Analysis total soluble salt

Analysis always necessitates determinations of the sugar (saccharose) and of the soluble salts, since from these is calculated the yield (rendement) on refining. Determinations may also be made of the invert sugar, water, non-sugar and, in some cases, raffinose, total ash and alkalinity sometimes sulphurous anhydride is tested for, but the colour is seldom measured. 

Note The following Requirements and Tests apply to the Pectins as supplied, whether standardized or not, except for specifications covering amide substitution and the weight percent of total galacturonic acid in the Pectin component, in which cases the test procedures include provisions for removing the sugars and soluble salts before analysis of the Pectin component. 

The key treatment system properties to consider in carrying out this analysis are (1) whether the effluent is acidic or alkaline, (2) the desired final pH, (3) the presence of ions forming poorly soluble salts with the reagent, and (4) the total acid load. 

Chemical analysis. Silica, stabilizing base, carbon including carbon dioxide, organic carbon, soluble salts of alkali metals, total solids and non-siliceous ash, metals including aluminum and iron. 

Aqueous and nonaqueous samples must be digested with an acid before their analysis by atomic absorption or atomic emission spectrophotometry. The metals and their salts present in the sample are converted into their nitrates due to the fact that the nitrates of all metals are soluble in water. Therefore, concentrated nitric acid by itself or in conjunction with hydrochloric acid, sulfuric acid, perchloric acid, or hydrofluoric acid is used in sample digestion for the determination of total metals. Nitric acid alone is, however, adequate for digestion of most metals. Table 1.8.1 lists the combinations of acids that may be helpful in sample digestion. 

The total yield of the crude precipitation obtained in the above manner comprising about 1 kg is then dissolved in chloroform so as to form a 15% solution of a crude penicillin salt. To the filtered chloroform solution is added ethyl acetate slowly and with agitation until the solution becomes turbid as crystallization begins. Thereafter crystallization is allowed to proceed undisturbed for about 30-60 minutes in a cold room having a temperature of about 5°C. Sufficient ethyl acetate is slowly added to provide a final concentration of about 50% ethyl acetate and the mixture is allowed to stand in the cold room for one hour to complete crystallization. The precipitate is filtered and washed with about 750 ml of ethyl acetate and thereafter washed with the same volume of ether. The crystals are dried in vacuo and a yield of about 900 g of N,N -bis-(dehydroabietyl)-ethylenediamine-dipenicillin G is obtained. The penicillin product melts with decomposition at a temperature of 170°C to 172°C on a Kofler hot stage. Solubility analysis of the product shows the product to be 95.3% pure. 

In the inductively coupled argon plasma emission spectrometer method, nickel, iron, and vanadium content of gas oil samples in the range from 0.1 to 100 mg/kg. Thus a 10-g sample of gas oil is charred with sulfuric acid and subsequently combusted to leave the ash residue. The resulting sulfates are then converted to their corresponding chloride salts to ensure complete solubility. A barium internal standard is added to the sample before analysis. In addition, the use of the ICAP method for the analysis of nickel, vanadium, and iron present counteracts the two basic issues arising from metals analysis. The most serious issue is the fact that these metals are partly or totally in the form of volatile, chemically stable porphyrin complexes and extreme conditions are needed to destroy the complexes without losing the metal through volatilization of the complex. The... 

The precipitation of chloride and, if present, dissolved bromide and iodide as the total of dissolved halide ions by silver salts as low-solubility silver halides is also not only used for concentrating traces of bromide and iodide for example, but also for gravimetric analysis, as a method of calibration. Bromide and iodide should then be determined separately (Section 3.2) and subtracted from the total of the precipitated halides. Reliable results are then obtained even at high concentrations. 

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