Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylat...Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation.展开更多
为深入探索老山芹种子休眠机理,以老山芹层积前后种子为研究对象,采用气相色谱-飞行时间质谱联用技术(gas chromatography-time of flight mass spectrometry,GC-TOF/MS)对其非层积种子(non-lamellarized seeds,NS)和层积后达到发芽状...为深入探索老山芹种子休眠机理,以老山芹层积前后种子为研究对象,采用气相色谱-飞行时间质谱联用技术(gas chromatography-time of flight mass spectrometry,GC-TOF/MS)对其非层积种子(non-lamellarized seeds,NS)和层积后达到发芽状态种子(germination seeds,GS)的差异代谢物进行分析。结果表明,共检测到995种代谢产物,NS和GS的代谢物存在明显分离,差异代谢物有126种,其中极显著差异代谢物75种,包括35种上调,40种下调。对极显著差异代谢物所在代谢通路分析表明,涉及10条关键代谢通路。和弦图分析表明,差异代谢物中脂质类化合物(含类脂分子)与苯类化合物呈极显著正相关;苯丙烷类化合物(含聚酮类化合物)与有机氧类化合物呈极显著负相关。以上研究结果为探索老山芹种子成熟后萌发提供了代谢组学理论基础,为更好地研究老山芹种子后成熟及休眠机制提供了依据和支撑。展开更多
基金Supported by National Key Research&Development Program of China (2022YFB4201800)Key Program of National Natural Science Foundation of China (52130610)。
文摘Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation.
文摘为深入探索老山芹种子休眠机理,以老山芹层积前后种子为研究对象,采用气相色谱-飞行时间质谱联用技术(gas chromatography-time of flight mass spectrometry,GC-TOF/MS)对其非层积种子(non-lamellarized seeds,NS)和层积后达到发芽状态种子(germination seeds,GS)的差异代谢物进行分析。结果表明,共检测到995种代谢产物,NS和GS的代谢物存在明显分离,差异代谢物有126种,其中极显著差异代谢物75种,包括35种上调,40种下调。对极显著差异代谢物所在代谢通路分析表明,涉及10条关键代谢通路。和弦图分析表明,差异代谢物中脂质类化合物(含类脂分子)与苯类化合物呈极显著正相关;苯丙烷类化合物(含聚酮类化合物)与有机氧类化合物呈极显著负相关。以上研究结果为探索老山芹种子成熟后萌发提供了代谢组学理论基础,为更好地研究老山芹种子后成熟及休眠机制提供了依据和支撑。