Water is the lifeblood of everything on earth, nourishing
and nurturing
all forms of life, while also contributing to the development of civilization.
However, with the rapid development of economic construction, especially
the accelerated process of modern industrialization, the pollution
of oily sewage is becoming increasingly serious, affecting the ecological
balance and human health. The efficient elimination of pollutants
in sewage is, therefore, particularly urgent. In this paper, a core–shell
microbial reactor (MPFA@CNF-SA-AM) was fabricated by using nanocellulose
and sodium alginate (SA) particles embedded with microorganisms as
the core and lipophilic and hydrophobic fly ash as the outer shell
layer. Compared with that of free microorganisms and cellulose and
SA aerogel pellets loading with microorganisms (CNF-SA-AM), which
has a degradation efficiency of 60.69 and 82.89%, respectively, the
MPFA@CNF-SA-AM possesses a highest degradation efficiency of 90.60%
within 240 h. So that this self-floating microbial reactor has selective
adsorption properties to achieve oil–water separation in oily
wastewater and high effective degradation of organic pollutants with
low cost. The adsorption curves of MPFA@CNF-SA-AM for diesel and n-hexadecane were studied. The results showed that the adsorption
follows the Freundlich model and is a multimolecular layer of physical
adsorption. In addition, the degradation mechanism of diesel oil was
studied by gas chromatography–mass spectrometry. The results
showed that diesel oil was selectively adsorbed to the interior of
MPFA@CNF-SA-AM, and it was degraded by enzymes in microorganisms into n-hexadecanol, n-hexadecaldehyde, and n-hexadecanoic acid in turn, and finally converted to water
and carbon dioxide. Compared with existing oily wastewater treatment
methods, this green and pollution-free dual-functional core–shell
microbial reactor has the characteristics of easy preparation, high
efficiency, flexibility, and large-scale degradation. It provides
a new, effective green choice for oily wastewater purification and
on-site oil spill accidents.