Paraffins- olefins - naphthenes - aromatics PONA analysis

For some liquid feedstocks such as naphthas, the componential composition is often obtained by gas chromatography (GC) and/or mass spectrometry (MS). For gas oils or heavier feedstocks, it is impossible to obtain the desired analysis. Paraffins, olefins, naphthenes, aromatics (PONA) grouping is sometimes used as a means of feed characterization. For gas oils. Bureau of Mines Correlation Index (BMCI) has been used as a parameter for feed characterization. Since the 1980s, nuclear magnetic resonance (NMR) spectroscopy has been used to characterize heavy feedstocks. 

Cooperative studies are underway in ASTM D02.04 to find a better test method for total olefins. Cooperative work has been done to validate new gas chromatographic methods that trap the olefins on silver nitrate impregnated traps. These include a gas chromatographic multi-dimensional procedure for oxygenates and paraffin, olefin, naphthene, aromatic (O-PONA) hydrocarbon types in petroleum distillates and a GC fast total olefins analyzer (FTO) method. The FTO method has the advantage that the analysis time is quicker. The O-PONA method is an expanded version of ASTM D5443 and... 

When simple Hquids like naphtha are cracked, it may be possible to determine the feed components by gas chromatography combined with mass spectrometry (gc/ms) (30). However, when gas oil is cracked, complete analysis of the feed may not be possible. Therefore, some simple definitions are used to characterize the feed. When available, paraffins, olefins, naphthenes, and aromatics (PONA) content serves as a key property. When PONA is not available, the Bureau of Mines Correlation Index (BMCI) is used. Other properties like specific gravity, ASTM distillation, viscosity, refractive index. Conradson Carbon, and Bromine Number are also used to characterize the feed. In recent years even nuclear magnetic resonance spectroscopy has been... 

In summary, the terminology used for the identification of the various methods might differ. However, in general terms, group-type analysis of petroleum is often identified by the acronyms for the names PONA (paraffins, olefins, naphthenes, and aromatics), FIONA (paraffins, isoparaffins, olefins, naphthenes, and aromatics), PNA (paraffins, naphthenes, and aromatics), PINA (paraffins. 

Compositional information from gas chromatographic analysis is more definitive than distillation data. A naphtha composition is given in Table 1. The composition is given after the naphtha has been hydrotreated to lower concentrations of olefins and contaminants. Some of the paraffin isomers are lumped together in this particular analysis. The compositional information is often categorized into the classes of paraffins, olefins, naphthenes, and aromatics, and is called a PONA. The ease of reforming feedstocks has been correlated to the sum... 

PONA analysis a method of analysis for paraffins (P), olefins (O), naphthenes (N), and aromatics (A). 

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