采用硝酸铝为铝源,碳酸铵为沉淀剂,聚乙二醇(PEG1450)为模板剂,合成廉价的有序介孔氧化铝(OMA)作为吸附剂载体。以2-氨基-2-甲基-1-丙醇(AMP)为氨基化表面修饰剂,对OMA采用过量浸渍法进行表面氨基化,制备一种高性能低成本的二氧化碳吸附...采用硝酸铝为铝源,碳酸铵为沉淀剂,聚乙二醇(PEG1450)为模板剂,合成廉价的有序介孔氧化铝(OMA)作为吸附剂载体。以2-氨基-2-甲基-1-丙醇(AMP)为氨基化表面修饰剂,对OMA采用过量浸渍法进行表面氨基化,制备一种高性能低成本的二氧化碳吸附剂OMA-AMP。通过BET法比表面积测定、X射线衍射(XRD)、透射电镜(TEM)、红外光谱(IR)等表征方法对改性前后吸附剂的比表面积、孔结构等特性进行表征,结果表明制备的OMA-AMP具有比表面积大、孔径分布窄、孔结构有序等特点。利用模拟烟道气,从浸渍时间、吸附床层温度、气体流量以及AMP浓度4个变量考察吸附剂的性能。结果表明,OMA经过质量分数为50%的AMP浸渍12 h,在吸附温度为70℃、气体流量为40 m L/min条件下,OMA-AMP对二氧化碳的吸附量高达84.15 mg/g;吸附剂吸附性能较稳定,再生容易且效果良好;吸附剂制备成本低廉,吸附效率高。该吸附剂可以解决在二氧化碳捕集技术中成本居高不下的问题,在工业上具有实际应用价值。展开更多
Zero-dimensional(0D)carbon dots exhibit excellent potential as a new oil-displacing agent for unconventional reservoir development.However,the difficulty in size/surface properties control and unclear mechanism hinder...Zero-dimensional(0D)carbon dots exhibit excellent potential as a new oil-displacing agent for unconventional reservoir development.However,the difficulty in size/surface properties control and unclear mechanism hinder their further applications.In this study,amino-modified carbon dots(am-CDs)for oil displacement were facilely synthesized through the rapid polymerization of D-glucose(D-Glc)and 3-aminopropyltriethoxysilane(APTES).The size of am-CDs could be precisely controlled by the reaction condition and quenching achieved by adjusting the pH value to neutral.The surface amine groups endow am-CDs with excellent hydrophilicity and dispersion stability.The 0.30 wt.%nanofluid based on am-CDs with an average size of 2.6±0.040 nm showed remarkable oil recovery efficiency(54.09%)without the addition of surfactant.The oil recovery efficiency of am-CDs is much higher than those of water flooding(30.25%),nano-SiO_(2) flooding(36.45%),and amino-free carbon dots(af-CDs)flooding(37.80%).Experimental and theoretical results reveal that am-CDs can be favorably adsorbed on the core surface to modulate the micro-scale wettability,changing the surface from oil-wet to relatively uniform water-wet.Meanwhile,am-CDs can effectively reduce the adhesion force between alkanes and sandstone surfaces,contributing to oil droplets peeling off and oil displacement.This study provides a new strategy for developing efficient carbon dots-based nanofluids for enhanced oil recovery.展开更多
文摘采用硝酸铝为铝源,碳酸铵为沉淀剂,聚乙二醇(PEG1450)为模板剂,合成廉价的有序介孔氧化铝(OMA)作为吸附剂载体。以2-氨基-2-甲基-1-丙醇(AMP)为氨基化表面修饰剂,对OMA采用过量浸渍法进行表面氨基化,制备一种高性能低成本的二氧化碳吸附剂OMA-AMP。通过BET法比表面积测定、X射线衍射(XRD)、透射电镜(TEM)、红外光谱(IR)等表征方法对改性前后吸附剂的比表面积、孔结构等特性进行表征,结果表明制备的OMA-AMP具有比表面积大、孔径分布窄、孔结构有序等特点。利用模拟烟道气,从浸渍时间、吸附床层温度、气体流量以及AMP浓度4个变量考察吸附剂的性能。结果表明,OMA经过质量分数为50%的AMP浸渍12 h,在吸附温度为70℃、气体流量为40 m L/min条件下,OMA-AMP对二氧化碳的吸附量高达84.15 mg/g;吸附剂吸附性能较稳定,再生容易且效果良好;吸附剂制备成本低廉,吸附效率高。该吸附剂可以解决在二氧化碳捕集技术中成本居高不下的问题,在工业上具有实际应用价值。
基金the National Key Research and Development Program of China(No.2019YFA0708700)the China National Petroleum Corporation Innovation Found(No.2021DQ02-0205).
文摘Zero-dimensional(0D)carbon dots exhibit excellent potential as a new oil-displacing agent for unconventional reservoir development.However,the difficulty in size/surface properties control and unclear mechanism hinder their further applications.In this study,amino-modified carbon dots(am-CDs)for oil displacement were facilely synthesized through the rapid polymerization of D-glucose(D-Glc)and 3-aminopropyltriethoxysilane(APTES).The size of am-CDs could be precisely controlled by the reaction condition and quenching achieved by adjusting the pH value to neutral.The surface amine groups endow am-CDs with excellent hydrophilicity and dispersion stability.The 0.30 wt.%nanofluid based on am-CDs with an average size of 2.6±0.040 nm showed remarkable oil recovery efficiency(54.09%)without the addition of surfactant.The oil recovery efficiency of am-CDs is much higher than those of water flooding(30.25%),nano-SiO_(2) flooding(36.45%),and amino-free carbon dots(af-CDs)flooding(37.80%).Experimental and theoretical results reveal that am-CDs can be favorably adsorbed on the core surface to modulate the micro-scale wettability,changing the surface from oil-wet to relatively uniform water-wet.Meanwhile,am-CDs can effectively reduce the adhesion force between alkanes and sandstone surfaces,contributing to oil droplets peeling off and oil displacement.This study provides a new strategy for developing efficient carbon dots-based nanofluids for enhanced oil recovery.
