钴钼基水煤气变换催化剂及其催化反应工艺

介绍了国内外CO变换催化剂的发展及其在不同变换工艺中的应用,阐述了Co-M o基催化剂的催化机理与硫化方法。通过综合分析中温变换、中温变换串联低温变换、中温变换串联两段低温变换和全程低温变换4种代表性的工艺流程,提出了高效节能型的全程低温变换工艺将是变换技术的发展方向,开发适应全程低温变换工艺的高活性和高稳定性的Co-M o基变换催化剂及其预硫化技术是今后的主要研究目标

不同气氛下热处理对CO甲烷化催化剂性能的影响

采用液相包裹法制备了Ni/Al2O3耐高温甲烷化催化剂,并分别在静态空气、动态氮气及动态空气气氛条件下程序升温到550oC,恒温煅烧,得到不同气氛下热处理的三种催化剂。通过BET,H2-TPR,XPS等一系列的表征分析结果显示,经过动态气氛下煅烧的催化剂在高温和低温都具备良好的活性,其具有较大的比表面积,且流动性的气体可以有效的降低催化剂中镍与载体的结合力,主要表现在氧化镍的化学位能降低0.5eV,镍更易于还原

Effects of composite oxide supports on catalytic performance of Ni-based catalysts for CO methanation

采用改良的粉末混合法制备了系列经过其它金属氧化物改性的nIO/Al2O3催化剂,并运用X射线衍射、透射电子显微镜、n2低温物理吸附-脱附、程序升温还原、程序升温脱附、拉曼以及X射线光电子能谱对催化剂进行了表征.结果显示,在300~700OC经MgO修饰的nIO/Al2O3催化剂上CO甲烷化反应活性比nIO/zrO2-Al2O3和nIO/SIO2-Al2O3的高.另一金属氧化物的加入削弱了nIO/Al2O3催化剂中nI-Al间相互作用,形成更多的活性nI物种,从而促进了反应的进行.Metal-oxide-modified NiO/Al2O3 catalysts for methanation of CO were prepared using a modified grinding-mixing method and characterized using X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption isotherms, temperature-programmed reduction by H2, temperature-programmed desorption by H2, Raman spectroscopy, and X-ray photoelectron spectroscopy.The results show that the activity of an MgO-modified NiO/Al2O3 catalyst is better than those of NiO/ZrO2-Al2O3 and NiO/SiO2-Al2O3 in the reaction temperature range 300–700 °C.The incorporation of a metal oxide into NiO/Al2O3 was found to weaken Ni–Al interactions, leading to generation of large numbers of active Ni species, and this was confirmed to be responsible for the improvement in the performances of the catalysts in the methanation reaction.supportedbytheNationalBasicResearchProgramofChina(973Program;2010CB226903)~

负载液pH对Co-Mo/MgO-Al2O3催化剂水煤气变换性能的影响

以MgO-Al2O3复合氧化物为载体,调节负载液的pH=3,7,10,负载Co-Mo活性组分制备了耐硫水煤气变换Co-Mo/MgO-Al2O 3系列催化剂,并进行了催化性能评价实验。采用H2-TPR和激光拉曼光谱（LRS）方法对系列催化剂进行了表征,考察了负载液的酸碱性对Co-Mo活性组分在MgO-Al2O3复合氧化物载体分散和表面物种形成的影响。实验结果表明,随着不同pH负载液的加入,载体表面的电化性质发生变化,从而影响载体与Co-Mo活性组分、Co和Mo组分之间的相互作用,改变了活性组分Co和Mo在载体表面的分散度和表面物种的形态;当负载液pH=3,7时,Mo与载体的相互作用较强,而当负载液pH=10时,在氧化态催化剂中有利于形成八面体结构Mo物种,经过升温硫化后,催化剂表面形成更多OxMo S2-4-x和Mo S2物种

载体焙烧温度对Co-Mo/MgO-Al_2O_3变换催化剂性能的影响

通过X射线衍射、N2吸附-脱附、程序升温脱附、程序升温还原和电子顺磁共振方法研究了焙烧温度对MgO-Al2O3载体物化结构和Co-Mo/MgO-Al2O3变换催化剂性能的影响.结果表明,在600～800oC范围内焙烧的复合氧化物以MgAl2O4-xMgO-yAl2O3无定形形式存在,载体表面存在较多的中强酸-碱位,相应的负载催化剂具有较高的水煤气变换活性.在氧化态催化剂中存在较多八面体结构的Mo物种,而硫化态催化剂中含有较多氧硫包围的Mo物种.这些钼物种与催化剂的活性紧密相关

焙烧温度对镁铝复合氧化物载体性能的影响

采用混合固相反应法制备了一系列不同焙烧温度的镁铝复合氧化物载体,并负载Co-Mo活性组分制备了Co-Mo/MgO-Al2O3催化剂;通过扫描电子显微镜、傅里叶变换红外光谱、N2吸附-脱附、X射线衍射、热分析和质量滴定等方法考察了焙烧温度对载体性能的影响,并评价了Co-Mo/MgO-Al2O3催化剂在水煤气变换反应中的活性。实验结果表明,500~800℃焙烧的镁铝复合氧化物载体以MgAl2O4.xMgO.yAl2O3无定形复合氧化物形式存在,900~1 300℃焙烧的镁铝复合氧化物载体转变为MgAl2O4尖晶石;600~800℃焙烧的镁铝复合氧化物载体具有适宜的比表面积和孔结构,有较高的零电荷点,有利于Co-Mo活性组分的吸附和分散,以其为载体制备的Co-Mo/Al2O3-MgO催化剂具有很高的活性

XH-2/3型组合式耐硫变换催化剂的试生产和工业应用

XH-3型催化剂是在XH-2型催化剂(Co-Mo-K/γ-Al2O3)的基础上引入第3种活性组分钨而制成的。通过活性评价和工业侧线试验,结果表明XH-2、XH-3型催化剂在最佳活性温区和耐热性能方面各具特色,可以进行组合填装使用。12 t XH-2/3型组合式耐硫变换催化剂已经成功应用于合成氨的变换工序中,能够达到生产工艺的要求

Effect of Calcination Temperature of Support on the Performance of Co-Mo/MgO-Al2O3 Water-Gas Shift Catalyst

The effect of calcination temperature of the MgO-Al2O3 mixed oxide Support on the physicochemical properties of the support and the performance of the Co-Mo-based water-gas shift catalyst was Studied by means of X-ray diffraction, N-2 adsorption-desorption temperature-programmed desorption, temperature-programmed reduction, and electron paramagnetic resonance. The activity testing results showed that the catalysts with the mixed oxide supports calcined at 600-800 degrees C exhibited high activity for the reaction. The physicochemical characterization results indicated that MgO-Al2O3 mixed oxide supports calcined at 600-900 degrees C existed as amorphous compound MgAl2O4-xMgo-yAl(2)O(3), Oil which more middle strength acid-base sites were formed. For the Co-Mo/MgO-Al2O3 catalysts in oxidation state, more octahedral Mo species were found, while more oxysulfo-Mo5+ species were detected oil the sulfurized catalysts. These species were closely related to the catalytic activity

Trial production and industrial sidetrack test of the XH-1 type of potassium-free sulfur-tolerant shift catalyst

作者简介: 连奕新( 1971-),男,博士生;杨意泉(1944- ),男, 硕士,研究员,博士生导师,主要从事工业催化方面的研究, 通讯联系人,0592-2186368, [email protected]。[中文文摘]以镁铝尖晶石复合材料为载体,采用浸渍钴钼活性组分无煅烧技术,中试制备出新型XH-1无钾耐硫变换催化剂。对该催化剂进行实验室活性评价和6个月的工业侧线试验,结果表明:XH-1型催化剂结构稳定、机械强度高;在中压(2.0MPa)、低汽气比(0.3~0.6)的反应条件下,催化活性优于国内外同类产品;在高压(≥3.0 MPa)、高汽气比(≥1.0)条件下催化性能与同类产品相当,符合高、中压各种变换工艺条件对催化剂性能的要求。[英文文摘]New XH-1 type of potassium-free sulfur-tolerant water gas shift catalyst was trial produced on a pilot scale by the impregnation of Co-Mo active composition on the complex support of magnalium-alumina spinel without calcination.The results of both the evaluation in the laboratory and the industrial sidetrack test in a period of six months showed that the XH-1 type of catalyst had higher activity in comparison with the same type of products made in inland and overseas under medium pressure(2.0 MPa) and at ow steamtogas ratio( 0.3-0.6),but the same activity under high pressure (3.0MPa) and at high steamtogas ratio(≥1.0).Moreover the XH-1 type of catalyst was found to have stable construction and high mechanical strength. The catalyst was suitable for different shift technology conditions of high and medium pressure.厦门市企业创新基金计划项目(3502Z20031082