以苯乙烯(St)、丙烯酸甲酯(MA)和丙烯酰胺(AM)为反应单体,偶氮二异丁腈为引发剂,采用反相微乳液聚合法,合成了成膜型纳米微乳液封堵剂。合成反应的最佳条件为:乳化剂复配比span80∶tween80=2∶1(质量比),反应单体配比为St∶MA∶AM=3∶1...以苯乙烯(St)、丙烯酸甲酯(MA)和丙烯酰胺(AM)为反应单体,偶氮二异丁腈为引发剂,采用反相微乳液聚合法,合成了成膜型纳米微乳液封堵剂。合成反应的最佳条件为:乳化剂复配比span80∶tween80=2∶1(质量比),反应单体配比为St∶MA∶AM=3∶1∶2(质量比),单体总浓度为25%,引发剂用量为2%,反应温度60℃,反应时间4 h。封堵剂的粒径中值为125.5 nm,满足对页岩微裂缝封堵的尺寸条件;热重分析表明,纳米封堵剂分解温度290℃左右,热稳定性好;在钻井液体系中加入3%的封堵剂,90℃热滚16 h后,粘度和切力变化不大,流变性较稳定,且其API滤失量仅为2 m L,FLHTHP(30 min)为6.0 m L,该纳米封堵剂性能优异,封堵效果好。展开更多
The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl acrylate.The structure and property of catalyst were ...The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl acrylate.The structure and property of catalyst were characterized by XRD,XPS,BET,Pyridine-IR,FT-IR,^(27)Al-MASNMR,NH_(3)-/CO_(2)-TPD and SEM.The correlation between structural features and acid-base properties was established,and the loading effect of the cesium species was investigated.Due to cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3),the weak-Ⅱacid and medium acid site densities and the product selectivity were improved.While the basic site densities of these catalysts were almost in proportion to the conversion of methyl acetate.The loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic performance.As a result,the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2%and 85%for methyl acrylate respectively.During the reaction,a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition,however,it could be regenerated by thermal treatment in the air atmosphere at 400℃.展开更多
文摘以苯乙烯(St)、丙烯酸甲酯(MA)和丙烯酰胺(AM)为反应单体,偶氮二异丁腈为引发剂,采用反相微乳液聚合法,合成了成膜型纳米微乳液封堵剂。合成反应的最佳条件为:乳化剂复配比span80∶tween80=2∶1(质量比),反应单体配比为St∶MA∶AM=3∶1∶2(质量比),单体总浓度为25%,引发剂用量为2%,反应温度60℃,反应时间4 h。封堵剂的粒径中值为125.5 nm,满足对页岩微裂缝封堵的尺寸条件;热重分析表明,纳米封堵剂分解温度290℃左右,热稳定性好;在钻井液体系中加入3%的封堵剂,90℃热滚16 h后,粘度和切力变化不大,流变性较稳定,且其API滤失量仅为2 m L,FLHTHP(30 min)为6.0 m L,该纳米封堵剂性能优异,封堵效果好。
基金supported by Key Research Program of Frontier Sciences(No.QYZDB-SSW-SLH022)National Natural Science Foundation of China(No.21676270,No.21878293,No.22178338)+1 种基金the Joint Fund of the Yulin University and the Dalian National-Laboratory for Clean Energy(Grant YLU-DNL Fund2021018)Foundation of State Key Laboratory of Highefficiency Utilization of Coal and Green Chemical Engineering(Grant No.2017-K08)。
文摘The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl acrylate.The structure and property of catalyst were characterized by XRD,XPS,BET,Pyridine-IR,FT-IR,^(27)Al-MASNMR,NH_(3)-/CO_(2)-TPD and SEM.The correlation between structural features and acid-base properties was established,and the loading effect of the cesium species was investigated.Due to cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3),the weak-Ⅱacid and medium acid site densities and the product selectivity were improved.While the basic site densities of these catalysts were almost in proportion to the conversion of methyl acetate.The loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic performance.As a result,the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2%and 85%for methyl acrylate respectively.During the reaction,a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition,however,it could be regenerated by thermal treatment in the air atmosphere at 400℃.
