Catalysis 2023 Issue

1.4

Biogenic carbon, 2%

Biogenic carbon

Fossil carbon

1.2

Co-processing run, k ero product

Fossil run, k ero product

0.8

0.6

Fossil carbon, 98%

0.4

no carbon-14 isotope). In this application, the amount of biogenic carbon in the product fractions can be directly correlated to the relative amount of product resulting from vegetable oil during co-processing. Results from the biogenic carbon analyses in the prod- uct fractions are discussed in conjunction with the product chromatograms in Figures 6, 8 and 10 . Kerosene product Interpreting a simulated distillation curve as a probability plot is shown in Figure 6, where the temperature on the x-axis refers to the average boiling point of lumps of mate- rial boiling in 1°C intervals, making identification of differ - ent quantities of specific components possible. We can, for example, infer from this chromatogram that there was a higher concentration of nC15 (BP 271°C) in the kerosene product during the co-processing test run compared to the fossil run. The presence of carbon sourced from vegetable oil during co-processing is further validated by biogenic carbon analyses showing a 2% carbon-14 isotope (see Figure 7 ). Diesel product Two of the most well-defined peaks can be seen in the diesel chromatogram in Figure 8, corresponding to nC16 (BP 287°C) and nC18 (BP 317°C). The other two smaller Figure 7 Result from ASTM D6866 test for distinguishing carbon isotopes in kerosene sample drawn during the test run

0.2

100

150

200

250

300

Temp, ˚C

Kero product - 100% fossil run

Kero product - 5% co-processing run

Figure 6 Chromatogram of kerosene product sample drawn during the test run

Chain length

Boiling point, °C

nC14 nC15 nC16 nC17 iC18 nC18 nC19

254 271 287 303 303 317 330

Product samples were also analysed for biogenic carbon content by ASTM D6866. This is done by distinguishing carbon isotopes from biogenic sources (containing well- characterised amounts of carbon-14 isotope) against car- bon from fossil sources (containing carbon-12 isotope and

1.8

1.6

1.4

1.2

Biogenic carbon, 9%

Biogenic carbon

Fossil carbon

0.8

0.6

0.4

Co-processing run, d iesel product

Fossil run, d iesel product

0.2

100

200

300

400

Temp, ˚C

Fossil carbon, 91%

Diesel product - 100% fossil run

Diesel product - 5% co-processing run

Figure 8 Chromatogram of diesel product sample drawn during the test run

Figure 9 Result from ASTM D6866 for distinguishing carbon isotopes in diesel sample drawn during the test run

Catalysis 2023