrogen peroxide can be utilized for this purpose. This reference to the oxidation of hydrogen peroxide to t-thallium (In) is probably due to Zeit, An, org, Chem,
, vol. 48, pp. 427-440 (1906).
It is based on the literature by B.B.T.

The reaction between elemental thallium and its compounds using hydrogen peroxide was first described in 1864 by SchEpnlygix, who showed that hydrogen peroxide first oxidized thallium oxide to higher oxides and then Rabe states that he observed that the reduction produced an oxygen sound, and that the oxygen reacted with higher oxides while releasing all of the oxygen. 100 hydrogen peroxide
Chocolate in a strong alkaline solution when using an excess of
fRabe has discovered that it is possible to produce oxidized secondary chloride of Burakun. The reaction yield based on thallium was 98% for 4% potassium hydroxide solution (71H13,8): 2-'A% potassium hydroxide solution (p
With HxO,3), the thallium yield dropped to 81%.

The ability of hydrogen peroxide to oxidize to thallium(III) with 10 or more 7)H completely explains the extremely low solubility of thallium(III) hydroxide (a solubility product of 10-53). I can do it. December 1982
In a co-filed American patent application, Ser.

Dipersulfate ion, also known as belloxonisulfate ion, is known as a strong oxidizing agent that works by a different mechanism than hydrogen peroxide. The reaction mechanism is that TlC1) of Wooden et al.
Oxidation reaction of I Cm')"-: Part 1 Reaction rate and mechanism in aqueous solution" Bu, LL, Chern.

Sac, Japcmp Volume 53 (1980).

The reaction in 0.01 M perchloric acid (pH 2) was very slow, and only 60 units of thallium CD were converted in 149 hours, resulting in two sulfuric acid (salt)-free products due to thermal decomposition of dipersulfate ions. Mokuzai et al. report that this is a chain reaction that is the initial stage of radical generation.

Unlike both persulfate ions and hydrogen peroxide, -persulfate ions have the effect of converting thallium (1) to t-thallium (IID) over a wide range and with high conversion efficiency. It was discovered that

For those skilled in the art, for example, U.S. Pat. No. 4,049,78
Persulfate ions can be supplied either by a preferred method such as reacting hydrogen peroxide with sulfuric acid to produce total monopersulfuric acid (Carrow's acid) as taught in No. 6, or by using a persulfate ion. That is clear.

Thallium(I) using dipersulfate ion
The conversion rate to II) is almost quantitative at pH 15;
Below 72H5, it falls below 50%. - With persulfate ions all around, the conversion is essentially quantitative even when the pH is lowered to 1, at which - persulfate rapidly hydrolyzes to hydrogen peroxide and sulfuric acid. −
Oxidation of thallium(1) by persulfate ions does not require a catalyst.

Preferred embodiments of the method will become clear to those skilled in the art from the following non-limiting examples.

Example 1゜10 Mi+)%k(D evening IJ Ram (1), 2.524
f (7) Tl 2So, dissolved in 100 - of water. pH using 18M sulfuric acid and 10M potassium hydroxide
k was adjusted to the desired value and maintained. A stoichiometric amount of Caro's acid was added. The total conversion to thallium (Ill) was then measured. The results are shown in Table 1.

Experiments 2 and 3 were not exposed to the atmosphere, but were connected to a gas bilulet to allow for the possibility of oxidation of the thallium by oxygen from the atmosphere.

Comparative example 1° 10 mmol thallium(1), 2.5242 Tl2
SO4 total 100- dissolved in water. 18M sulfuric acid and 10M
The pH was adjusted to and maintained at the desired value using IJ hydroxide. Stoichiometric ammonium persulfate 2.28
Added 25'. After 4 hours, the conversion to thallium(III) was measured. The results are shown in Table 2.

In the even-numbered experiments, the flask was connected to a gas zeulet without being exposed to the atmosphere, and thallium (I) was absorbed by the oxygen in the air.
) was eliminated from the possibility of being oxidized to thallium (IID).

Table 1 p for aqueous oxidation of thallium CD using Caro's acid
Effect of H 10 15.00 25. υ
2%j%J,6 (Note) Experiments 2 and 3 were isolated from the surrounding atmosphere using a gas burette to eliminate oxidation by 02.

*Initial plI of 9.0 was made to go down to 2.5.

Table 2 Effect of 7) II on the aqueous oxidation of ammonium persulfate and thallium (I) in an aqueous solution 7) H Chi Chi 1 on the atmosphere
2 97,. 1 2.9
Yes 2253.047.0 No 3, 5 55.1 44.9
'f' f4558.641.4 No 5 8 34.9 65.1
Yes 6843.753.3 No 7 12 21.2 78.8
M81221.871.4 No 9 15 10.3 89.7
10150.0100.0 Innocence - From the examples and comparative examples, it can be seen that the oxidation of thallium (1) to thallium (1) by -persulfate ions does not depend on pH in the pH range of 2 to 15. 7) I
It is known that when the molecular weight is lower than -12, monopersulfuric acid rapidly hydrolyzes to form hydrogen peroxide and sulfuric acid.

Patent applicant: FMC Corporation
1, -1 Patent attorney Takehiko Saito r'” -3 (
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Claims (1)

[Claims] p II k p of thallium (1) aqueous solution H2 to 1
of thallium (1) in an aqueous solution consisting of adjusting between 5 and 5 and adding thereto a monopersulfate compound.
l) Method of oxidation to l).