Sodium persulphate

However, if an oxidising agent (fuming nitric acid or sodium persulphate) is present to destroy the hydrogen iodide as it is formed, the equilibrium is displaced and the iodo compound may be conveniently prepared, for example ... 

Finally, sodium persulphate is added in order to weaken the fibre. Before the cotton is spun to a thread, this thread is reinforced with a layer of cellulose to reduce the incidence of failures during the spinning process. Obviously, the cellulose layer will have to be removed later, and this can be achieved either by means of enzymes in a process preceding the bleaching, or with sodium persulphate simultaneously with the bleaching process. 

Scheme 7 a Reaction mechanism when sodium persulphate was used as hydroxylating agent for the polymer (P-H). b Decomposition of hydroxylated polymer P-OH at the surface, in the presence of ceric ammonium nitrate generated alkoxy radicals (P-0 ) which initiated the grafting... 

When sodium persulphate was used as hydroxylating agent for the polymer (P-H), the reaction underwent the mechanism shown in Scheme 7a. 

Sodium persulphate, Na2S208.—The persulphate is formed in solution by the electrolysis of a concentrated aqueous solution of sodium sulphate at low temperature and high current-density. The solid persulphate can be obtained by double decomposition of ammonium persulphate and sodium carbonate either in the solid state or in concentrated solution, the crystalline salt being isolated from the solution either by addition of alcohol or by concentration at reduced pressure.15 When dry and protected from sunlight, it keeps almost unchanged for years.16... 

Sheclucr ami K. U. Kaplan [I. Hi nhtainetl Wr-cliniiroafkarios by llic oxidation ot primary and secondary alkanes tin alkaline medium) will) sodium persulphate (40)... 

In the pad-steam process, the fabric is padded with a solution containing 70 g/1 caustic soda, 3 g/1 sodium persulphate and 10 g/1 non-ionic detergent at 40°C with a wet pick-up of about 80% and then the fabric is steamed for 12 min at 102 C. The fabric is then washed thoroughly in an open soaper with a temperature of about 98 C in the first and second, 80°C in the third and 60 and 50 C in the fourth and fifth compartments respectively. 

To a solution containing 2.975 g of sodium persulphate, NaiSjOi, is added an excess of potusium iodide solution. A reaction occurs, in which sulphate ions are formed and 3.175g of iodine are formed, Deduce the equation for the reaction,... 

Persulphates are those compounds based on the species in which the sulphur exists in its highest state of oxidation, sulphur(VII), including sodium persulphate. They are strong oxidizers used as bleaches. 

The largest of these processes remains those for ammonium and sodium persulphate and there are several plants operating on the 2000—10000 ton yr scale. The process involves the oxidation of the sulphate in a sulphuric acid medium at a Pt-based anode and the medium must be free of heavy-metal ions which catalyse the decomposition of persulphate. The current density is high, about 1 A cm" and the current efficiency 60—80%. Two cell technologies are used one uses a cell with an asbestos diaphragm while the other is an undivided concentric tube cell. To avoid reduction of the persulphate at the cathode, the conversion per pass is kept low and the persulphate is crystallized between passes through the cell. 

Phenytoin and related xenobiotics can be bioactivated by embryonic prostaglandin H synthase to a teratogenic free radical intermediate. Parman et al. (1998) evaluated the mechanism of free radical formation using photolytic oxidation with sodium persulphate and by electron paramagnetic resonance spectrometry. Incubation of 2 -deoxyguano-sine with phenytoin and prostaglandin H synthase-1 resulted in a 5-fold increase in the oxidation to 8-hydroxy-2 -deoxyguanosine. 

A number of etchants are in use, depending upon the nature of the process and, to an extent, peisona] preferenoe or tradition. These include (1) afnmORium persulphate (2) sodium persulphate (3) potassium peroxysulphate (4) cupric chloride (5) FeClj (6) HjCrO (7) ammoniiN at chlorite and (8) hydrogen... 

Oxidation of pent-4-en-l-ol by sodium persulphate and silver ion in the presence of protonated lepidine leads to (1) and (2) in a 9 1 ratio (Scheme 2). 2-Allyloxyethanol, however, gives (3) by preliminary /3-fission to an alkoxyalkyl radical before attack on the protonated lepidine. ... 

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