Analysis sulfate content

An analysis of alcohol and alcohol ether sulfates should determine the anionic active matter, the unsulfated matter, the inorganic sulfate content, the chloride content, and water. Other more precise analysis must determine the alkyl chain distribution of the alcohol and in the case of alcohol ether sulfates the number of ethoxy groups and its distribution, as well as other more specialized determinations, such as the content of 1,4-dioxane and other impurities. 

The complete analysis of alcohol sulfates is described in the Standard Methods of the International Organization of Standards (ISO) [200] and of the American Society for Testing and Materials (ASTM) [201]. These methods describe the analysis of inorganic sulfate content, chloride content, unsulfated matter, and water as well as other analytical values. Other ISO standards describe the analysis of sodium secondary alkyl sulfates [202], determination of pH [203], determination of water content [204,205], chlorides [206], total active matter in sul fated ethoxylated alcohols and alkylphenols [207], mean relative molecular mass in sulfated ethoxylated alcohols and alkylphenols [208], sulfate content... 

Wil Kastning of the Nebraska State Agriculture Laboratory filters barium sulfate precipitates using filtering crucibles and a vacuum system while performing a gravimetric analysis of fertilizers for sulfate content. 

Table 7.Rank distribution analysis of potential versus cadmium sulfate content in a standard cell at 25 °C [20]. The bracketed numbers are observed values EMI =...

Descriptions of analytical methods for strong acid and acidic sulfate content of atmospheric aerosols have been reviewed (6-10). Methods for acidic aerosol determination are reviewed in this chapter according to the measurement principle either filter collection and post-collection extraction, deriv-atization or thermal treatment, and analysis or in situ collection (real-time or stepwise) and analysis. 

Due to the burning of cotton plant wastes (hulls, leaves, etc.), the sulfate content in the air over a town is highest during the month of November. If the data given below are the mean values of sulfate content during the month of November (analysis of air perform daily) over the past 10 years. 

I was characterized by powder X-ray diffraction (PXRD), energy dispersive analysis of X-rays (EDAX), chemical analysis, thermogravimetric analysis (TGA) and IR spectroscopy. EDAX analysis indicated the ratio of Mn S to be 3 2. The presence of fluorine was confirmed by analysis and the percentage of fluorine estimated by EDAX in a field emission scanning electron microscope was also satisfactory. Thermogravimetric analysis also confirms the stoichiometry of the compound. Bond valence sum calculations6 and the absence of electron density near fluorine in the difference Fourier map also provide evidence for the presence of fluorine. The sulfate content was found to be 30.8% compared to the expected 32% on the basis of the formula. 

Comparison with Horemheb s Tomb. The results were compared with those obtained from the analysis of the plaster of the royal tomb of Horemheb (number 57, Valley of the Kings, Thebes, Upper Egypt) (Figure 4). The tomb of Horemheb, approximately 80 years older than that of Nefertari, has been recently restored and is now relatively well preserved (36). It was excavated from limestone of excellent quality, and its original plaster is strong and cohesive. A comparison of the chloride and sulfate contents of... 

Attempts to increase pyrite removal by increasing the reaction time met with limited success under our standard conditions because reaction of the ferric ion with the coal matrix depleted the ferric ion that was needed for extraction of the pyrite. Thus, for example, increasing the coal reaction time from 2 to 12 hrs only increased pyritic sulfur removal from 60 to 80% for Pittsburgh coal. Similar results were obtained for the other three coals. The only alternatives were to increase the amount of leach solution or to use a continuous or semi-continuous (multiple-batch) reactor. A multiple-batch mode was chosen because it was a simple laboratory procedure and at the same time it could approximate conditions encountered in a commercial plant. A 1-hr-per-batch leach time was used because our 2 hr results indicated that in the early stages of removal the rate begins to decrease after 1 hr, and six leaches (or batches) per run were used to assure that any pyrite that could be removed in a reasonable amount of time was removed. The progress of removal was monitored by analyzing the sulfate content in each spent leach solution elemental sulfur was not removed until all the leaches were completed. Table VII shows pyrite extraction as a function of successive leaches as followed by sulfate analysis of the leach solution. Note that the major portion of pyritic sulfur is removed in the first two leaches or 2 hrs, followed by lesser amounts in... 

Characterization results of Table 1 show that the sulfate retained on the mixed oxide is proportional to the nominal sulfate content, with nearly total sulfate retention for nominal sulfate loadings up to 5 wt%. The S/Zr atomic surface ratio (determined by XPS), the surface area, and the surface coverage regularly increase with the amount sulfate determined by chemical analysis. 

The conversion - time curves (not shown here) of the different catalysts show a loss of conversion (deactivation) in the first hours of the reaction. This loss is insignificant for the catalyst with the smallest sulfate content which is nearly inactive, but it increases with the sulfate content as shown in Fig. 6 where the initial and steady conversions are plotted as a function of the sulfate content determined by chemical analysis. Up to 6.4 wt% (7.5 nominal %), the conversion linearly increases with the sulfate content, and decreases at higher contents. The increase of conversion is accompanied by a small... 

Analysis. The contents of a weighed ampoule are placed in an Erlenmeyer flask containing 50-70 ml. of ice-cold 2N H3SO4. The decomposed product is boiled for one half hour and the graphite is filtered off and washed. The alkali is determined as sulfate in an aliquot of the filtrate KOH is added to another aliquot, and the NH3 is distilled off and determined by volumetric analysis. The dried graphite is treated as described for potassium graphite compounds. 

PURPOSE OP EXPERIMENT Prepare KA1(S04)2 12H20, an aluminum alum, from aluminum metal. (Note Experiment 14 describes the gravimetric analysis of the sulfate content in alum.)... 

Chen, Conjeaud, and Lehoux (1985) estimated burn ing zone temperatures with three techniques by burnability studies of the raw mix, by electron micro probe analysis of alite in clinker, and by birefringence of alite. The latter method was said to be the least accurate, due possibly to clinker magnesium oxide and sulfate contents, kinetics of alite crystallization from a melt, raw mix particle size, and variable calcination rates. 

J. Use of Low-Sulfate Salts. ITiere is great variation in the concentrations of impurities, including sulfate, in natural salts. This should be an important part of the value analysis when choosing a raw material. Several grades of salt are purified by processing (Section 7.1.5), and some of these have attractively low sulfate contents. We discuss several forms of processed salt below. 

Native polysaccharides with acid groups other than the uronic type are not very common except for the sulfate esters. Total acidity may be estimated by direct titration, but erroneous results are obtained if the polysaccharide is alkali-labile as is the case with many oxidized polysaccharides. Addition of calcium acetate (7, 8) or sodium bromide 8, 9) to the polysaccharide solution increases the accuracy of the titration. Other methods for the estimation of carboxyl and other acidic groups involve determination of the amount of methylene blue absorbed, or determination of the amount of silver salt formed by exchange from a solution which contains silver in combination with a very weak acid. The sulfate content of polysaccharide sulfates, such as agar, is obtained by ordinary sulfate analysis of the completely hydrolyzed or ashed polysaccharide. 

Analysis No. 6 characterizes water from a deep well in the Middle East with high coexisting chloride and sulfate content. It is brackish water whose TDS is in excess of 100° (or 1000 ppm as CaC03). 

Abimbola, O., Cox, D.S., Liang, Z., and Eddington, N.D., Analysis of glucosamine and chondroitin sulfate content in marketed products and the Caco-2 permeability of chondroitin sulfate raw materials. J. Am. Nutraceut. Assoc., 3, 37, 2000. 

VoOGT and van Rheenen 645) isolated asterosaponins from the gonads, the pyloric caeca, the stomach and the body wall of female specimens of Asterias rubens and determined the sugar and sulfate content for each saponin. On the basis of a statistical analysis which showed that the sugar content in the substances of the pyloric cecum was significantly lower than those in the other parts, they hypothesized that the saponins are formed in the pyloric cecum, and that they are modified slightly in each tissue, in particular by addition of fucose units. The authors found that the haemolytic activity increased with the molar ratio of carbohydrate to sulfate. 

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