Distillate analysis

An extremely violent detonation occurred when 2-butanol, which had been stored for ten years, was distilled. Analysis that was carried out after the accident on what was left from butanol showed that it contained 12% of peroxides. An exactly similar accident was mentioned with 2-butanol distilled after being stored for twelve years. The analyses carried out after the accident led to the same level of peroxides. It seems that traces of butanol must have played a role of promoter In the peroxidation. 

Simulated distillation analysis was carried out on the extract and filtrate produced after precipitation, focusing on the fractions which boiled below 350°C. A Perkin Elmer model 8500 GC fitted with a wide-bore, OV-1 capillary colunm, 25 m long and 0.53 pm in diameter, was used. The oven temperature was held at 40 C for 1 minute and then increased at a rate of 4 C per minute to 250 C, where the temperature was held. There was no split on the injection and a FID detector was used. Initial fractionation of the samples was carried out by vacuum distillation. 

The ketones used were in most cases obtained from commercial sources and purified by distillation. Analysis by gas chromatography showed a purity greater than 98% in all cases. Dialkyl ketones not available commercially were synthesized from the appropriate acids using an iron catalyst and the method of Davis and Schultz (3). 

Rouelle s thoughts on chemical analysis reflected his expertise in the distillation analysis of vegetables. He accepted Stahl s premise that chemistry had long been occupied with the decomposition of supercompounds into compounds without penetrating more deeply into the composition of compounds or mixts. Such analysis would require well-proportioned instruments and a well-adjusted movement. Rouelle did not believe that solution methods could provide proper means for this kind of... 

Reagents. The butenes (Matheson, CP grade) were purified further before use by repeated low-temperature distillation. Analysis by GLC showed that the individual butenes then contained only negligible amounts of lower molecular weight compounds. Deuterium (Matheson) was purified by diffusion through a palladium thimble. The deuterium oxide (99.7%) was obtained from I.C.I. Ltd. and was degassed before use. 

J.-U. Repke, F. Fomer, A Klein, 2006, Separation of Homogeneous Azeotropic Mixtures by Pressure Swing Distillation - Analysis of the Operation Performanee, Chem. Eng. Techn., vol. 28, 1151-1557. 

Such solvents might be paint thinners, called Varnish Makers and Painters (V.M. P.) naphthas or mineral spirits. There are many other specialty solvent fractions manufactured in petroleum refineries. The product specifications for these solvents as well as for many refinery products are often given in terms of the simple ASTM distillation boiling ranges. However, for best results in modeling, precision distillation analysis is used, with end-product correlation to compare with specifications. Such an approach is often used also for fuel fractions, even to the extent of controlling the operation with gas chromatographic precision distillation analysis. 

A complete distillation analysis of unstabilized California natural gasoline has been published by Boultbee (6). 

Distillation analysis is based on the fractionation of the sample by boiling temperature. This type of analysis can be carried out only up to a maximum temperature of approximately 350°C, since at higher temperatures cracking of the heavy organic components occurs. 

Distillation analysis gave the distribution of products shown in Figure 4. 

The second system is data published by Roland, Smith, and Kaveler (117) for a gas condensate system. The heptanes plus fraction is divided using a distillation analysis reported by those authors. The comparisons between the predicted and experimental K values at three temperatures are shown in Figures 21b and 22. The agreement between the predicted and experimental K values is good except for the heptanes plus K value at 120° and 200°F. 

Robillard MV, Spock PS, and Whitford JH (1991) An Overview of Methodology and Column Technology for Simulated Distillation Analysis. Bellefonte, PA Supelco. 

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