Manganese method

NIOSH. 1984a. Total manganese-method 7200. In NIOSH manual of analytical methods. 3rd ed. Vol. 

The manganese method has a repeatability of 0.24 mg/kg. At 12.0 mg/kg Mn level, the precision of the method is +/- 1.16 mg/kg. Diesel fuel was diluted 100-fold to keep the method consistent detection limits and precision could be better for diesel at lower dilutions since diesel is not as volatile as gasoline. 

We used four different methods for measuring the distribution of fission-producing neutrons. These methods will be described in this section. The first will be called the Wide Sample Physical Method, the second the Narrow Sample Physical Method, the third the Manganese Method, and the fourth the Chemical Method. 

On the industrial scale oxygen is obtained by the fractional distillation of air. A common laboratory method for the preparation of oxygen is by the decomposition of hydrogen peroxide. H Oj, a reaction catalysed by manganese(IV) oxide ... 

Alternatively a mixture of almost any solid chloride and manganese-(IV) oxide will yield chlorine when warmed with concentrated sulphuric acid. These are the most common laboratory methods but there are many others. 

Iodine is rarely prepared in the laboratory the method used is the oxidation of an iodide by manganese(IV) oxide and sulphuric acid, for example with sodium iodide ... 

The principal ores of zinc are sphalerite (sulfide), smithsonite (carbonate), calamine (silicate), and franklinite (zine, manganese, iron oxide). One method of zinc extraction involves roasting its ores to form the oxide and reducing the oxide with coal or carbon, with subsequent distillation of the metal. 

The amount of iron and manganese in an alloy can be determined by precipitating the metals with 8-hydroxyquinoline, C9H7NO. After weighing the mixed precipitate, the precipitate is dissolved and the amount of 8-hydroxyquinoline determined by another method. In a typical analysis, a 127.3-mg sample of an alloy containing iron, manganese, and other metals was dissolved in acid and... 

Mutagenic PGR. More recently, methods have been developed to use the PGR reaction to randomly mutagenize a defined sequence (25). The Taq polymerase used in PGR misincorporates nucleotides in a random fashion if manganese dichloride [7773-01 -5] MnGl2, is included in the reaction buffer during PGR. The Hbrary of mutagenized PGR products can be screened for the desired phenotype. 

A thkd method utilizes cooxidation of an organic promoter with manganese or cobalt-ion catalysis. A process using methyl ethyl ketone (248,252,265—270) was commercialized by Mobil but discontinued in 1973 (263,264). Other promoters include acetaldehyde (248,271—273), paraldehyde (248,274), various hydrocarbons such as butane (270,275), and others. Other types of reported activators include peracetic acid (276) and ozone (277), and very high concentrations of cobalt catalyst (2,248,278). 

The yield of hydroquinone is 85 to 90% based on aniline. The process is mainly a batch process where significant amounts of soHds must be handled (manganese dioxide as well as metal iron finely divided). However, the principal drawback of this process resides in the massive coproduction of mineral products such as manganese sulfate, ammonium sulfate, or iron oxides which are environmentally not friendly. Even though purified manganese sulfate is used in the agricultural field, few solutions have been developed to dispose of this unsuitable coproduct. Such methods include MnSO reoxidation to MnO (1), or MnSO electrochemical reduction to metal manganese (2). None of these methods has found appHcations on an industrial scale. In addition, since 1980, few innovative studies have been pubUshed on this process (3). 

The iodide method can also be appHed to the analysis of other manganese species, but mixtures of permanganate, manganate, and MnO interfere with one another in the iodometric method. 

A detailed review of the methods for deterrnination of low manganese concentration in water and waste is available (179). A review on the speciation of Mn in fresh waters has been reported (180). Reviews for the chemical analysis of Mn in seawater, soil and plants, and air are presented in References 181, 182, and 183, respectively. 

H. W. Fishbum, Jr., and W. E. DiU, Jr., "A Method for the Semiquantitative Analysis and Identification of Mixed Phases of Manganese Dioxide," paper presented at the Power Sources Conference, Atlantic City, N.J., May 10, 1961. 

European matches, mosdy of brown or black tips, are basically identical with U.S. matches ia their formulations, except that they contain ia addition red iron oxide or manganese dioxide of pigment grade ia the match heads (2). Match materials, testing methods, and related matters have been reviewed (7,8). 

Diphenylmethane Base Method. In this method, the central carbon atom is derived from formaldehyde, which condenses with two moles of an arylamine to give a substituted diphenylmethane derivative. The methane base is oxidized with lead dioxide or manganese dioxide to the benzhydrol derivative. The reactive hydrols condense fairly easily with arylamines, sulfonated arylamines, and sulfonated naphthalenes. The resulting leuco base is oxidized in the presence of acid (Fig. 4). 

Although an inherently more efficient process, the direct chemical oxidation of 3-methylpyridine does not have the same commercial significance as the oxidation of 2-methyl-5-ethylpyridine. Liquid-phase oxidation procedures are typically used (5). A Japanese patent describes a procedure that uses no solvent and avoids the use of acetic acid (6). In this procedure, 3-methylpyridine is combined with cobalt acetate, manganese acetate and aqueous hydrobromic acid in an autoclave. The mixture is pressurized to 101.3 kPa (100 atm) with air and allowed to react at 210°C. At a 32% conversion of the picoline, 19% of the acid was obtained. Electrochemical methods have also been described (7). 

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