Solid permanganate production

The solid wastes from permanganate production contain unreacted ore, precipitated MnOj as well as potassium (K) and calcium (Ca) salts. The treatment and disposal of wastes include the extraction of residual manganese, uses as an absorbent for air pollutants, as a micronutrient additive for fertilizers, as building materials, and as deposits in landfills (Reidies 2003). 

Methylated spirit contains, in addition to ethyl and methyl alcohols, water, fusel-oil, acetaldehyde, and acetone. It may be freed from aldehyde by boiling with a—3 per cent, solid caustic potash on the water-bath with an upright condenser for one hour, or if larger quantities are employed, a tin bottle is preferable, which is heated directly over a small flame (see Fig. 38). It is then distilled with the apparatus shown in Fig. 39. The bottle is here surmounted with a T-piece holding a thermometer. The distillation is stopped when most of the spirit has distilled and the thermometer indicates 80°. A further purification may be effected by adding a little powdered permanganate of potash and by a second distillation, but this is rarely necessary. The same method of purification may be applied to over-proof spirit, which will henceforth be called spirit as distinguished from the purified product or absolute alcohol. 

A solution of 11.2 g of potassium permanganate in 100 ml of warm water was added drop-wise to a well stirred solution of 10 g of 2-(4-chlorophenyl)-3-methyl-4-metathiazanone in 50 ml of glacial acetic acid. The temperature was kept below 30°C with external cooling. An aqueous sodium bisulfite solution was then added to remove the manganese dioxide. The thick whitish oil which separated was taken up in chloroform and the extract was washed with water. Removal of the chloroform by distillation in vacuo yielded an oily residue which solidified. The solid was recrystallized from isopropyl alcohol to give 5 g of the product, 2-(4-chlorophenyl)-3-methyl-4-metathiazanone-1,1-dioxide, MP 116.2° to 118.6°C (corr.). 

The products of the reaction between bromide ions and permanganate ions, Mn04, in basic aqueous solution are solid manganese(IV) oxide, MnO>, and bromate ions. Balance the net ionic equation for the reaction. 

A. 2-Methyl-2-nitropro]f)ane. To a well-stirred suspension of 650 g. (4.11 moles) of potassium permanganate in 3 1. of water, contained in a 5-1. three-necked flask fitted with a reflux condenser, a mechanical stirrer, a thermometer, and a 250-ml. dropping funnel, is added dropwise and with stirring over a 10-minute period, 100 g. (1.37 moles) of i-butylamine (Note 1). When the addition is complete, the reaction mixture is heated to 55° over a period of approximately 2 hours, and then the reaction mixture is maintained at 55° with continuous stirring for 3 hours. The dropping funnel and reflux condenser are replaced by a stopper and a still head fitted for steam distillation and the product is steam distilled from the reaction mixture (Note 2). The liquid product is separated from the denser water layer and then diluted with 250 ml. of ether and washed successively with two 50-ml. portions of aqueous 2M hydrochloric acid and with 50 ml. of water. After the ethereal solution has been dried over anhydrous magnesium sulfate, the solution is fractionally distilled at atmospheric pressure to remove the ether. The residual crude product (Note 3) amounts to 106-128 g. and is sufficiently pure for use in the next step. In a typical run, distillation of 124 g. of the crude product afforded 110 g. (78%) of the pure 2-methyl-2-nitrobutane as a colorless liquid, b.p. 127-128°, d 1.3992. The material slowly solidifies on standing to a waxy solid, m.p. 25-26° (Note 4). 

It is also possible to use hydrazine hydrate alone as a monergol owing to its high heat of decomposition. Energy and gaseous products are provided by decomposition induced by permanganates, commonly used in the solid form. 

Precolumn derivatization with a solid-phase derivatizing precolumn has also been reported. Xie et al. (43) applied polymeric permanganate oxidations of alcohols and aldehydes for the production of UV-absorb-ing species. 

To avoid the production of sulphur by the reduction of potassium permanganate by hydrogen sulphide in systematic qualitative analysis, the solution may be reduced with formaldehyde solution, or the solid substance may be boiled with concentrated hydrochloric acid. The use of sulphur dioxide is not recommended (see footnote in connection with Chromates, Section IV.33, reaction 5). 

In a typical experiment, a solution of 4-formyl-2,2-dimethy-l//-1,5-benzodiazepine (0.036 mol) in THF (300 mL) was added in small portions to a solution of potassium permanganate (0.063 mol) in water (100 mL) over a period of 3.5 h. (Addition of solid KMn04 to neat THF could produce an explosive mixture, and should therefore be avoided) During the addition, the mixttue was allowed to warm to about 40 C. The mixture was then filtered to remove manganese dioxide and the filtrate was concentrated and extracted with diethyl ether. After drying, the extract was concentrated and the resulting product crystallized from diisopropyl ether. The overall yield was 7 g (79%). 

For the ozonolysis of linear alkenes only alk-l-encs should be used to avoid product mixtures as the resulting formaldehyde or formic acid are readily separated. This type of reaction is also a successful method for the preparation of perfluorinated carboxylic acids.The advantage over the oxidation with potassium permanganate is that the process does not form solid byproducts which are diflicult to separate. A disadvantage of this procedure is the fact that two reaction steps arc needed to obtain the required product. 

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