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Table 2 Postulated chemical reaction and the Gibbs energy for the studied compounds. O2 (∆Gf = 0 kJ mol−1) not shown

From: Critical evaluation of the microbial turnover to biomass approach for the estimation of biogenic non-extractable residues (NER)

Compound Gf0 kJ/mol Reaction
2,4-D − 443.5 C8H6O3Cl2 + 7.5 O2 → 8 CO2 (g) + 2H2O (l) + 2HCl
Ibuprofen − 184.0 C13H18O2 + O2 → 13 CO2 + 9 H2O
Glyphosate − 1480 C3H8NO5P → 3 CO2
Glyphosate → AMPA − 268 C3H8NO5P → CH6NO3P + 2 CO2
Bisphenol S − 145.4 C12H10O4S → 12 CO2 + 5H2O + (S ignored)
Dodecylphenol 1200 C18H30O → 18 CO2 + 15 H2O
DS, DA   same yield taken as for dodecylphenol
Bromoxynil 147.8 C7H3Br2NO + 6 O2 + OH  → 7 CO2 + 2 Br  + NH4+
Isoproturon 64.2 C12H18N2O → 12 CO2 + 7.5 H2O + 2 NH3
MCPA − 443.8 C9H9ClO3 → 9 CO2 + 4 H2O + HCl
Metamitron 414.8 C10H10N4O → 10 CO2 + 3 NH3 (NH3 disregarded)
Pendimethalin 944.3 C13H19N3O4 → 13 CO2 + 8 H2O (+ NH3 + 2NO2 disregarded)
Sulfadiazine 270.3 C10H10N4O2S + 2H2O → 10 CO2 + 4 NH3 + H2SO4
  1. Assumptions: N and S keep the oxidation state they have in the parent molecule. In the ∆Gr of pendimethalin and metamitron, formation of NH3 and NO3 was disregarded in the calculation of ∆G0r. Furthermore, it was assumed that in the unit gC/gC, DA is dodecylbenzyl trimethylammoniumchloride (DA) and dodecylbenzene sulfonic acid (DS) have the same yield as dodecylphenol, because the functional group is removed in the degradation chain. Glyphosate has two degradation pathways, one leading to complete mineralization, and one where AMPA is formed [16]