Decomposition of long-chain petroleum hydrocarbons by Fenton‐like processes : effects of ferrous iron source, salinity and temperature

Batch experiments were conducted to examine the effects of ferrous iron source, soil salinity and temperature ondegradation of long-chain petroleum hydrocarbons by Fenton-like processes. The results show that over 70%,50% and 25% of aliphatic C16-C21, C21-C35 and C35-C40, respectively, was eliminated at a H2O2 dose of 1.5%.The decomposition rate of petroleum hydrocarbons was similar to each other for ferrous sulfate and magnetitewhile the capacity of pyrite to trigger Fenton-driven decomposition of long-chain aliphatic petroleum hydrocarbonswas weaker, as compared to ferrous sulfate and magnetite. The decomposition rate of aromatic hydrocarbonsdecreased with increasing length of carbon chain in the ferrous sulfate and magnetite systems, butthe opposite was observed in the pyrite system. The effect of Fenton-like process on degradation of long-chainpetroleum hydrocarbons was enhanced by increased temperature. At a temperature of 60 °C, the enhancement ofFenton process outweighed the adverse effects from potential loss of H2O2 due to elevated temperature. The useof magnetite as a source of ferrous iron was likely to prevent consumption of Fe2+ by complexation with chlorideion from occurring and consequently effectively eliminated the inhibitory effect of salinity on Fenton reaction