Estimation of the molecular mass range of the tar from pyrolysis of casein by gas chromatography-mass spectrometry, probe mass spectrometry and size exclusion chromatography with 1-methyl-2-pyrrolidinone as eluent.
Casein has been pyrolysed to obtain a biochar (28.3% yield), with mostly meso- and macro-pore structure, and a liquid tar product of high yield (37.5%) with the balance as gas (20.9%) and water (13.3%). The elemental composition of the casein tar was: C 66.7%, H 8.3%, N 12.1% and O 12.9% (by difference). The tar sample has been characterised by mass spectrometry, gas chromatography (GC)/MS and heated-probe MS, to give molecular mass distributions for comparison with molecular mass ranges indicated by analytical-scale size-exclusion chromatography (SEC). The tar appeared to be completely soluble in 1-methyl-2-pyrrolidinone (NMP), the solvent used for SEC. It appeared to consist mostly of lower molecular mass fractions with elution times at 18-26 min. GC/MS analysis showed the presence of both aliphatic and aromatic nitrogen-containing components. Neither GC/MS nor heated-probe MS were able to detect more than about half the tar components.
Purevsuren
B
B
Institute of Chemistry and Chemical Technology, Mongolian Academy of Sciences, Ulaanbaatar,51, Mongolia.
Avid
B
B
Davaajav
Ya
Y
Herod
A A
AA
Kandiyoti
R
R
Morgan
T J
TJ
D000818:Animals; D002364:Caseins / Q000737:chemistry*; D002417:Cattle; D002850:Chromatography, Gel / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006358:Hot Temperature; D008970:Molecular Weight; D011760:Pyrrolidinones / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013638:Tars / Q000737:chemistry*
D002364:Caseins; D011760:Pyrrolidinones; D013638:Tars; C038678:N-methylpyrrolidone