Ferric persulfate

Synonyms ferric sulfate ferric persulfate ferric sesquisulfate... 

The most suitable oxidizing agent is potassium ferricyanide, but ferric chloride, hydrogen peroxide ia the presence of ferrous salts, ammonium persulfate, lead dioxide, lead tetraacetate or chromate, or silver and cupric salts may be useful. Water mixed, eg, with methanol, dimethylformamide, or glycol ethers, is employed as reaction medium. 

Copper etchants do not directly influence the electroless plating process, but are used merely to remove unwanted copper, and should not affect the deposit properties. The costs of waste treatment and disposal have led to disuse of throw-away systems such as chromic—sulfuric acid, ferric chloride, and ammonium persulfate. Newer types of regenerable etchants include cupric chloride, stabilized peroxide, and proprietary ammoniacal etchant baths. 

Asghar and Khan [33] modified the method by adding K2S2O8 (potassium persulfate) in an acetate buffer at pH 5.6 as the initiator of DMPD". They abandoned ferric chloride, due to the presence of metal ions in the analysed material which could - as a result of the Fenton Reaction... 

The first report of the polymerization of tetrafluoroethylene was by Plunkett in 1941, who had a cylinder of tetrafluoroethylene cut open to see why the expected amount of gas was not released when the valve was opened. His perspicacity led to the discovery of an inert, white, opaque solid with a waxy feel. Various methods of polymerization were tried after the adventitious discovery and the preferred methods for polymerization now involve aqueous media and super-atmospheric pressures. Suitable initiators (Hanford and Joyce) include ammonium, sodium, or potassium persulfate, hydrogen peroxide, oxygen, and some organic peroxy compounds. Oxidation-reduction initiation systems involving the use of persulfate with either ferrous ion or bisulfite or the use of bisulfite with ferric ion are also useful and have been discussed by Berry and Peterson. 

Acid solutions, excluding hydrochloric e.g., phosphoric, sulhiric, most conditions, many organics Neutral solutions, e.g., many non oxidizing salt solutions, chlorides, sulfates Caustic and mild alkalies, excluding ammonium hydroxide Neutral or alkaline solutions, e.g, persulfates, peroxides, chromates Pitting media, acid ferric chloride solutions Freshwater supplies Seawater Steam Furnace gases with incidental sulfur content ... 

Recovery tests were run on samples of various industrial waters by the above proposed atomic absorption-solvent extraction procedure. However before extraction, all samples were acidified with I ml. concentrated hydrochloric acid per 100 ml. sample and boiled for five minutes to dissolve precipitated metals. The samples were then cooled and filtered to remove any remaining particulate matter which could clog the atomizer. For the determination of iron, 0.1 gram potassium persulfate was added in addition to the acid and then boiled to oxidize ferrous iron to the ferric state. The values shown in Table III are typical of the results that can be expected. 

Persulfate ion initiator (e.g., fromKjSjOg) reacts with a reducing agent such as a bisulfite ion (e.g., from NaHSOj) to produce radicals for redox initiation (Equations 2.5 and 2.6). Ferric ion may also be used as a source of radicals (Equation 2.7). Other redox reactions involve the use of alkyl hydroxides and a reducing agent such as ferrous ion (Equation 2.8). 

Besides oxygen, solutions can contain other oxidizing species, such as peroxide, persulfate, nitrate, and ferric ions. The reversible potential associated with the reduction of these species will depend on their concentration. 

The kinetics of aqueous dispersion polymerization differ very little from acrylonitrile bulk or emulsion polymerization. Redox initiation is normally used in commercial production of polymers for acrylic fibers. This type of initiator can generate free radicals in an aqueous medium efficiently at relatively low temperatures. The most common redox system consists of ammonium or potassium persulfate (oxidizer), sodium bisulfite (reducing agent), and ferric or ferrous iron (catalyst). This system gives the added benefit of supplying dye sites for the fiber. 

This redox system works at pH levels in the range 2-4, where the bisulfite iron predominates. Two main reactions account for radical production. These are the oxidation of ferrous iron by persulfate, and the reduction of ferric iron by SO2 in the bisulfite form. 

CAS 10028-22-5 EINECS/ELINCS 233-072-9 Synonyms Ferric sesquisulfate Ferric trisulfate Ferrisulfate Iron persulfate Iron sulfate... 

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