Fossil origin

The chemical and enzymatic oxidative degradation of lignin (and coal) is used to obtain not only vanillin and benzoic acid, but also other aromatics (Baciocchi et al. 1999, references therein). In principle, lignin could be a major nonfossil and renewable source of aromatic compounds, a feedstock for synthesis of useful products. The problem deserves finding new ion-radical routes to cleave lignin. At present, there is some shortage in oil, gas, and even coal, which had usually been well-available natural sources of aromatics. In the near future, biomass may (and must) replace fossil-originated materials in the manufacture of commercial carbon-based products. 

We have seen in this work that most of the regional Pleistocene sediments have yielded mammalian fossils originating from the Upper Pleistocene, i.e. the no. II terrace surfaces and the Upper Pleistocene loess. In addition, the upper layers (down to ca. 40-50 m) of the filling material of the Great Hungarian Plain—just like the swamp loess of the Tisza, or its bluish clay —have been found to contain fossils dated to the Lower Wiirm (Janossy and Voros, 1979). 

Free of sulphur and aromatics in contrast to conventional fuels from fossil origin. 

PASH, sulfides, thioles Matter of fossil origin as coal, mineral oil or derived products, released during combustion Air, water, soil... 

Ape man fossils Origin of grass Rise of cats, dogs, pigs Debut of hoofed mammals Earliest primates... 

Provenance The area or geological unit from which a sediment or fossil originates. 

Table 18.6 Typical properties of different bio- and fossil-origin diesel product streams...

Polymers from fossil origin Polymers from renewable 100 5,000 23,000 33,000 75,000... 

Despite the fact that this method is very simple in principle, several studies have highlighted various practical challenges and factors that must be considered (Van Stiydonck et al., 1986). These arise mainly from the contamination of samples with carbonaceous substances such as incompletely burnt limestone and aggregates of fossil origin including limestone sand. 

---