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1.
采用水热法合成了小粒径、具有介孔结构的SAPO-11分子筛.采用浸渍法制备了不同Ni负载量的Ni/SAPO-11催化剂.并采用X射线衍射,扫描电镜,N_2物理吸附-脱附,NH_3程序升温脱附,热重和H_2化学吸附技术对该类催化剂的物理化学性质进行了详细表征.结果表明,SAPO-11较大表面积和介孔结构可分散Ni,使得Ni粒子尺寸较小.在棕榈油加氢脱氧制备液体烃类燃料反应中,液体烷烃产物由相关脂肪酸中间产物的直接加氢脱氧和脱羰-加氢脱氧两种途径产生.Ni/SAPO-11催化剂的弱/中强酸性质及其匹配的金属-酸双功能可显著抑制积炭反应,提高催化剂的寿命,液体烷烃收率高达70%,异构烷烃选择性超过80%.  相似文献   

2.
采用过量浸渍法制备了不同镍负载量的Ni P/SAPO-11催化剂,并用N2吸附-脱附、吡啶红外光谱、NH3-TPD、H2-TPR等技术对催化剂的物理化学性能进行了测试。脂肪酸甲酯催化加氢脱氧及产物异构化反应在固定床反应器上进行,液体产品分别用GC-MS和GC进行定性和定量分析。结果表明,在温度为340℃,压力为2.0 MPa,氢气流量为60 m L/min,重时空速为2.5 h-1的操作条件下,当Ni负载量为3%(质量分数)时,原料转化率可以达到97.8%,C15-18的收率84.5%,异构化率14.0%。  相似文献   

3.
在固定床反应器中,以大豆油为模型原料,研究了反应温度、压力、氢油比和空速等条件对Pt/SAPO-11催化油脂一步加氢制异构烷烃反应的影响,并分析了反应中间产物、气体产物(CO,CO2)及烷烃终产物的变化趋势. 结果表明,高温、低压或低氢油比可抑制酯、羧酸和醛的氢解以及醇的生成,促进油脂脱氧选择性地向脱羧和脱羰方向进行;异构烷烃收率随温度升高或空速减小而先增加后下降,但反应压力和氢油比的影响不大. 另外,对油脂一步加氢过程可能的反应历程进行了讨论.  相似文献   

4.
通过浸渍法制备了Pt/SAPO-11催化剂,分步浸渍法制备了Ni-Pt/SAPO-11双金属催化剂。通过X射线衍射、低温氮物理吸附、氨程序升温脱附和吡啶吸附红外等手段对所得样品进行了表征。结果表明,助剂Ni的引入导致了催化剂的比表面积和孔容降低,同时,催化剂的B酸量、L酸量及总酸量均有所下降。在340℃时对正庚烷的临氢异构化反应中,当Pt含量0.2wt%时,Pt/SAPO-11催化剂的正庚烷转化率为45%,C7异构体收率为43%;而当Pt含量0.2wt%,同时Ni含量为0.2wt%时,Ni-Pt/SAPO-11催化剂的正庚烷转化率提高至72%,C7异构体收率提高至60%。  相似文献   

5.
分别以Al2O3-SiO2,Al2O3-TiO2,TiO2-SiO2和TiO2-ZrO2双金属氧化物为载体研究Ni基催化剂的愈创木酚加氢脱氧性能. 重点考察了催化剂载体、溶剂种类、反应温度和压力对愈创木酚转化率及产物选择性的影响,并对催化剂的抗积碳性能、重复利用性能和愈创木酚加氢脱氧反应机理进行了探讨. 通过BET(Brunauer-Emmett-Teller)比表面积、X射线衍射(XRD)、NH3程序升温脱附(NH3-TPD)和H2程序升温还原(H2-TPR)等表征手段对催化剂的比表面积、物相结构、表面酸性、可还原性能进行了表征. 结果表明,Ni/TiO2-ZrO2催化性能相对较优. 在300 ℃、初始氢压4 MPa、以十氢萘为溶剂的最佳反应条件下,愈创木酚的转化率为100%,环己烷选择性高达86.4%. 该催化剂还具有抗积碳性能,反应后的催化剂上仅检测到3.2%(质量分数)的积碳量.  相似文献   

6.
Ni(Co)-W-B非晶态催化剂的制备和加氢脱氧性能研究   总被引:1,自引:0,他引:1  
采用化学还原法制备出非晶态催化剂Ni-W-B和Co-W-B,用BET、XRD和XPS对催化剂进行表征分析,以对甲基苯酚为模型化合物研究了两种催化剂的加氢脱氧性能。结果表明,所制备的两种催化剂均为非晶态结构,两种催化剂在对甲基苯酚的加氢脱氧反应中都显示出较好的脱氧活性。在相对低温523 K下,Ni-W-B催化剂显示较高的加氢活性,转化率达到100.0%,对甲基环己醇的选择性为55.1%,脱氧选择性只有44.1%,而Co-W-B催化剂显示出较高的脱氧活性,脱氧选择性达到93.1%,这主要是由于催化剂的表面不同价态元素组成含量引起的。在573 K和4.0 MPa下,催化对甲基苯酚的加氢脱氧反应的转化率和脱氧选择性都能达到100%。  相似文献   

7.
采用创新方法制备的ZrO2、TiO2担载氧化铁催化剂在二氧化碳加氢制低碳烃反应中显示出良好的催化活性和产物选择性,由15wt?/ZrO2给出的最佳结果为:CO2转化率为20%,除甲烷以外的低碳烃的选择性接近70%。还考察了金属Fe担载量及催化剂的预还原温度对催化活性的影响,发现催化活性随金属Fe担载量的增加而呈现“双峰”现象,这种现象可能与活性物种(零价铁及配位不饱和的三价或二价铁)在催化剂表面的几何排布有关,而两种催化剂的最佳还原温度分别为723 K(5wt?/ZrO2)和773 K(5wt?/TiO2)。  相似文献   

8.
Ni基双金属催化剂加氢脱氧性能的研究   总被引:7,自引:0,他引:7  
王雪峰    王锋  陈满英  任杰 《燃料化学学报》2005,33(5):612-616
考察了Ni-M/γ-Al2O3(M=Co、Cu、Fe、La)双金属催化剂对醇、酸、酮有机含氧化合物(丁醇、丁酸、丁酮)的加氢脱氧性能,并对其中间产物进行了考察。通过TPR、XRD表征手段对Ni基催化剂的还原性能、表面分散度等特性进行了研究。结果表明,Ni基催化剂中第二活性组分相对不同有机含氧化合物表现出不同的加氢活性和选择性。对于丁酸,在Ni基催化剂中加入Fe表现出较好的活性;对于丁醇,加入La有较好的加氢脱氧性能;而对于丁酮,加入Cu更有利于提高催化剂的脱除性能。醇和酯是有机酸在Ni/γ-Al2O3催化剂上加氢转化的中间产物。  相似文献   

9.
刘思阳  白依凡  李伟 《无机化学学报》2019,35(11):2051-2056
通过加入晶种的方法降低在合成SAPO-11分子筛过程中有机胺类模板剂的含量从而减少对环境的污染。通过调节晶种及模板剂的含量,得到加入4%晶种、模板剂与Al2O3物质的量比值(ntemplate/nAl2O3)为0.6的条件下得到的晶体的形貌、结晶度等最好。分子筛负载Ni-Mo金属合成催化剂,以棕榈油加氢脱氧产物(HDO)为原料,在623 K下测得对生物航煤的选择性为66.1%,转化率为79.8%。  相似文献   

10.
综述了中国科学院大连化学物理研究所烷烃加氢异构化和加氢异构裂化反应催化剂的研发历程、工业应用及对我国石油炼制工业所做的贡献.1960年代,大连化学物理研究所在烷烃加氢异构化的研究中提出了"电子.酸性催化剂杂交规律",并相继成功研发石蜡基重油加氢异构裂化催化剂和重油单段加氢异构裂化催化剂,并应用于从大庆石蜡基原油馏分生产低冰点航空煤油.重油单段加氢异构裂化催化剂在大庆炼油厂建成的40万吨/年加氢异构裂化装置工业应用已20多年,创造了巨大的经济和社会效益.进入21世纪,大连化学物理研究所又开发出了以分子筛为载体的润滑油基础油加氢异构脱蜡催化剂,于2008年在中国石油大庆炼化公司建成20万吨/年的工业装置实现工业化应用.  相似文献   

11.
负载的Ni催化剂上植物油脂加氢脱氧制备第二代生物柴油   总被引:1,自引:0,他引:1  
在半连续反应器中,以棕榈酸甲酯为植物油脂模型化合物,进行了加氢脱氧制取高品质生物柴油燃料的研究。采用浸渍法制备了HY、SiO2、γ-Al2O3及SAPO-11四种载体负载的Ni催化剂,采用XRD、NH3-TPD、H2-TPR、BET、SEM等技术进行催化剂表征。结果表明,Ni/SAPO-11催化剂由于SAPO-11表面呈现的弱酸和中强酸性质,在保持较高的加氢脱氧反应性的同时,抑制了裂解反应的发生,具有较好的催化性能。进一步对SAPO-11上不同的Ni负载量、反应温度、反应压力等进行了研究,发现当Ni负载量为7%,反应温度为220℃,压力为2MPa时,催化剂具有较高的催化性能,棕榈酸甲酯的转化率达到了99.8%,C9~16烷烃的总选择性为92.71%。  相似文献   

12.
Ce促进Ni/SAPO-11催化剂上正庚烷的临氢异构化   总被引:1,自引:0,他引:1  
通过浸渍法制备了Ni/SAPO-11催化剂, 并进一步通过分步浸渍法制备了Ni-Ce /SAPO-11双金属催化剂, 对其晶相结构和表面酸性进行了表征. 实验结果表明, Ce的引入导致比表面积和孔容增大, 总酸量升高而酸强度降低, 金属Ni在载体SAPO-11表面的分散度提高. 通过对正庚烷的临氢异构化反应研究发现, 引入Ce可以显著提高异庚烷的选择性. 在n(H2)/n(n-C7H16)=12, MHSV=3.52 h-1, 催化剂量0.3 g, 反应温度300 ℃条件下, Ni-2%Ce/SAPO-11催化剂的正庚烷转化率可达25.4%, 异庚烷的选择性可达90.4%.  相似文献   

13.
朱数金  刘粟侥  张怀科  吕恩静  任杰 《催化学报》2014,35(10):1676-1686
以Beta分子筛为硅源通过水热合成法合成了SAPO-11/Beta复合分子筛,采用X射线衍射、N2物理吸脱附、扫描电镜、透视电镜-能谱分析、固体核磁及吡啶红外等方法对单分子筛、复合分子筛和机械混合分子筛的物化性质进行了表征.以正十二烷为模型化合物,在固定床反应器上考察了铂负载型分子筛催化剂的异构化性能.结果表明,复合分子筛的物理化学性质明显不同于单分子筛和机械混合分子筛,其呈现核壳结构,SAPO-11和Beta间存在化学作用,使得复合分子筛具有适宜的B酸分布.在正十二烷异构化反应中,复合分子筛催化剂的异构化性能优于单分子筛催化剂和机械混合分子筛催化剂,多支链异构体收率高.  相似文献   

14.
Reoxidation by carbon dioxide and reduction by methane of modified manganese and magnesium oxides have been studied. Surface oxidation has an optimum degree for reoxidation of manganese systems by carbon dioxide in contrast to that by oxygen. This leads to a higher selectivity towards C2 hydrocarbons in the reduction of manganese oxide by methane.  相似文献   

15.
Ni/KIT-6 catalysts loaded with different amounts of metallic Ni were prepared by impregnation method. The prepared catalysts and their precursors were investigated through wide- and low-angle XRD, TEM, BET, H2-TPR, and H2-TPD analyzes. The catalytic hydrodeoxygenation performance of the catalysts was evaluated using ethyl acetate as a model bio oil compound. Results indicate that the catalytic hydrodeoxygenation performance of the prepared catalysts was directly related to hydrogen storage properties, hydrogen desorption properties, dispersion of the active component Ni, and so on. The ethyl acetate conversion and ethane selectivity of 25?wt% Ni/KIT-6 catalyst were 100 and 96.8%, respectively, at 300?°C, which shows the best performance. The hydrodeoxygenation activity of ethyl acetate was higher than that of methyl acetate and isopropyl acetate because of the effect of molecular polarity and size. And, this reaction is a structure sensitive reaction.  相似文献   

16.
以Pt/SAPO-11双功能催化剂为基础,对催化剂载体进行柠檬酸、炭黑改性,以正十四烷为模型化合物,通过催化剂表征和反应评价,探索了催化剂载体的改性对正十四烷临氢转化性能的影响。结果表明,异构化产物以单甲基异构物为主,改性没有改变催化剂的酸强度,但使得酸浓度有所下降。通过柠檬酸调变催化剂的酸性使得催化剂的低温催化活性显著提高,采用炭黑扩孔改性,有效改善了催化剂的传质性能,提高了催化剂的单甲基异构体选择性。柠檬酸和炭黑改性的催化剂裂化产物均以C6为主,改性并没有改变SAPO-11分子筛的孔道限制效应,裂化产物呈现一定的择型效应,裂化产物分布呈现出不对称分布的特点。  相似文献   

17.
选用SAPO-11、ZSM-22两种分子筛为载体,浸渍Pt制备了Pt/SAPO-11和Pt/ZSM-22催化剂,以正庚烷为模型化合物,考察乙醇对催化剂临氢异构化反应性能的影响。并通过BET、XRD、C2H5OH-TPD和C2H5OH-FTIR等表征手段对催化剂的物化性能以及吸附反应性能和不同活性酸性位点进行了研究考察。结果表明,乙醇在临氢异构转化过程优先生成H2O,并以H2O的形式影响催化剂的异构化性能,催化剂异构活性与选择性随乙醇含量的增加而降低。与Pt/ZSM-22催化剂相比,Pt/SAPO-11催化剂由于有P-OH基团,表现出一定的抗含氧化物乙醇的性能。  相似文献   

18.
The concentration of trace metals in vegetable oils is an important criterion for the assessment of oil qualities with regard to freshness, keeping properties, storage and their influence on human nutrition and health. In this work, an effective and simple method for the determination of copper and lead in palm oil by stripping chronopotentiometry (SCP) is proposed. The metal ions were concentrated as their amalgams on the glassy carbon surface of a working electrode that was coated with a thin mercury film. An ultrasonic bath was used for the extraction of copper and lead from eleven oil samples using a 1:1 (v/v) mixture of concentrated hydrochloric acid and hydrogen peroxide. Efficient extraction of copper and lead (∼ 100%) was attained after 60 min of ultrasonic pre-treatment. A good correlation between the amount of sample and the time necessary for complete liberation of the metals was observed. The accuracy of the method was evaluated by means of a reference sample of skim milk powder containing trace elements (BCR 151). Quantitative analysis was carried out by the method of standard additions. Good linearity was obtained in the range of the concentrations examined. Detection limits of 13 and 50 ng g− 1 were found for Cu and Pb, respectively, in the palm oil samples. The average values found for the palm oil samples analyzed were in the range of < 0.013-2.67 µg g− 1 for copper and < 0.050-1.82 µg g− 1 for lead. The palm oil samples were also analyzed by graphite furnace atomic absorption spectrometry (GFAAS), demonstrating a very good correlation between the results.  相似文献   

19.
《Arabian Journal of Chemistry》2020,13(10):7524-7532
The present research intends to develop a new method based on headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) for the detection and determination of patin fish oil adulterated with different percentages of palm oil, because it is a cheaper vegetable oil. Five variables that affect headspace generation (incubation time and temperature, amount of sample, injection volume, and pre-heating time) have been optimized by means of a Box Behnken design in combination with Response Surface Methodology. Then, repeatability and intermediate precision have been studied where coefficients of variation lower than 10% were obtained. This new method has been applied to several samples of patin fish oil adulterated with palm oil at 20 different levels (5–50% palm oil content). The results have confirmed the suitability of the HS-GC-IMS for a rapid, easy, and reliable detection and discrimination of adulterated oil samples since a characteristic fingerprint that allows 100% successful discrimination between adulterated and unadulterated patin oil samples was achieved. Finally, a regression model has been developed to determine each sample’s adulteration level with an error lower than 10% and a coefficient of determination greater than 0.95.  相似文献   

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