Biomass-assisted synthesis of hierarchical zeolites for catalytic fast pyrolysis of lignocellulose biomass and waste plastic

This study developed a green production platform of renewable biofuel and valuable chemicals through optimization of catalytic pyrolysis and minimization of the related environmental concerns. A new post-synthetic methodology in zeolite modification successfully induced the formation of unique hierarchical HZSM-5 catalyst to further improve its functionality in the catalytic pyrolysis of lignocellulose biomass and waste plastic material. The first step of modification is via controlled alkaline treatment, which tailors mesopore formation while preserving crystallinity and acid properties of HZSM-5 zeolite. In the second step, the effluent from the alkaline treatment was subjected to crystallization condition in the presence of alkaline lignin to induce reassembly of the alkali-treated crystal subunits of HZSM-5. The surface properties of hierarchical HZSM-5 indicated the impact of lignin during the biomass-assisted zeolite synthesis, in which the conventional synthetic surfactant was replaced with natural organic materials. Additionally, the lignin used in catalyst preparation was acquired from the waste stream of an effective alkaline pretreatment of woody biomass in contribution to the valorization of waste by-product in bioenergy production. In the catalytic pyrolysis using the hierarchical HZSM-5 zeolites, high-quality liquid and gas products were obtained with better product yields compared to the parent HZSM-5. The excellent catalytic performances in the hierarchical HZSM-5 were also observed in the effectiveness of reducing coke formation on the catalyst. The secondary structures developed on the surface of HZSM-5 enabled catalytic cracking of bulky oxygenated intermediates and facilitated their accessibility to the active acid sites within the essential microporous zeolite framework for aromatization. Moreover, the larger pore openings and the intercrystalline mesopores in the hierarchical HZSM-5 were able to increase the diffusion flow of the reactants derived from the thermal decomposition of both lignocellulose biomass and plastic material. The optimization of process condition and enhancement of targeted products were further achieved in catalytic co-pyrolysis of lignocellulose biomass and plastic waste. Lastly, thermal degradation behavior of feedstock used in this study, and kinetic study of catalytic co-pyrolysis of lignocellulose and plastic mixture was evaluated with isoconversional methods

A conditional inducible JAK2V617F transgenic mouse model reveals myeloproliferative disease that is reversible upon switching off transgene expression

Aberrant activation of the JAK/STAT pathway is thought to be the critical event in the pathogenesis of the chronic myeloproliferative neoplasms (MPNs) polycythemia vera, essential thrombocythemia and primary myelofibrosis. The most frequent genetic alteration in these pathologies is the activating JAK2V617F mutation, and expression of the mutant gene in mouse models was shown to cause a phenotype resembling the human diseases. Given the body of genetic evidence, it has come as a sobering finding that JAK inhibitor therapy only modestly suppresses the JAK2V617F allele burden, despite showing clear benefits in terms of reducing splenomegaly and constitutional symptoms in patients. To gain a better understanding if JAK2V617F is required for maintenance of myeloproliferative disease once it has evolved, we generated a conditional inducible transgenic JAK2V617F mouse model using the SCL-tTA-2S tet-off system. Our model corroborates that expression of JAK2V617F in hematopoietic stem and progenitor cells recapitulates key hallmarks of human MPNs, and exhibits gender differences in disease manifestation. The disease was found to be transplantable, and importantly, reversible when transgenic JAK2V617F expression was switched off. Our results indicate that mutant JAK2V617F-specific inhibitors should result in profound disease modification by disabling the MPN clone bearing mutant JAK2

Enhancement of jet fuel range alkanes from co-feeding of lignocellulosic biomass with plastics via tandem catalytic conversions

Improvement of renewable alkanes for jet fuels from co-feed catalytic microwave-assisted pyrolysis and hydrogenation process. [Display omitted] •It is the first time to convert co-reactants of biomass and plastics into jet fuels.•There was a positive synergy for aromatics in catalytic microwave co-pyrolysis.•Well-fabricated catalysts were employed in respective processes.•Over 38% overall carbon yield of hydrogenated organics were gained.•∼90% selectivity toward jet fuel range alkanes was attained. Enhanced carbon yields of jet fuel range alkanes were manufactured from co-feeding of lignocellulosic biomass with plastics. The consecutive processes proceeded via the co-feed catalytic microwave-induced pyrolysis and hydrogenation process. In the co-feed catalytic microwave pyrolysis by using ZSM-5 as the catalyst, parent ZSM-5 fabricated by hydrothermal and calcined treatments contributed to the increase of surface area as well as the formation of more mesopores. Liquid organics with enhanced carbon yield (40.54%) were more principally lumped in the jet fuel range from the co-feed catalytic microwave pyrolysis performed at the catalytic temperature of 375°C with the plastics to biomass ratio of 0.75. To manufacture home-made Raney Ni catalyst, the BET surface area, pore surface area, and pore volume of the home-made Raney Ni catalyst were considerably improved when the Ni–Al alloy was dissolved by the NaOH solution. In the hydrogenation process, we observed the three species of raw organic derived from the co-feed catalytic microwave pyrolysis were almost completely converted into saturated hydrocarbons under a low-severity condition. The improved carbon yield (38.51%) of hydrogenated organics regarding co-reactants of biomass and plastics predominantly match jet fuels. In the hydrogenated organics, over 90% selectivity toward alkanes with the carbon number in the jet fuel range was attained. In this respect, these hydrogenated organics with high amounts of renewable cycloalkanes can be potentially served as high-density jet fuels or additives for blending with civilian jet fuels