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In this study, a series of Na–Zr/TiO2 photocatalysts with different Na contents were synthesized via the sol–gel process. The characterization of the materials showed that Na addition facilitates the maintenance of anatase and excess Na led to particle size increases because of the formation of Na2Ti3O7. The XPS results suggested that Na loading can increase the number of oxygen vacancies, leading to more abundant surface hydroxyl groups. The enhanced photocatalytic activities under visible light irradiation can be attributed to a decreasing band gap and increasing oxygen vacancies. The efficiency of the Na–Zr/TiO2 samples was investigated by the degradation of formaldehyde under visible light. A high degradation rate of formaldehyde of approximately 96.6% was obtained with 2.5 mol % Na added to the Zr/TiO2 samples.

The purification of lignocellulosic hydrolysate has great practical significance in the field of bioenergy and biorefinery. In this study, the effects of textural properties of styrene-divinylbenze...

Acid-activated attapulgite (H+-ATP)-supported NiCoB amorphous alloy catalysts were applied to the selective hydrogenation of furfural (FUR) to furfuryl alcohol (FA). The reduction process between metallic ions impregnated in/on H+-ATP and BH4– is important to modify the textural properties of catalyst, because of the secondary activation of H+-ATP. The enhancement of interaction between H+-ATP and NiCoB particles promotes the dispersion of NiCoB amorphous alloy. Under the optimal conditions (140 °C, 3 MPa H2, 800 rpm, 3.8 wt % of NiCoB active component with respect to FUR), FUR conversion of 91.3%, and FA selectivity of 82.0% were achieved over the best catalyst (20%NiCoB/H+-ATP). Moreover, the catalyst was recycled six times and showed an increase of 3.9% in FUR conversion and 8.2% in FA selectivity, which might be due to the newly generated Co–Ni alloy active site. The low-cost nature of H+-ATP makes the supported NiCoB catalyst a potential catalyst for the industrial production of FA.

A novel linear-chain polyamide charring agent named poly(piperazinyl oxalamide) (PPOA) was prepared successfully. Thermogravimetric analysis (TGA) proved that PPOA had a charring capability that was better than those of traditional polyamide charring agents. After incorporation of PPOA into ethylene-vinyl acetate copolymer/ammonium polyphosphate (EVA/APP), the flame retardancy of EVA/APP was dramatically improved. At 25.0 wt % APP/PPOA(3:1), the OI value of the EVA/APP/PPOA system was 31.5%; its UL-94 rating was V-0. Both the peak of heat release rate (PHRR) and the peak of smoke production rate (peak SPR) for the EVA/APP/PPOA system decreased remarkably compared with that of EVA containing 25.0 wt % APP. The analysis of the charring mechanism of PPOA demonstrated that abundant heterocyclic aromatic structures were formed during the decomposition of PPOA, which endowed the PPOA with excellent charring capability and resulted in the low risk of combustion of the EVA/APP/PPOA system.

To give an insight into the kinetics of microbial oil fermentation with lignocellulosic hydrolysate as substrate, lipid production by Trichosporon fermentans in rice straw hydrolysate was investigated in a 5 L fermentor. For comparison, fermentation in its simulated medium was also performed to evaluate the effect of inhibitors present in the rice straw hydrolysate on the cell growth and lipid accumulation of T. fermentans. The optimum fermentation time, maximum biomass, and lipid content of T. fermentans in the rice straw hydrolysate were 10.5 days, 28.6 g/L, and 43.9%, respectively, while the corresponding values in the simulated medium were 8.5 days, 27.0 g/L, and 65.0%, respectively, indicating that the inhibitors in the rice straw hydrolysate did show some inhibition on the cell growth and lipid accumulation of T. fermentans. Kinetic models of lipid fermentation with T. fermentans showed the maximum specific growth rate and the correlation coefficient of lipid synthesis to cell growth in the rice straw hydrolysate were 0.40 and 0.51, respectively, which are much lower than those in the simulated medium (0.58 and 0.73). To better understand the influential mechanism of inhibitors in the rice straw hydrolysate on the growth and lipid accumulation of T. fermentans, the physiological and biochemical changes of cells in the fermentation were further investigated. The reduced activities of adenosine triphosphate (ATP) citrate lyase, malic enzyme, and xylose reductase, and the elongation of cells at the beginning of fermentation, partly account for the inhibitory effect of inhibitors in the rice straw hydrolysate.

Composite asymmetric Pd–Au membranes were prepared on porous Inconel and Hastelloy tubular supports by electroless deposition and galvanic displacement techniques and tested both before and after Au deposition in pure H2 atmosphere. The final membranes with average Au bulk content up to 16.7 wt % were 9–15 μm thick and showed H2/He ideal selectivities in excess of 900 for the entire period of their characterization. The annealing of the as-prepared membranes was conducted through the coating and diffusion mechanism in He and H2 atmospheres at 500 °C. The annealing conditions were chosen after nonisothermal and isothermal HT-XRD studies were carried out on Pd–Au coupons prepared with the same techniques used for the membranes fabrication. After the formation of the Pd–Au layer, the membranes showed steady H2 flux and stable Au gradient on the membrane top layer. Comparisons between permeance for Pd–Au and pure Pd membranes indicated that the membranes with an average Au bulk content of 4.5 and 5.4 wt % had...