In the current study, the heterogeneous reaction of NO2 with soot/bio-soot surfaces was investigated in the dark and under illumination relevant to the atmosphere conditions (JNO2 = 0.012 s-1). A flat-flame burner was used for preparation and collection of soot samples from premixed flames of liquid fuels. The biofuels were prepared by mixing 20% v/v of (i) 1-butanol (CH3(CH2)3OH), (ii) methyl octanoate (CH3(CH2)6COOCH3) (iii) anhydrous diethyl carbonate (C2H5O)2CO and 2,5 dimethyl furan (CH3)2C4H2O additive compounds in conventional kerosene fuel (JetA-1). Experiments were performed at 293 K using a low-pressure flow-tube reactor (P = 9 Torr) coupled to a quadrupole mass spectrometer. The initial and steady-state uptake coefficients, γ0 and γss respectively, as well as the surface coverage, Ns, were measured under dry and humid conditions. Furthermore the branching ratios of the gas phase products NO (~80-100%) and HONO (<20%) were determinedSoot from JetA-1/2,5-dimethyl furan was the most reactive γ0 = (29.1±5.82)×10-6, γss¬(dry) = (9.09±1.82) ×10-7 and γss¬(5.5%RH) = (14.0±2.80) -7 while soot from JetA-1/1-butanol [γ0 = (2.72±0.544)×10-6, γss¬(dry) = (4.57±0.914) ×10-7, γss¬(5.5%RH) = (3.64±0.728) -7] and JetA-1/diethyl carbonate [γ0 = (2.99±0.598)×10-6, γss¬(dry) = (3.99±0.798) ×10-7, γss-(5.5%RH) = (4.80±0.960)-7] were the less reactive. To correlate the chemical reactivity with the physicochemical properties of the soot samples, their chemical composition was analysed employing Raman spectroscopy, NMR, and HPLC. In addition, the BET adsorption isotherms and the particles size distributions were determined employing a Quantachrome Nova 2200e gas sorption analyser. The analysis of the results showed that factors such as (i) soot mass collection rate, (ii) porosity of the particles formed, (iii) aromatic fraction and (iv) pre-existence of nitro-containing species in soot samples (formed during the combustion process) can be used as indicators of soot reactivity with NO2.