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Steam Reforming of Glycerol for Hydrogen Production over Catalyst  [PDF]
G. Sadanandam,N. Sreelatha,M. V. Phanikrishna Sharma,S. Kishta Reddy,B. Srinivas,K. Venkateswarlu,T. Krishnudu,M. Subrahmanyam,V. Durga Kumari
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/591587
Abstract: The performance of catalyst for glycerol reforming has been investigated in fixed-bed reactor using careful tailoring of the operational conditions. In this paper, a commercial Engelhard catalyst has been sized and compared to gas product distribution versus catalyst size, water-to-carbon ratio, and stability of the catalyst system. catalysts of three sizes ( , , and ?mm) are evaluated using glycerol: water mixture at to produce 2?L?H2?g?1?cat?h?1. The results indicate that ?mm size pellet is showing minimum coking and maintaining same level of conversion even after several hours of reforming activity. Whereas studies on and ?mm pellets indicate that carbon formation is affecting the reforming activity. Under accelerated aging studies, with 1?:?9 molar ratio of glycerol to water, 3?mg?carbon?g?1?cat?h?1 was generated in 20 cycles, whereas 1?:?18 feed produced only 1.5?mg?carbon?g?1?cat?h?1 during the same cycles of operation. The catalysts were characterized before and after evaluation by X-ray diffraction (XRD), BET surface area, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDAX), CHNS analysis, transmission electron microscopy (TEM), and X-ray photo electron spectroscopy (XPS). 1. Introduction The search for alternative energy sources is becoming an important aspect in the present scenario due to diminishing petroleum reserves and increased environmental pollution. Hydrogen production from biomass has great interest because of the potential application in fuel cells. Significant amount of glycerol is produced as a by-product in biodiesel production by transesterification of vegetable oils, which are available at low cost in large quantity from renewable raw materials. With increased production of biodiesel, an excess amount of glycerol (C3H8O3) is expected in the world market [1]. At present, glycerol is used in many applications including personal care, food, oral care, tobacco, polymer, and pharmaceutical applications. Besides converting glycerol into value-added chemicals [2–4], hydrogen production through reforming is alternative route [5–12]. Aqueous phase reforming of oxygenated hydrocarbons is extensively studied by the Luo et al. and Shabaker et al. [9, 13], and glycerol steam reforming is studied by Czenik et al. [14], Pompeo et al. [10], and Adhikari et al. [6, 15] over nickel-based catalysts and noble metal catalysts on different supports [16–19]. Chiodo et al. reported carbon formation of 2–6?mg?carbon?g?1?cat?h?1 by steam reforming of glycerol by Ni over MgO, CeO2, Al2O3, and Ru/Al2O3 catalysts for 20?h
Hydrogen as Carbon Gasifying Agent During Glycerol Steam Reforming over Bimetallic Co-Ni Catalyst  [PDF]
Chin Kui Cheng, Rwi Hau Lim, Anabil Ubil, Sim Yee Chin, Jolius Gimbun
Advances in Materials Physics and Chemistry (AMPC) , 2012, DOI: 10.4236/ampc.2012.24B043
Abstract: Alumina-supported bimetallic cobalt-nickel catalyst has been prepared and employed in a fixed-bed reactor for the direct production of synthesis gas from glycerol steam reforming. Physicochemical properties of the 5Co-10Ni/85Al2O3 catalyst were determined from N2-physisorption, H2-chemisorption, CO2 and NH3-temperature-programmed desorption measurements as well as X-ray diffraction analysis. Both weak and strong acid sites are present on the catalyst surface. The acidic:basic ratio is about 7. Carbon deposition was evident at 923 K; addition of H2 however has managed to reduce the carbon deposition. Significantly, this has resulted in the increment of CH4 formation rate, consistent with the increased carbon gasification and methanation. Carbon deposition was almost non-existent, particularly at 1023 K. In addition, the inclusion of hydrogen also has contributed to the decrease of CO2 and increase of CO formation rates. This was attributed to the reverse water-gas-shift reaction. Overall, both the CO2:CO and CO2:CH4 ratios decrease with the hydrogen partial pressure.
Renewable Hydrogen Produced from Different Renewable Feedstock by Aqueous-Phase Reforming Process  [PDF]
Yi Wei, Hanwu Lei, Yupeng Liu, Lu Wang, Lei Zhu, Xuesong Zhang, Gayatri Yadavalli, Birgitte Ahring, Shulin Chen
Journal of Sustainable Bioenergy Systems (JSBS) , 2014, DOI: 10.4236/jsbs.2014.42011
Abstract:

Aqueous phase reforming (APR) of biomass derived feedstock producing hydrogen was reviewed. The APR process was discussed based on different feedstock categories such as sugars, polyols and ethanol. The mechanism of APR was analyzed referring to different structures of feedstock. The reaction pathways of APR were investigated. The usage of catalysts should be judged by feedstock on the requirement including C-C bond cleavage, water-gas shift (WGS) reaction, and catalyst maintenance. The prospects were concluded based on the recent works from bimetallic catalysts and high efficient supports. Examples of significant challenges of reducing catalyst cost and increasing catalyst stability have been discussed. The modification and utilization of alkane selectivity of APR processes for liquid fuel production was also investigated.

蒙脱石负载纳米镍甘油水蒸气重整制氢
Montmorillonite supported nickel nanoparticles for hydrogen production from glycerol steam reforming
 [PDF]

张川,豆斌林,蒋博,杨明军,宋永臣
- , 2016, DOI: 10.7511/dllgxb201605003
Abstract: 采用提升pH工艺把不同含量的镍浸渍在蒙脱石(MMT)上,分别在600、700与 800 ℃ 下煅烧成型.研究Ni/MMT催化剂用于甘油水蒸气重整(GSR)制氢的效果,并通过氮气吸附、粉末X射线衍射和透射电镜对Ni/MMT催化剂进行表征.甘油水蒸气重整制氢是在 1.013× 10 5 Pa,400~600 ℃,固定床反应器中进行的.对不同镍含量以及煅烧温度对催化活性与产物选择性的影响进行分析.700 ℃煅烧的催化剂比600、800 ℃煅烧的催化剂拥有更好的催化活性.在700 ℃下煅烧的镍含量为19.89%的催化剂催化活性最好,在600 ℃时甘油转化率达到85%,同时氢气选择性为76%.实验结果表明,在400~600 ℃随着温度上升,甘油转化率上升.
Montmorillonite (MMT) supported nickel nanoparticles (Ni/MMT) with different nickel loadings are prepared by the impregnation method with rising pH technique at the calcination temperatures of 600,700 and 800 ℃ in order to investigate the performance of Ni/MMT catalysts in glycerol steam reforming (GSR) for hydrogen production. The Ni/MMT catalysts are characterized by different techniques, including nitrogen adsorption, powder X-ray diffraction and transmission electron microscope. Hydrogen production from GSR by Ni/MMT catalysts is carried out in a fixed-bed reactor under 1.013×10 5 Pa within a temperature range of 400-600 ℃. The effects of different nickel loadings on catalytic activity and product selectivity are evaluated. Compared with the Ni/MMT catalysts calcined at 600 ℃ and 800 ℃, the catalysts calcined at 700 ℃ show better catalytic activity. The catalysts calcined at 700 ℃ with nickel loading of 19.89% perform best, and the H 2 selectivity is found to be 76% and conversion of glycerol is up to 85% at 600 ℃. The experimental results show that glycerol conversion increases with increasing temperatures from 400 ℃ to 600 ℃.
NiFe/CeO2催化剂上乙二醇水相重整制氢
Hydrogen Production by Aqueous-Phase Reforming of Ethylene Glycol over NiFe/CeO2 Catalysts
 [PDF]

陈冠益,李婉晴,颜蓓蓓,单锐,姚金刚,马文超
- , 2017, DOI: 10.11784/tdxbz201601102
Abstract: 以CeO2为载体, 制备了负载型复合NiFe/CeO2催化剂, 用于乙二醇的水相重整制氢.利用N2吸附脱附(N2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H2 temperature program reduction)对催化剂的结构进行了表征, 并考察了Ni/Fe摩尔比对乙二醇水相重整制氢效果的影响以及催化剂的可重复使用性.实验结果表明:在Ni1Fe2/CeO2催化剂上的乙二醇水相重整制氢反应中, H2选择性为89.27% , 乙二醇转化率为99.13% , 烷烃选择性为11.43% ; 催化剂重复使用5次以后, 仍然保持初始活性的65% 左右.
The composite catalyst NiFe/CeO2, utilized in the hydrogen production by the aqueous-phase reforming of ethylene glycol,was prepared using CeO2 as support. The structure of the prepared catalyst was characterized by N2 adsorption-desorption,X-ray diffraction (XRD) and H2 temperature program reduction (H2-TPR),and the effect of Ni/Fe mole ratio on the hydrogen production by the aqueous-phase reforming of ethylene glycol was investigated. Additionally,the reusability of the prepared catalyst was evaluated. The experimental results showed that in the aqueous-phase reforming of ethylene glycol,on the catalyst Ni1Fe2/CeO2,the H2 selectivity,the ethylene glycol conversion and alkane selectivity was 89.27%,99.13% and 11.43% respectively. After reuse for five times,the catalytic activity of the reused catalyst was still about 65% of its original catalytic activity
Steam Reforming of Glycerol for Hydrogen Production over Catalyst  [cached]
G. Sadanandam,N. Sreelatha,M. V. Phanikrishna Sharma,S. Kishta Reddy
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/591587
Abstract:
Research of Hydrogen Production by Dimethyl Ether Reforming in Fuel Cells
Lei Guo
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104266
Abstract:
Dimethyl ether is a kind of clean fuel, which is expected to replace traditional fuel to achieve high efficiency and low emission. The research of hydrogen production by vehicle dimethyl ether reforming is imminent. This article summarizes and comments the progress of hydrogen production by dimethyl ether reforming, briefly analyzing new method of preparing catalyst. Three existing methods for hydrogen from dimethyl ether, namely steam reforming, autothermal reforming and partial oxidation reforming, are introduced. In this paper, recent researches in the field of hydrogen from dimethyl ether are reviewed.
铈镧比对CexNi0.5La0.5-xO系催化剂甘油氧化蒸汽重整制氢性能的影响
CexNi0.5La0.5-xO Catalysts for Hydrogen Production by Oxidative Steam Reforming of Glycerol: Influence of the Ce-to-La Ratio
 [PDF]

党成雄,杨浩波,余皓(),王红娟,彭峰
- , 2016, DOI: 10.3866/PKU.WHXB201603161
Abstract: 利用共沉淀法制备了CeO2和La2O3复合载体的CexNi0.5La0.5-xOO(CeNiLaO)系催化剂,在固定床反应器中考察其甘油氧化蒸汽重整制氢(OSRG)性能,并采用X射线衍射(XRD)、程序升温还原(H2-TPR)、激光拉曼光谱(Raman)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)等手段对催化剂进行表征分析。结果表明:La2O3能够有效地分散Ni颗粒,减弱Ni颗粒在反应过程中的烧结,CeO2提供的晶格氧能够消除催化剂表面的积碳,同时La会部分进入Ce的晶格取代部分Ce4+造成晶格畸变,提高表面的氧空穴数。La2O3和CeO2的共同作用有利于减弱Ni因为烧结和积碳引起的失活。在不同Ce/La摩尔比的催化剂中,Ce0.4Ni0.5La0.1O表现出最好的催化活性,并且该催化剂在长达210 h的稳定性测试中,甘油的转化率都在95%以上,气相产物中的氢气浓度达50%。
CexNi0.5La0.5-xO (CeNiLaO) catalysts were synthesized using a Ce-La composite oxide as the carrier via co-precipitation. They were applied in the oxidative steamreforming of glycerol (OSRG) in a fixed-bed reactor. The catalysts were characterized by X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Xray photoelectron spectroscopy (XPS). The results showed that La2O3 improved the dispersion of metallic Ni and suppressed the sintering of metallic Ni particles; the lattice oxygen of CeO2 inhibited and eliminated carbon deposition on the surface of the catalysts; and the substitution of some La3+ for Ce4+ ions induced a distortion of the lattice. The synergy of La2O3 and CeO2 lessened the deactivation caused by the sintering and coke deposition and improved the catalytic performance. Among the catalysts with different molar ratios of Ce to La, Ce0.4Ni0.5La0.1O had the best catalytic activity. The conversion of glycerol remained above 95% after a 210 h stability test, while a gaseous reformate of about 50% hydrogen could be steadily produced
Energetic and economic evaluation of waste glycerol cogeneration in Brazil
Albarelli, J. Q.;Santos, D. T.;Holanda, M. R.;
Brazilian Journal of Chemical Engineering , 2011, DOI: 10.1590/S0104-66322011000400014
Abstract: glycerol is an important by-product of biodiesel production. it is used in many industrial segments, but the increasing production of this chemical has become an issue of concern. many studies have been done to give new applicability to this product; a promising field is the usage of glycerol for energy production. therefore, this study evaluates the technical and economic feasibility of a new and potential proposal at the national level, the generation of electricity and heat, through a cogeneration system using glycerol. the results demonstrate the viability of this proposal, since the payback on capital invested obtained was approximately 4 years, with the possibility of reduction to 3 years when installed in regions with low infrastructure.
Thermodynamic Analysis of Ethanol Dry Reforming: Effect of Combined Parameters  [PDF]
Ganesh R. Kale,Tejas M. Gaikwad
ISRN Thermodynamics , 2014, DOI: 10.1155/2014/929676
Abstract: The prospect of ethanol dry reforming process to utilize CO2 for conversion to hydrogen, syngas, and carbon nanofilaments using abundantly available biofuel—ethanol, and widely available environmental pollutant CO2 is very enthusiastic. A thermodynamic analysis of ethanol CO2 reforming process is done using Gibbs free energy minimization methodology within the temperature range 300–900°C, 1–10 bar pressure, and CO2 to carbon (in ethanol) ratio (CCER) 1–5. The effect of individual as well as combined effect of process parameters such as temperature, pressure, and CCER was determined on the product distribution. Optimum process conditions for maximising desired products and minimizing undesired products for applications such as gas to liquids (GTL) via fischer tropsch synthesis, syngas generation for Solid oxide fuel cells, and carbon nanofilament manufacture were found in this study. 1. Introduction CO2 reforming (also known as dry reforming) is a useful way to utilize CO2 to transform it into valuable species such as hydrogen, syngas, and carbon (nanofilaments). CO2 reforming is analogous to steam reforming which has been widely used to produce hydrogen for different applications. Although dry reforming (DR) is a known process in the chemical literature, catalyst deactivation due to carbon formation was its major drawback. However, with increase in CO2 pollution awareness, researchers have started fresh studies in dry reforming to utilize (and thus sequester) CO2. This move has come with a bonus: carbon nanofilament formation was reported in some experimental studies of dry reforming. Dry reforming of natural gas was a major research area. Many research studies on dry reforming of methane have been reported [1–6]. Dry reforming of butanol [7], glycerol [8], and coke oven gas [9] has also been studied by some researchers. The popularity of biofuels and use of biomass has brought an alternative to natural gas. Ethanol is cheaply available in many countries. It is easily manufactured by biomass fermentation can be stored and transported safely. Hence, ethanol is a potential fuel that can be easily used in dry reforming processes. Dry reforming of ethanol has been studied by some researchers: De Oliveira-Vigier et al. [10] have experimentally studied the dry reforming of ethanol using a recyclable and long-lasting SS 316 catalyst and have obtained a hydrogen yield that is 98% of the theoretical value. Blanchard et al. [11] have experimentally studied the ethanol dry reforming using a carbon steel catalyst to produce syngas and nanocarbons. Bellido et al.
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