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Efficient elimination of organic pollutants from wastewater is of great importance for sustainable human development. In this work, we report the fabrication of oleophilic porous activated sludge loading with microorganism (OPAS-M), which was prepared through multi-step doping of the microorganism into the as-prepared porous network of activated sludge (AS) followed by a hydrophobic surface modification, so that it has selective adsorption properties to achieve oil-water separation in oily wastewater and high effective degradation organic pollutions. Thanks to its abundantly porous structure and oleophilic wettability, the petroleum pollutants in wastewater (using n-hexadecane as model compound) can be selectively absorbed inside the OPAS-M and then could be biodegraded by the loaded microorganism. Compared with that of free microbial and porous activated sludge loading with microorganism (PSA-M) which has a degradation efficiency of 58.80% and 74.37%, respectively, the OPAS-M possesses a higher removal efficiency of 84.7%. The degradation kinetics of free microorganism, PAS-M and OPAS-M all fit well with the first-order kinetic equation, their degradation half-life is measured to be 7.44 d, 3.56 d, and 2.23 d, respectively. In addition, OPAS-M has good stability and tolerance, and the degradation efficiency can reach more than 50% in a poor environment. The degradation mechanism of n-hexadecane was studied by GC-MS. The results showed that n-hexadecane was selectively adsorbed to the interior of OPAS-M, and it was be degraded by enzymes in microorganism into n-hexadecanol、n-hexadecaldehyde and n-hexadecanoic acid in turn, and finally converted to water and carbon dioxide. The combination of selective absorption and biodegradable OPAS-M may open up a green and efficient way in the biological remediation of organic pollutants. [Display omitted] • Oleophilic porous activated sludge loading with microorganisms (OPAS-M) was prepared. • OPAS-M has selective adsorption ability of organic pollutants from waste water. • OPAS-M can rapidly degrade the model organic pollution with high efficiency. • Harmful organic pollution can be spontaneously converted into H 2 O and CO 2 by OPAS-M. • OPAS-M has better tolerance in various environments. [ABSTRACT FROM AUTHOR]

The effect of natural attenuation, biostimulation and bioaugmentation-biostimulation on the removal of petroleum pollutants, specifically Total Petroleum Hydrocarbons (TPH), as well as Polycyclic Aromatic Hydrocarbons (PAHs) in a refinery solid waste was estimated. The experimental procedure took place on a laboratory scale in three separate tanks (natural attenuation, biostimulation and biostimulation-bioaugmentation tank) for a period of 80 days. Optimal conditions of temperature, humidity and ventilation were applied in order to ensure an efficient performance of the microdigesters. According to the results, addition of indigenous microorganisms and nutrients in biostimulation-bioaugmentation tank, proved to be particularly effective on the biodegradation of petroleum pollutants, achieving a removal efficiency of 52 and 87% for TPH and PAHs, respectively. In the biostimulation tank, the efficiency of TPH and PAHs removal was 47 and 59%, accordingly. Less effective appeared to be the natural attenuation process with a reduction efficiency of 37% for TPH and 42% for PAHs. [ABSTRACT FROM AUTHOR]