采用等体积浸渍法制备了2%Pt/10%MoO_3-ZrO_2双功能固体催化剂,通过XRD、BET、CO化学吸附、NH3-TPD等手段对催化剂组成、结构和性质进行了表征,并以乙二醇为模型分子研究了2%Pt/10%MoO_3-ZrO_2催化下多元醇水相加氢脱氧过程中的反应动...采用等体积浸渍法制备了2%Pt/10%MoO_3-ZrO_2双功能固体催化剂,通过XRD、BET、CO化学吸附、NH3-TPD等手段对催化剂组成、结构和性质进行了表征,并以乙二醇为模型分子研究了2%Pt/10%MoO_3-ZrO_2催化下多元醇水相加氢脱氧过程中的反应动力学特性。结果表明,2%Pt/10%MoO_3-ZrO_2对乙二醇的水相加氢脱氧(HDO)反应具有较好的催化活性和选择性,乙二醇水相HDO反应对乙二醇服从一级反应动力学规律,反应活化能为17.2 k J/mol,与其竞争的重整反应的活化能为111.4 k J/mol。较低的反应温度更有利于提高乙二醇水相HDO的选择性,适宜的反应条件为210℃,5.5 MPa H2,催化剂用量为乙二醇的10%。在此条件下,乙二醇转化率12.5%,HDO产物选择性96.1%。展开更多
A nanoporous MoO3/ZrO2 mixed oxide was hydrothermally synthesized by hydrolyzing zirconium isopropoxide in the presence of a cationic surfactant, eetyltrimethylammonium bromide（CTAB）. The crystal structure and the a...A nanoporous MoO3/ZrO2 mixed oxide was hydrothermally synthesized by hydrolyzing zirconium isopropoxide in the presence of a cationic surfactant, eetyltrimethylammonium bromide（CTAB）. The crystal structure and the acidity of the obtained nanoporous MoO3/ZrO2 mixed oxide were determined by means of XRD, N2 adsorption-desorption and NH3-TPD, respectively. The isobutane/butene alkylation over the MoO3/ZrO2 catalyst was carried out in a fixed bed reactor. The results reveal that ZrO2 in MoO3/ZrO2 exists mainly in the tetragonal phase, and the catalyst samples possess large specific surface areas as well as moderate acidity for isobutane/butene alkylation. Compared with samples prepared by impregnation and sol-gel processes, MoO3/ZrO2 mixed oxide samples prepared in this work have a better catalytic activity.展开更多
以硝酸为溶剂,氢氧化钠为沉淀剂,采用共沉淀法,制备了一系列不同M O含量的Cu-M O O3-ZrO2催化剂,并采用X射线粉末衍射(XRD)、N2吸脱附(BET)以及程序升温还原(TPR)对催化剂结构进行了表征.研究该催化剂在二乙醇胺脱氢合成亚氨基二乙酸反...以硝酸为溶剂,氢氧化钠为沉淀剂,采用共沉淀法,制备了一系列不同M O含量的Cu-M O O3-ZrO2催化剂,并采用X射线粉末衍射(XRD)、N2吸脱附(BET)以及程序升温还原(TPR)对催化剂结构进行了表征.研究该催化剂在二乙醇胺脱氢合成亚氨基二乙酸反应中的催化性能,考察Cu-M O O3-ZrO2的反应条件对二乙醇胺脱氢反应性能的影响.结果表明,共沉淀制备的Cu-M O O3-ZrO2催化剂(摩尔比为Cu∶M O∶Zr=3∶5∶2),具有优良的催化性能:在温度165℃、压力0.5 MPa,反应4 h条件下,二乙醇胺转化率达到100%,亚氨基二乙酸的选择性为96.3%,催化剂重复使用12次活性无明显下降.表征结果表明,添加适量的M O助剂有利于促进催化剂中CuO的还原,增大催化剂的比表面积和孔容,降低催化剂的还原温度,并显著提高催化剂的催化活性.展开更多
In this study, different methods were used to prepare MoO3/ZrO2 catalysts for sulfur resistant methanation reaction. It was found that MoO3/ZrO2 catalyst prepared by one-step co-precipitation method achieved high meth...In this study, different methods were used to prepare MoO3/ZrO2 catalysts for sulfur resistant methanation reaction. It was found that MoO3/ZrO2 catalyst prepared by one-step co-precipitation method achieved high methanation performance. CO conversion could reach up to 90% on 25 wt% MoO3/ZrO2 catalyst, much higher than that on the conventional 25 wt% MoO3/Al2O3 catalyst. The Mo-based catalysts were characterized by XRF, XRD, Raman, BET, TEM and H2-TPR etc. It was found that MoO3 particles were highly dispersed on ZrO2 support for 25 wt% MoO3/ZrO2 catalyst prepared at 65-85℃ because of its relatively larger pore size, which contributed to a high CO conversion. Meanwhile, when MoO3 loading exceeded the monolayer coverage, the formed crystalline MoO3 and ZrM020g might block the micropores of the catalyst and make the methanation activity declined. These results are useful for preparing highly efficient catalyst for CO methanation process.展开更多
文摘采用等体积浸渍法制备了2%Pt/10%MoO_3-ZrO_2双功能固体催化剂,通过XRD、BET、CO化学吸附、NH3-TPD等手段对催化剂组成、结构和性质进行了表征,并以乙二醇为模型分子研究了2%Pt/10%MoO_3-ZrO_2催化下多元醇水相加氢脱氧过程中的反应动力学特性。结果表明,2%Pt/10%MoO_3-ZrO_2对乙二醇的水相加氢脱氧(HDO)反应具有较好的催化活性和选择性,乙二醇水相HDO反应对乙二醇服从一级反应动力学规律,反应活化能为17.2 k J/mol,与其竞争的重整反应的活化能为111.4 k J/mol。较低的反应温度更有利于提高乙二醇水相HDO的选择性,适宜的反应条件为210℃,5.5 MPa H2,催化剂用量为乙二醇的10%。在此条件下,乙二醇转化率12.5%,HDO产物选择性96.1%。
文摘A nanoporous MoO3/ZrO2 mixed oxide was hydrothermally synthesized by hydrolyzing zirconium isopropoxide in the presence of a cationic surfactant, eetyltrimethylammonium bromide（CTAB）. The crystal structure and the acidity of the obtained nanoporous MoO3/ZrO2 mixed oxide were determined by means of XRD, N2 adsorption-desorption and NH3-TPD, respectively. The isobutane/butene alkylation over the MoO3/ZrO2 catalyst was carried out in a fixed bed reactor. The results reveal that ZrO2 in MoO3/ZrO2 exists mainly in the tetragonal phase, and the catalyst samples possess large specific surface areas as well as moderate acidity for isobutane/butene alkylation. Compared with samples prepared by impregnation and sol-gel processes, MoO3/ZrO2 mixed oxide samples prepared in this work have a better catalytic activity.
文摘以硝酸为溶剂,氢氧化钠为沉淀剂,采用共沉淀法,制备了一系列不同M O含量的Cu-M O O3-ZrO2催化剂,并采用X射线粉末衍射(XRD)、N2吸脱附(BET)以及程序升温还原(TPR)对催化剂结构进行了表征.研究该催化剂在二乙醇胺脱氢合成亚氨基二乙酸反应中的催化性能,考察Cu-M O O3-ZrO2的反应条件对二乙醇胺脱氢反应性能的影响.结果表明,共沉淀制备的Cu-M O O3-ZrO2催化剂(摩尔比为Cu∶M O∶Zr=3∶5∶2),具有优良的催化性能:在温度165℃、压力0.5 MPa,反应4 h条件下,二乙醇胺转化率达到100%,亚氨基二乙酸的选择性为96.3%,催化剂重复使用12次活性无明显下降.表征结果表明,添加适量的M O助剂有利于促进催化剂中CuO的还原,增大催化剂的比表面积和孔容,降低催化剂的还原温度,并显著提高催化剂的催化活性.
基金supported by the Tianjin Municipal Science and Technology Commission(14JCZDJC37500)
文摘In this study, different methods were used to prepare MoO3/ZrO2 catalysts for sulfur resistant methanation reaction. It was found that MoO3/ZrO2 catalyst prepared by one-step co-precipitation method achieved high methanation performance. CO conversion could reach up to 90% on 25 wt% MoO3/ZrO2 catalyst, much higher than that on the conventional 25 wt% MoO3/Al2O3 catalyst. The Mo-based catalysts were characterized by XRF, XRD, Raman, BET, TEM and H2-TPR etc. It was found that MoO3 particles were highly dispersed on ZrO2 support for 25 wt% MoO3/ZrO2 catalyst prepared at 65-85℃ because of its relatively larger pore size, which contributed to a high CO conversion. Meanwhile, when MoO3 loading exceeded the monolayer coverage, the formed crystalline MoO3 and ZrM020g might block the micropores of the catalyst and make the methanation activity declined. These results are useful for preparing highly efficient catalyst for CO methanation process.
