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On the basis of the Gibbs free energy minimization principle, the dry autothermal reforming performance of crude glycerol in situ hydrogen separation is investigated via thermodynamic analysis. The impact of hydrogen separation fraction on gas composition in product, carbon formation and reaction heat is studied. It can be found that the hydrogen separation promotes the hydrogen production and hinders methane formation. The hydrogen removal is selective to the reduction of carbon deposition, which improves the carbon formation at a low feed CO 2 to glycerol molar ratio and the impact is reverse for high feed CO 2 to glycerol molar ratio. When the reaction temperature varies from 850 K to 900 K, the required oxygen to glycerol molar ratio of thermal neutral condition is obviously increased from 0.15 to 0.4 with hydrogen removal. Meanwhile, the glycerol impurities evaluation indicates that the syngas yield is significantly reduced with the increase of the glycerol impurities. At a high temperature, the hydrogen removal is in favor of the achievement of autothermal process.

The performance of glycerol autothermal reforming in membrane reactors with in situ hydrogen separation is investigated by means of thermodynamic analysis based on Gibbs free energy minimization method. The influence of operational parameters such as reaction temperatures and oxygen to glycerol ratios under different hydrogen separation fractions is evaluated. It is found that reaction temperatures have a more significant impact on hydrogen yield compared to other parameters. The hydrogen removal can promote the hydrogen production obviously and reduce the required temperature of the maximum hydrogen yield. The hydrogen separation effect on carbon formation is discussed. Meanwhile, the performance of ethanol–glycerol mixture autothermal reforming process is also analyzed.

Glycerol reforming technology provides an efficient means for the hydrogen production industry and the utilization of biodiesel-derived crude glycerol. Fluidized bed reactors have potential in interphase mass/heat transfer and mitigating catalyst deactivation. In this study, computational fluid dynamics is used to investigate the performance of glycerol steam reforming in a fluidized bed system. A bubble-structure-dependent drag model is implemented into the two-fluid model to reflect the bubble effect. A three-dimensional simulation is conducted. The model is verified by experimental data. By analysis of the influence of operating conditions and property parameters, it is found that the reaction temperature plays a vital role in the enhancement of hydrogen production.

Zinc complexes L2Zn and LZnX were prepared by template synthesis from ZnX2, N1,N1-dimethylbenzene-1,2-diamine and substituted salicylaldehyde (SA). A systematic exploration of this synthetic route revealed the subtle role of choice of Zn source and SA substitution pattern on the reaction stoichiometry and enabled synthesis of pure Zn complexes. Use of poorly coordinating counterions (such as CF3SO3−) and apolar substituents on the SA component favours formation of pentacoordinate L2Zn, while more coordinating counterions tend to produce LZnX, (LZnX)2 or even binuclear LZn(O2CR)Zn(O2CR)2 not reported before. The complexes (LZnX)2 and LZn(O2CR)·Zn(O2CR)2 (L = L2 or L4) could be activated with BnOH/LiMe for ring-opening polymerization of e-caprolactone; bis(ligand) complexes L2Zn show low or vanishing activity when activated either by BnOH or BnOH/LiMe.

Polystyrene (PS) nanoparticles coated by BSA, hereafter denoted as PS/BSA, were prepared and chemically immobilized for the first time onto a capillary inner wall for open-tubular CEC (OTCEC). EOF and scanning electron micrography were used to characterize the prepared nanoparticle-coated capillaries. To investigate the performance of the prepared columns in OTCEC, chiral separation of d,l-tryptophan (dl-Trp) was performed in monolayer BSA-modified capillary and PS/BSA nanoparticle-coated columns. The results indicated that the nanoparticle-modified column afforded a higher resolution compared with the monolayer type. Rapid enantioseparation of dl-Trp (within 3 min) was achieved with the PS/BSA-immobilized column using an electroosmotic pump-assisted CEC. Enantiomer separations of other compounds like dl-tyrosine and warfarin were also achieved with the column. Besides, run-to-run and column-to-column repeatabilities of the PS/BSA-coated column in the chiral separation were systematically introduced.