[Model fitting results of pyrene sorption on soil after gradient oxidations by different oxidants]

The influences of the sorption of pyrene on soils after the gradient oxidations with Fenton and NaClO on soil were investigated using two different soil samples from Dongling, Beijing (DL) and Qujing, Yunnan (YN), China. Six models were used to simulate the sorption using coefficient of determination (R2) and mean weighted square errors (MWSE) to evaluate the goodness of fitting. The results showed that Polanyl-Manes model fitted best among all these models. Both gradient oxidations secured the positive correlation between adsorption capacity of DL soil and TOC, while the results for YN soil were on the opposite. The adsorption capacities of YN soils oxidated by NaClO were stronger than that oxidated by Fenton while opposite results were identified for DL soils. YN soils oxidated by NaCIO had stronger adsorption capacities than DL soils. The adsorption of pyrene was influenced by TOC of soil with high TOC ( < 2.5%) while no influences were identified with low TOC (0.1%-0.5%). Both DL and YN soils oxidated by NaC1O had more equilibrium adsorption potentials. The equilibrium adsorption potentials had good significant linear relationships with TOC. DL soils oxidated by NaClO secured the positive correlation between equilibrium adsorption potentials and TOC, while opposite results were identified in other three oxidated soil groups.