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Valorization of food waste into high value-added glycerol was designed and prepared via directional green transformation using multi-enzymolysis saccharification coupled facultative fermentation by Saccharomyces cerevisiae. The optimal conditions for the first step of multienzyme hydrolysis and the second step of facultative fermentation were 55 °C and pH 5.0 for 6 h, 30 °C and pH 7.0 for 70 h, respectively. The glycerol yield efficiency and kinetic rate constant were 73.6 % (w / w) and 0.681 h−1 for dry component of food waste, while the other 27.4 % was utilized as the growth energy substrate. The key points of transformation were the synergistic directed enzymolysis to produce 3 % glycerol and 95 % reducing sugars. Furthermore, the reducing sugars were converted into glycerol by switch the metabolic pathway from ethanol into glycerol through the quantitative expression of functional gpd1 and gpp2 genes activated GPD and GPP enzymatic activity and synchronous inhibition of adh gene for glycerol production with Na 2 SO 3 regulation. The economic income was 135.52 USD/ton for converting 80 % water content of kitchen waste into glycerol. This finding provided an economic value-added approach to produce high-value glycerol for cost-effective recycling of food waste using commercial yeast. [Display omitted] • Glycerol produced from food waste through two-step green directional conversion. • Food waste hydrolysate into 95 % reducing sugar and 3 % glycerol. • Glycerol yield was 73.6 % through reducing sugar microaerobic fermentation. • Glycerol production was controlled by functional enzyme genes gpd1 and gpp2. • Economic income was 135.52 USD/ton for kitchen waste conversion to glycerol. [ABSTRACT FROM AUTHOR]

2,4,6-Trichlorophenol (2,4,6-TCP) is commonly used in the production of insecticides and preservatives with the characteristics of accumulation and toxicity due to the complex chemical structure with a halogenated aromatic ring. In order to effectively degrade and mineralize 2,4,6-TCP from water, a stack-coral-like catalyst of magnetic sulfur doping constructed nitrogen vacancies in graphitic carbon nitrides (Fe 3 O 4 /S-g-C 3 N 4 , FSCN-T) was designed and prepared through polymerization combined with precipitation. This visible-light-driven photocatalytic degradation to 5 mg/L 2,4,6-TCP was 95 % within 60 min with 0.1 g/L FSCN-T amendment. The degradation and carbonization rate constant were 0.118 and 0.089 min−1 respectively. This high removal was attributed to nitrogen vacancies, which broaden the visible light absorption range and shorten the electron transfer path with narrow CN bandgap (from 2.94 eV to 2.49 eV). Moreover, the introduction of iron accelerated electron cycling and enhanced magnetic recovery performance with above 95 % recovery and catalytic stability after 5 cycles of use. The degradation contribution from the active species were h+ (41 %)> •OH (28.9 %) > •O 2 -(16.1 %)>1O 2 (8.7 %). This degradation underwent three pathways of substitution, elimination, and hydroxyl oxidation. Further, the intermediates were oxidized with ring opening and mineralization according to density functional theory (DFT) calculations and LC-Qtof-MS identification. The oxidative degradation process reduced the toxicity of 2,4,6-TCP and its intermediates. This study provided an efficient catalyst and low-energy consumption approach for toxic wastewater treatment. [Display omitted] • The sulfur doped defect state graphite nitride carbon coupled Fe 3 O 4 was prepared. • Removal efficiency and mineralization of 2,4,6-TCP were 95 % and 72.1 % in 60 min. • The spectral broadening and band gap reduction of CN after modification. • FSCN-T shortened the path and improved the efficiency of electron transfer. • Catalytic recovery and 2,4,6-TCP removal efficiency kept above 95 % after five recycles. [ABSTRACT FROM AUTHOR]

Dimethyl phthalate (DMP) is widely used as plasticizer, and this kind of plastic industry wastewater is refractory due to the complex chemical structure and endocrine disrupting property. In order to effectively degrade and mineralize DMP contaminated wastewater, a heterogeneous UVC/VUV-Fenton catalyst system was designed with the amendment of targeted design catalyst Fe 3 O 4 @CM-β-CD/rGO with core-shell like structure covered with loose convex folded lamellar. The optimum removal and mineralization efficiency of DMP were 98.6 % and 62.8 % in 30 min with 150 mg L−1 Fe 3 O 4 @CM-β-CD/rGO and 8 mmol L−1 H 2 O 2. This efficient and fast removal were attributed to a variety of photocatalytic oxidative active species •OH, •O 2 − and h+ with 59.6%, 29.1% and 9.9% contribution ratio, which mainly took effect on benzene ring open and side-chain fracture by oxidative, hydrolysis and hydrogen substitution determined by the rupture energy requirement from chemical bond in DMP. The target function of CM-β-CD in catalyst controlled the photo-electron generation rate and shorten mass transfer distance by the cladding lamellar, moreover, rGO accelerated the redox between Fe (II) and Fe (III) and electron transfer. The catalytic recovery and removal to DMP kept above 90 % after five recycles. This study provided an excellent performance catalyst and an effective photo-Fenton approach and for the treatment of endocrine disrupting wastewater. [Display omitted] • Nano catalysts Fe 3 O 4 coated by cross-linked lamellar CM-β-CD/rGO was prepared. • Removal efficiency and mineralization of DMP were 98.6% and 62.8% in 30min. • The.•OH, •O 2 −, and h+ contributed to 59.6%, 29.1% and 9.9% DMP removal. • DMP degnuradation pathways mediated by chemical structure and bond energy. • Catalytic recovery and DMP removal efficiency kept above 90 % after five recycles. [ABSTRACT FROM AUTHOR]