Synthesis and characterization of aluminum and AI/REE pillared clays and supported palladium catalysts for benzene oxidation

Volatile organic compounds (VOCs) are considered as a major pollutant in indoor and outdoor air.More stringent environmental regulations have been implemented in order to reduce the VOC emissions.One of the techniques available for destructive removal of VOCs is catalytic oxidation.In the present work,Al/Rare Earths (REE: Y,Ce,La,Pr and Nd) pillared clays (PILCs) were used to support 0.2 wt.% of palladium for the complete oxidation of low concentration of benzene.The supports and catalysts were characterized by XRD,N2 adsorp-tion/desorption,FTIR spectroscopy,HRTEM and H2-TPR techniques.The results indicated that after Al and Al/REE pillaring,the basal spac-ing,SBET,Amic and Vmic of Al and AlREE-PILC had a considerable increase compared with those of Na-mmt.Activity tests of deep oxidation of benzene showed that the catalytic activity of Pd catalysts supported on Al and AlREE-PILC were much higher than that on initial clays,which was due to the fact that optimized structure of PILCs,such as large basal spacing,high SBET and porosity,improved Pd dispersion and increased the active sites of Pd.Especially for Pd/AlCe-PILC,the temperature of complete oxidation was about 280 oC,exhibiting the highest catalytic activity.     

Synthesis and characterization of aluminum and Al/REE pillared clays and supported palladium catalysts for benzene oxidation

Volatile organic compounds (VOCs) are considered as a major pollutant in indoor and outdoor air.More stringent environmental regulations have been implemented in order to reduce the VOC emissions.One of the techniques available for destructive removal of VOCs is catalytic oxidation.In the present work,Al/Rare Earths (REE: Y,Ce,La,Pr and Nd) pillared clays (PILCs) were used to support 0.2 wt.% of palladium for the complete oxidation of low concentration of benzene.The supports and catalysts were characterize...     

多孔壳聚糖微球/钯催化剂应用于水相Heck反应

以与壳聚糖具有一定相容性的水溶性高分子(聚乙二醇)为致孔剂,通过相转变法制得了多孔壳聚糖微球负载钯催化剂.利用扫描电镜、ICP-AES等对催化剂进行了表征.结果表明,所制备的壳聚糖基多孔微球具有高度开放的多孔结构,钯可有效的进入高分子微球的孔道中实现有效负载.该负载型催化剂能较好地催化丙烯酸丁酯与芳基碘系物的水相Hec...     

分散红356的合成工艺改进

对现有分散红356合成工艺进行了优化,以n(氢醌)∶n(扁桃酸)=1.2∶1投料,100℃反应30 min得缩合物2,再在等质量磷酸催化下与分批加入的等质量对丙氧基扁桃酸60℃缩合3 h得缩合物3,经温和氧化剂四氯苯醌氧化得标题化合物,总收率55%。     

壳聚糖／水溶性高分子共混膜相容性的预测与表征

高分子（聚乙烯醇和聚乙二醇）间的相容性,壳聚糖与极性水溶性高分子在溶液状态时,分子间相互吸引,相容性好,向本体转化而成膜时,CS／PVA体系比CS／PEG体系有更好的本体相容性。原因可归结为PEG不能像PVA一样提供足够多的极性基团与壳聚糖分子形成强烈相互作用,CS与PEG间的氢键强度要弱于CS与PVA间的氢键;另一个方面,PEG结晶能力很强,在由溶液转化为本体而成膜过程中,PEG分子自身之间易于形成较规整的结晶而逐渐使体系发生分相。     

正电子湮没技术在聚合物中的应用

介绍正电子湮没技术的实验方法、谱图解析方法，概述近几年该技术在聚合物领域的应用和研究进展。实验结果证明，正电子湮没技术是一种先进的材料微观结构—自由体积的探测和表征技术。同时，提出该技术在聚合物研究中使用测量参数o—ps强度I3计算自由体积分数所存在的问题。     

壳聚糖基多孔膜的制备方法进展

对壳聚糖基多孔膜制备的主要技术,相转化法、冷冻诱导相分离法、模板浸取法、聚合物辅助倒相法进行了评价,并着重探讨了在聚合物辅助倒相过程中,聚合物共混对的选择对多孔膜结构的影响。     

8-芳基-2-吡啶甲酰-1-萘胺的合成与表征

以1-萘胺为原料,与2-吡啶甲酸通过脱水缩合生成2-吡啶甲酰-1-萘胺反应底物。随后,在导向基团2-吡啶甲酰胺的螯合作用下,钯催化活化2-吡啶甲酰-1-萘胺的8-C—H键与芳基碘化物直接反应,一步及高区域选择性地合成标题化合物。产物结构均通过1HNMR、13CNMR和ESI-HRMS确证。     

环氧树脂纳米复合材料的制备和性能

通过对大量文献的调研，综述了国内外有关纳米改性环氧树脂复合材料的研究现状，讨论了插层聚合法，直接共混法以及溶胶-凝胶法制备环氧树脂基纳米复合材料的原理和材料结构特性及其宏观性能，并对该类材料的进一步研究和应用进行了评述。     

高冲聚苯乙烯-低密度聚乙烯的自由体积特征与其相溶性的关系

不同组成的高冲聚苯乙烯(HIPS)和低密度聚乙烯(LDPE)共混物的正电子湮没寿命谱被测量，结果表明HIPS和LDPE是不相溶共混物。在界面处，二组分的不相溶主要归因与一个组分没有足够大的自由体积孔穴尺寸容纳另一组分的侧基和分子链端基。另外，测量的自由体积分数产生的负偏差被认为主要由最长寿命强度I3所引起。