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1.
以浸渍法制备的SBA-15负载磷钼钒杂多酸(PMoV/sBA-15)为催化剂、H。Oz为氧化剂,对模拟柴油进行催化氧化脱硫,考察了H5PMo10V2040的负载量、反应温度、反应时间、氧化剂和模拟柴油体积比对脱硫效果的影响。确定最优反应条件为:H。PMo10V2040(负载量60%)/SBA-15催化剂用量0.2g、反应温度80℃、反应时间90min、氧化剂和模拟柴油体积比1:5,在此条件下,脱硫率可达98.1%。  相似文献   

2.
通过浸渍法制备固体碱催化剂:K2O-SBA-15、CaO-SBA-15和K2O/CaO-SBA-15,用于催化大豆油和无水甲醇发生酯交换反应制备生物柴油,并进行X射线衍射(XRD),氮气吸附脱附表征。结果表明,负载固体碱后,没有改变介孔分子筛SBA-15的规则孔道结构,并且碱金属氧化物均匀负载在SBA-15的孔壁上。按三组分四因素的正交试验设计方案进行实验,表明各因素影响制备生物柴油的程度依次为:反应时间反应温度醇油摩尔比催化剂用量。反应的最佳条件为:以3%K2O/3%CaO-SBA-15为催化剂,反应温度60℃,反应时间3h,醇油摩尔比为16:1,催化剂用量为油重的3%,可得生物柴油产率为87.12%。  相似文献   

3.
采用湿法浸渍法研究了五种KOH负载的催化剂催化合成生物柴油反应,并采用XRD﹑SEM﹑CO2-TPD等方法对其进行结构和性能表征。结果表明,15%(质量分数,下同)KOH负载的CaO催化酯化活性最高,在醇油摩尔比16∶1,反应温度65℃,催化剂加入量为4%条件下,反应1h,脂肪酸甲酯收率达到97.1%。KOH负载的CaO催化剂中出现了K2O的晶相,15%CaO/KOH催化剂有更多的活性位点,有利于生物柴油酯交换反应。  相似文献   

4.
采用溶胶凝胶法,以正硅酸四乙酯为硅源、乙酸钙为钙源、P123为模板剂,经一步焙烧制备了Ca/SBA-15固体碱催化剂,通过XRD、FTIR、TEM以及N2吸附-脱附等方法对催化剂的相关理化性质进行了表征,并用于催化纯化后的餐饮废油与甲醇的酯交换反应制备生物柴油。结果表明:在钙硅物质的量比为0.2、焙烧温度为700℃的条件下制备的0.2Ca/SBA-15-700固体碱催化剂具有最佳的催化效果;0.2Ca/SBA-15-700固体碱催化剂能够很好保持SBA-15原有的二维六方相有序介孔结构,BET比表面积为406.7m2·g-1;在醇油物质的量比为12、催化剂用量为5%、氮气气氛中65℃反应7h制得的生物柴油产率达到94.7%;催化剂经洗涤和干燥,无需活化可继续使用,连续使用5次后,催化活性有所下降,但生物柴油产率仍保持在86%以上。  相似文献   

5.
采用浸渍法将两种金属酞菁-α-八丁氧基酞菁钴(CoPc)和α-八丁氧基酞菁铜(CuPc)负载到介孔分子筛SBA-15上,制备CoPc/SBA-15和CuPc/SBA-15两种催化剂,通过紫外-可见光谱、红外光谱、N2吸附对其结构进行表征,研究pH值、催化剂类型、催化剂用量、底物浓度以及反应温度对催化效果的影响。实验结果表明:在相同的催化条件下,两种催化剂对巯基乙醇(ME)均表现出良好的催化性能,且CuPc/SBA-15的催化氧化性能优于CoPc/SBA-15,符合酶催化氧化反应的特征,遵循米氏方程动力学规律,其米氏常数和最大反应速率分别为27.23 mmol/L和1.72×10-4 L/min,该催化反应属于吸热反应,其活化能Ea为29.17 kJ/mol。  相似文献   

6.
以四水硫酸锆改性HY-SBA-15(ZS/HVSBA-15)为催化剂,催化大豆油和甲醇制备生物柴油,考察最佳制备条件。实验结果表明,四水硫酸锆负载量为30%,n(甲醇):n(大豆油)-12:1,m(催化剂):m(大豆油)=3%,m(溶剂):m(大豆油):30%,120℃下反应6h,生物柴油的收率可达96.78%。对合成出的生物柴油性能指标进行检测,结果表明其主要性能指标与我国0^#柴油相接近。  相似文献   

7.
制备了介孔磷钨杂多酸催化剂HPWA/SBA-15,用XRD、FTIR和BET等方法进行表征,并用于催化大豆油酯交换反应制备生物柴油。结果表明,介孔磷钨杂多酸催化剂具有较好的催化性能,其催化性能与介孔杂多酸催化剂优良的扩散性能和均一的质子酸特性有关,在活性组分负载质量分数为35%、反应温度190℃、反应时间7 h、n(醇)∶n(油)为16∶1和催化剂用量为大豆油质量的5%条件下,生物柴油收率可达97%。  相似文献   

8.
以自制的SBA-15为载体,磷钨酸为活性组分,用过量浸渍法制备了HPW/SBA-15催化剂,并采用SEM、BET和TG-DTA对催化剂进行表征分析。H2O2为氧化剂,十六烷基三甲基溴化铵(CTAB)为相转移剂,以二苯并噻吩(DBT)的模型化合物(DBT为溶质、正辛烷为溶剂)进行氧化脱除为探针反应,考察了磷钨酸负载量和HPW/SBA-15的焙烧温度对催化剂活性的影响,同时考察了氧化-萃取工艺条件对真实柴油脱硫效果的影响。实验结果表明,磷钨酸最佳负载量为30%,HPW/SBA-15在250℃焙烧处理时活性最高;在n(H2O2):n(S)=6、HPW/SBA-15用量为2.5%(基于柴油质量)、CTAB用量为0.4%(基于柴油质量)、萃取级数为4、温度60℃反应1.5h的条件下,柴油硫含量从1317mg/L降到39mg/L,脱硫率达到97.0%、收率不低于85.0%。气相色谱结果显示,该催化氧化脱硫体系容易脱除柴油中加氢难以脱除的二苯并噻吩及其衍生物。  相似文献   

9.
简述了餐饮废油( WCO)转化为生物柴油的反应原理,比较了利用WCO转化制备生物柴油的各种方法,主要有均相转化法(包括酸催化法、碱催化法和酸碱两步催化法)、非均相转化法(包括固体碱催化法、固体酸催化法)、酶催化法、超临界转化法等,分析了不同方法的特点。  相似文献   

10.
通过溶胶凝胶法制备了SBA-15,采用浸渍法制备了固体碱催化剂La_2O_3-CaO/SBA-15,通过XRD进行了表征,将所制备的催化剂用于酯交换反应。探讨了镧钙物质的量比、焙烧温度、反应时间和催化剂用量对于生物柴油产率的影响。结果表明,当催化剂的焙烧温度为800℃,镧钙物质的量之比为0.5,反应时间为3h,催化剂质量为大豆油质量的3%时,生物柴油的产率为90.11%。  相似文献   

11.
SBA-15的改性及催化文冠果油制备生物柴油   总被引:1,自引:0,他引:1  
柳杨  衣怀峰  陈宇  吴玉龙  陈曾  杨明德  童军茂 《化工进展》2011,30(6):1247-1252,1258
以介孔分子筛SBA-15为载体,采用直接合成法和后合成法镀饰Al后再负载碱金属盐KNO3,制得负载型固体碱催化剂KNO3-AlSBA-15和KNO3-Al-SBA-15。用XRD、BET、SEM以及CO2-TPD对催化剂进行表征。结果表明:在SBA-15上镀饰Al可以保护分子筛的介孔结构;进一步负载KNO3,能够增强催化剂的碱性。将其应用于催化文冠果油酯交换制备生物柴油,结果显示催化剂KNO3-Al-SBA-15的催化活性最好,优于传统均相催化剂,所得生物柴油产率可达92%,重复使用多次仍具有较好的催化效果。  相似文献   

12.
K/SBA 15 was investigated for the transesterification of palm oil. The influence of temperature, reactants' ratio, catalyst loading and reaction time on the biodiesel yield was studied using a Central Composite Design (CCD). The process optimization using Response Surface Methodology (RSM) was performed and the interactions between the operational variables were elucidated. The optimum conditions were found to be 70 °C for the reaction temperature, 11.6 mol/mol for methanol to oil ratio, 3.91 wt.% for the catalyst loading and 5 h for the reaction time to achieve 93% of biodiesel yield. High catalytic activity was attributed to high surface area of the catalyst and the relatively easy diffusion of reactants in the mesopores. The effect of catalyst loading and reaction time was relatively more dominant in affecting the biodiesel yield. High potential of SBA-15 as catalyst for biodiesel production was demonstrated.  相似文献   

13.
A heterogeneous chiral catalyst Fe(III)-CS (chitosan) complex/mesoporous molecular sieve SBA-15 (Santa Barbara Amorphous) was prepared. The asymmetric transfer hydrogenations of prochiral acetophenone and 4-methyl-2-pentanone to corresponding chiral alcohols were carried out on Fe-CS/SBA-15 at atmosphere pressure using 2-propanol as hydrogen donor. Effects of Fe content in catalyst, reaction temperature, reaction time and promoter KOH concentration on the conversion of substrates and enantio-selectivity were investigated. Fe-CS/SBA-15 with 2.2% mass fraction Fe exhibits considerable enantioselectivity and catalytic activity for the asymmetric transfer hydrogenations of aromatic ketone and aliphatic ketone. Under optimal reaction conditions: KOH concentration 0.03 mol/L, reaction temperature 70°C and reaction time 4 h, enantiomer excess (ee) of (R)-1-phenylethanol and conversion of acetophenone can reach 87.4% and 27.7%, respectively. Under the above KOH concentration and reaction temperature and reaction time of 8 h, the ee of (R)-4-methyl-2-pentanol and conversion 4-methyl-2-pentanone amounted to 50.2% and 25.5%, respectively. Translated from Petrochemical Technology, 2006, 35(9): 858–862 [译自: 石油化工]  相似文献   

14.
CeNi/SBA-15 and LaNi/SBA-15 catalysts were prepared by deposition–precipitation (DP) method and characterized by N2 physical adsorption, XRD, H2-TPR, H2-chemisorption and TEM. Their catalytic performances in the ammonia decomposition reaction were tested and compared with Ni/SBA-15 catalyst. Addition of cerium and lanthanum oxides to the Ni/SBA-15 catalyst caused some decrease of BET surface area and pore volume of the catalysts, but led to a promotion effect to their catalytic activity which was closely related to the ratio of Ce (La)/Ni. The highest conversion of ammonia could be obtained when the Ce (La)/Ni ratio was around 0.3. The promotion effect is more evident on CeNi/SBA-15(0.3) than on LaNi/SBA-15(0.3) catalyst under identical reaction conditions. The CeNi/SBA-15 and LaNi/SBA-15 catalysts show smaller nickel particle size and easier reducibility in comparison with the Ni/SBA-15 catalysts.  相似文献   

15.
Catalytic combustion of benzene over metal oxides supported on SBA-15   总被引:1,自引:0,他引:1  
The catalytic combustion of benzene over metal oxides supported on SBA-15 was investigated. The catalysts were prepared by the incipient wetness method and characterized by XRD, BET, TEM, ESR and TPR. The calcined siliceous SBA-15 and CuO/SBA-15 samples displayed well-resolved patterns with a sharp peak at about 1.0°. It is clear that the loading of CuO on the silica matrix drastically decreases the surface area and pore volume of the catalysts, as would be expected for the incorporation of CuO. Among the supported metal oxides, CuO supported on SBA-15 was found to have the highest activity for benzene oxidation. In addition, copper oxide supported on SBA-15 gives higher catalytic activity than copper oxide supported on MCM-41. From the ESR results, the CuO dispersed on the SBA-15 acts as the active site of the CuO/SBA-15 catalysts in the oxidative decomposition of benzene. The catalytic activity gradually increases with increasing CuO loading on SBA-15.  相似文献   

16.
薛君  申力涛 《工业催化》2013,21(8):31-36
以介孔分子筛SBA-15为载体,采用浸渍法制备M/SBA-15(M=Cu、Fe、Cr) 介孔分子筛催化剂。采用XRD、BET、FT-IR、H2-TPR和XPS等对样品进行分析表征,在固定床微型反应器中评价M/SBA-15(M=Cu、Fe、Cr)分子筛催化剂催化NO+CO的反应性能。结果表明,负载金属的SBA-15分子筛仍保持高度有序的二维六方介孔结构,比表面积和孔径略有减少,负载的活性金属组分在SBA-15分子筛表面具有较高的分散度。Cu/SBA-15、Cr/SBA-15和Fe/SBA-15催化剂对NO+CO反应体系均有一定活性,但由于活性金属自身的特性及其在载体表面负载量的差异,3种催化剂上呈现的NO还原活性不同,顺序为:Cr/SBA-15>Cu/SBA-15>Fe/SBA-15。  相似文献   

17.
The heterogeneous base catalyst, γ-Al2O3 loaded with KOH and K (K/KOH/γ-Al2O3) was first prepared and used in the transesterification of rapeseed oil with methanol to produce biodiesel. The prepared catalyst was characterized by X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller method, infrared spectroscopy and X-ray photoelectron spectroscopy. It was found that when γ-Al2O3 is loaded with KOH and K, the Al–O–K species is produced, resulting in an increase in the catalytic activity. The impacts of catalyst preparation conditions on the catalytic activities of K/KOH/γ-Al2O3 were investigated. The results demonstrate that the catalyst K/KOH/γ-Al2O3 has high catalytic activity when the added amounts of KOH and K are 20 and 7.5 wt% respectively. The transesterification of rapeseed oil to biodiesel with the prepared heterogeneous base catalyst was optimized. It was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 60°C, with a 9:1 molar ratio of methanol to oil, a catalyst amount of 4 wt%, and a stirring rate of 270 g.  相似文献   

18.
以介孔分子筛SBA-15为载体,制备一系列不同La含量的La-Ni2P/SBA-15催化剂前驱体,将La-Ni2P/SBA-15前驱体涂覆在预处理的整体式载体堇青石上,在H2气氛程序升温还原,制备不同La含量的La-Ni2P/SBA-15/堇青石整体式催化剂。对合成的催化剂进行X射线衍射和N2吸附-脱附结构表征,并评价对二苯并噻吩的加氢脱硫活性。结果表明,Ni2P存在于所有的La-Ni2P/SBA-15/堇青石整体式催化剂中,且随着La含量的增加,La-Ni2P/SBA-15/堇青石整体式催化剂的比表面积和孔体积均有一定程度的提高,催化活性也提高。对于Ni2P/SBA-15/堇青石整体式催化剂,在300 ℃和380 ℃时,二苯并噻吩加氢脱硫转化率仅为27.2%和91.3%;而1.5%La-Ni2P/SBA-15/堇青石催化剂在300 ℃和380 ℃时,二苯并噻吩转化率分别为36.8%和96.3%,显示出较好的二苯并噻吩加氢脱硫活性。La-Ni2P/SBA-15/堇青石整体式催化剂在对二苯并噻吩的加氢脱硫过程中,以直接脱硫和加氢脱硫两种脱硫方式同时进行,并且以直接脱硫为主。  相似文献   

19.
The feasibility of the production of biodiesel from trap grease containing 51.5% free fatty acids (FFAs) was investigated. The esterification of FFAs by an acid catalyst followed by the transesterification of triglycerides by an alkali catalyst was examined. The esterification of trap grease by sulfuric acid as a homogeneous catalyst or by Amberlyst-15 as a heterogeneous catalyst was optimized through a response surface methodology. After the two-step esterification of trap grease by sulfuric acid, the acid value decreased from 102.9 mg KOH/g to 2.75 mg KOH/g. Through the transesterification by potassium hydroxide, fatty acid methyl ester (FAME) content reached 92.4%. Following the esterification of trap grease by Amberlyst-15, the acid value decreased to 3.23 mg KOH/g. With the transesterification by potassium hydroxide, FAME content increased to 94.1%. After the distillation of the produced biodiesel, FAME content increased again, to 97.6%. The oxidation stability of the trap grease biodiesel was 0.17 h, and its cold filter plugging point was 4 °C. As the FAME content of the trap grease biodiesel satisfies the Korean Biodiesel Standard, the trap grease biodiesel seems to be applicable for use as an engine fuel after properties improvement.  相似文献   

20.
Pt-supported on mesoporous SBA-15 catalysts (Pt/SBA-15) have been investigated for selective catalytic reduction of NO by propene in excess oxygen. Catalytic activity of Pt/SBA-15 can be improved by the post-synthesis modification of Al into SBA-15. The resulting material (AlSBA-15) retains a hexagonal order and physical properties of the parent SBA-15 and shows new acid sites. Increased acid sites are confirmed by NH3-TPD. Medium acid site appeared at 200 °C and broad strong acid site appeared above 250 °C. A certain degree of support acidity of Pt/AlSBA-15 increased the NO conversion, but when there are too many acid sites, carbon deposition becomes extensive and lead to decrease the NO conversion. The influence of different Pt loadings on the catalytic properties was also investigated.  相似文献   

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