Residue ignition loss

This dilemma can be resolved partly by treating the minerals with hydrochloric acid. Carbonates dissolve, whereas silica and combustible matter do not. But the presence of bitumen and even vegetal matter interferes more or less with the reaction with hydrochloric acid, so the cleanest way to carry out acid treatment is on ignition residues. The ratio of acid solubles to ignition loss will then be below 56 44 in proportion to the amount of combustibles present. But because some common minerals dissolve in hydrochloric acid whereas other do not, the conventional method of mineral analysis is approximate at best. 

Figure 2. Variation of ignition loss of residue and decomposition ratio of com bustibles with loading rate of dried cake...

The basis for rate cements to individual kinds is cement composition based principally on chemical determinations, to which belong insoluble residue and loss on ignition. They are principally linked with cement additions. For quantitative slag content determination from long time the light microscopy is used, and the accuracy of this method is assessed to be 5 % (Fig. 1.6). Lastly also the methods of separation in heavy liquids are recommended, based on the density differences of individual cement components clinker about 3.1 g/cm, slag 2.85 g/... 

ASTM D6844 Purity by HPLC Method ASTM D6740 Ignition Loss Test for Residue... 

For routine purposes the salicylic acid may be determined directly by bromination as above, and the boric acid by a short ignition to remove salicylic acid and titration of the residue the loss of boric acid by volatilisation is negligible if the ignition is not protracted. 

Applications Quantitative dry ashing (typically at 800 °C to 1200°C for at least 8h), followed by acid dissolution and subsequent measurement of metals in an aqueous solution, is often a difficult task, as such treatment frequently results in loss of analyte (e.g. in the cases of Cd, Zn and P because of their volatility). Nagourney and Madan [20] have compared the ashing/acid dissolution and direct organic solubilisation procedures for stabiliser analysis for the determination of phosphorous in tri-(2,4-di-t-butylphenyl)phosphite. Dry ashing is of limited value for polymer analysis. Crompton [21] has reported the analysis of Li, Na, V and Cu in polyolefins. Similarly, for the determination of A1 and V catalyst residues in polyalkenes and polyalkene copolymers, the sample was ignited and the ash dissolved in acids V5+ was determined photo-absorptiometrically and Al3+ by complexometric titration [22]. 

POLYURETHANE FOAM SHEETS OR BLOCKS. These are required to resist ignition source 5 (17 gram wood crib) of BS5852 Part 2 except that the flames may penetrate the full depth of the specimen and that the mass loss (due to burning and liquid residues falling from the test rig) shall not exceed 60 grams. 

Part—I has three chapters that exclusively deal with General Aspects of pharmaceutical analysis. Chapter 1 focuses on the pharmaceutical chemicals and their respective purity and management. Critical information with regard to description of the finished product, sampling procedures, bioavailability, identification tests, physical constants and miscellaneous characteristics, such as ash values, loss on drying, clarity and color of solution, specific tests, limit tests of metallic and non-metallic impurities, limits of moisture content, volatile and non-volatile matter and lastly residue on ignition have also been dealt with. Each section provides adequate procedural details supported by ample typical examples from the Official Compendia. Chapter 2 embraces the theory and technique of quantitative analysis with specific emphasis on volumetric analysis, volumetric apparatus, their specifications, standardization and utility. It also includes biomedical analytical chemistry, colorimetric assays, theory and assay of biochemicals, such as urea, bilirubin, cholesterol and enzymatic assays, such as alkaline phosphatase, lactate dehydrogenase, salient features of radioimmunoassay and automated methods of chemical analysis. Chapter 3 provides special emphasis on errors in pharmaceutical analysis and their statistical validation. The first aspect is related to errors in pharmaceutical analysis and embodies classification of errors, accuracy, precision and makes... 

Cool the crucible in a desiccator and weigh. Add to the ignited residue 5 ml coned hydrofluoric acid one drop coned sulfuric acid. Evaporate the acid, ignite the residue, cool in a desiccator and weigh. The difference in wt before and after adding HF is due to the loss of silica... 

Determination of Silica (Applicable to Grade ll IV onlyJ. To the ash in the platinum crucible, add 5 ml of HC1 and a few drops of sulfuric acid. Evaporate and ignite. Cool in a desiccator and weigh. Calculate the loss in weight as percent silica as follows, and retain the residue for grit detn ... 

Loss on drying Residue on ignition Organic volatile impurities... 

Sulfur is determined as the further loss of weight on extraction with carbon disulfide in a Wilcv extractor or other suitable apparatus. After the extraction, the crucible ought to be allowed to dry in the air away from flames until all the inflammable carbon disulfide has escaped. It is then dried in the oven to constancy of weight, and the residue is taken as charcoal. Ash is determined by igniting the residue in the crucible until all carbon has burned away. A high result for ash may indicate that the water extraction during the determination of potassium nitrate was not complete. The analytical results may be calculated on a moisture-free basis for a closer approximation to the formula by which the manufacturer prepared the powder. 

The standard test method for proximate analysis (ASTM D-3172) covers the methods of analysis associated with the proximate analysis of coal and coke and is, in fact, a combination of the determination of each of three of the properties and calculation of a fourth. Moisture, volatile matter, and ash are all determined by subjecting the coal to prescribed temperature levels for prescribed time intervals. The losses of weight are, by stipulation, due to loss of moisture and, at the higher temperature, loss of volatile matter. The residue remaining after ignition at the final temperature is called ash. Fixed carbon is the difference of these three values summed and subtracted from 100. In low-volatile materials such as coke and anthracite coal, the fixed-carbon value equates approximately to the elemental carbon content of the sample. 

Evaluation of assays (loss on drying, bulk density, particle size, and residue on ignition as deemed appropriate for trends, shifts, and out-liners). 

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