scholarly journals Pengembangan katalis Ni/Al2o3 untuk steam reforming tar hasil gasifikasi

2018 ◽  
Vol 10 (2) ◽  
pp. 43
Author(s):  
Deviana Pramitasari ◽  
S Subagjo
Keyword(s):  
Nickel Catalyst ◽  
Steam Reforming ◽  
Coke Formation ◽  
Fixed Bed ◽  
Xrd Analysis ◽  
Phase Changes ◽  
Fixed Bed Reactor ◽  
Deactivation Of Catalyst ◽  
Toluene Conversion ◽  
Tar Cracking

The development of catalysts Ni/Al2O3 for steam reforming gasification tar This research studied the secondary tar removal in gasification technology through catalytic toluene steam reforming reactions. The objective of this study was to obtain a nickel catalyst that has good performance for steam reforming of tar (toluene) by selecting the -Al2O3 or -Al2O3 supports, and adding promoter to inhibit deactivation due to coke formation. The performance of the catalyst is determined from the activity test in a fixed bed reactor at a temperature of 700 oC, atmospheric pressure, Time on Stream (TOS) 10 hours and stability test indicated by XRD and TGA. The catalyst showed the best performance was the Ni/-Al2O3 catalyst with the average of toluene conversion of 96%. The addition of 2% and 5% by weight of CaO decreased the catalytic activity. Although it proved to inhibit the formation of coke, it did not reduce the rate of deactivation of catalyst. The XRD analysis showed that the Ni/-Al2O3 after 10 hours in operation did not undergo any phase changes, thus the catalyst was still stable. Keywords: tar cracking, steam reforming, nickel catalyst, toluene conversion, stability. AbstrakPenelitian ini merupakan suatu bagian dalam pengembangan teknologi penghilangan tar gasifikasi secara sekunder dengan cara perengkahan katalitik menggunakan reaksi steam reforming toluen. Tujuan penelitian ini adalah mendapatkan katalis berbasis nikel yang memiliki kinerja yang baik untuk steam reforming tar (toluen) dengan memilih penyangga -Al2O3 atau -Al2O3, dan menambah promotor CaO untuk menghambat deaktivasi akibat pembentukan arang. Kinerja katalis ditentukan dari uji aktivitas di dalam reaktor fixed bed pada temperatur 700 oC, tekanan atmosferik, selama 10 jam dan uji stabilitas yang diindikasikan menggunakan XRD dan TGA. Hasil pengujian aktivitas memperlihatkan bahwa katalis Ni/-Al2O3 menghasilkan aktivitas yang paling baik dengan rata - rata konversi toluen 96%. Penambahan promotor CaO 2% dan 5% berat menurunkan aktivitas katalis Ni/-Al2O3 dan menghambat pembentukan arang, tetapi tidak mengurangi laju deaktivasi katalis. Hasil XRD katalis Ni/-Al2O3 setelah reaksi 10 jam menunjukkan tidak adanya perubahan fasa dari -Al2O3 ke -Al2O3, yang berarti katalis masih tetap stabil.Kata Kunci: perengkahan tar, katalis nikel, konversi toluen, stabilitas.

scholarly journals Ni-based catalysts for steam reforming of tar model derived from biomass gasification

2019 ◽  
Vol 90 ◽  
pp. 01015 ◽  
Author(s):  
Ru Shien Tan ◽  
Afizah Alir ◽  
Saiful Azam Mohamad ◽  
Khairuddin Md Isa ◽  
Tuan Amran Tuan Abdullah
Keyword(s):  
Catalytic Activity ◽  
Steam Reforming ◽  
Coke Formation ◽  
Fixed Bed ◽  
Biomass Gasification ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Variable Pressure ◽  
Major Barrier ◽  
Filamentous Carbon

Tar formation during biomass gasification is a major barrier to utilise the produced syngas, which clogs processing equipment. In the present study, steam reforming of gasification-derived tar (phenol, toluene, naphthalene, and pyrene) was catalysed by Ni/dolomite, Ni/dolomite/Al2O3, Ni/dolomite/La2O3, Ni/dolomite/CeO2, and Ni/dolomite/ZrO2 for hydrogen production. The steam reforming experiment was conducted in a fixed bed reactor at 700 °C and the steam-to-carbon molar ratio of 1 under atmospheric pressure. After the catalytic test, the spent catalysts were characterised by thermogravimetric analysis and variable-pressure scanning electron microscope. The aim of this study is to investigate the catalytic activity of Ni-based catalysts in terms of tar conversion and their deactivation characteristic. The current results revealed that all the catalysts showed almost full conversion of tar (98.8%-99.9%) and considerably low amount of coke deposited in the form of amorphous and filamentous carbon (15.9-178.5 mg gcat-1). Among the catalysts studied, Ni/dolomite/La2O3 gave the highest catalytic activity for steam reforming of gasified biomass tar and lowest coke formation.

Hydrogen Production from Ethanol Steam Reforming: Fixed Bed Reactor Design

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Pablo Giunta ◽  
Norma Amadeo ◽  
Miguel Laborde
Keyword(s):  
Steam Reforming ◽  
Flow Model ◽  
Multicomponent Mixture ◽  
Plug Flow ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Ethanol Steam Reforming ◽  
Heterogeneous Model ◽  
Ethanol Steam ◽  
Hydrogen Stream

The aim of this work is to design an ethanol steam reformer to produce a hydrogen stream capable of feeding a 60 kW PEM fuel cell applying the plug flow model, considering the presence of the catalyst bed (heterogeneous model). The Dusty-Gas Model is employed for the catalyst, since it better predicts the fluxes of a multicomponent mixture. Moreover, this model has shown to be computationally more robust than the Fickian Model. A power law-type kinetics was used. Results showed that it is possible to carry out the ethanol steam reforming in a compact device (1.66 x 10 -5 to 5.27 x 10 -5 m3). It was also observed that this process is determined by heat transfer.

scholarly journals Analysis and Model-Based Description of the Total Process of Periodic Deactivation and Regeneration of a VOx Catalyst for Selective Dehydrogenation of Propane

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1374
Author(s):  
Andreas Brune ◽  
Andreas Seidel-Morgenstern ◽  
Christof Hamel
Keyword(s):  
Catalyst Deactivation ◽  
Process Development ◽  
Coke Formation ◽  
Fixed Bed ◽  
Reaction Network ◽  
Fixed Bed Reactor ◽  
Side Reactions ◽  
Model Based ◽  
Total Process

This study intends to provide insights into various aspects related to the reaction kinetics of the VOx catalyzed propane dehydrogenation including main and side reactions and, in particular, catalyst deactivation and regeneration, which can be hardly found in combination in current literature. To kinetically describe the complex reaction network, a reduced model was fitted to lab scale experiments performed in a fixed bed reactor. Additionally, thermogravimetric analysis (TGA) was applied to investigate the coking behavior of the catalyst under defined conditions considering propane and propene as precursors for coke formation. Propene was identified to be the main coke precursor, which agrees with results of experiments using a segmented fixed bed reactor (FBR). A mechanistic multilayer-monolayer coke growth model was developed to mathematically describe the catalyst coking. Samples from long-term deactivation experiments in an FBR were used for regeneration experiments with oxygen to gasify the coke deposits in a TGA. A power law approach was able to describe the regeneration behavior well. Finally, the results of periodic experiments consisting of several deactivation and regeneration cycles verified the long-term stability of the catalyst and confirmed the validity of the derived and parametrized kinetic models for deactivation and regeneration, which will allow model-based process development and optimization.

scholarly journals Cu-Ni Nanocatalysts in Mesoporous MCM-41 and TiO2 to Produce Hydrogen for Fuel Cells via Steam Reforming Reactions

2015 ◽  
Vol 1096 ◽  
pp. 161-168 ◽  
Author(s):  
Richard Yeboah Abrokwah ◽  
Vishwanath G. Deshmane ◽  
Sri Lanka Owen ◽  
Debasish Kuila
Keyword(s):  
Surface Area ◽  
Steam Reforming ◽  
Anatase Phase ◽  
High Surface ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Reaction Products ◽  
One Pot ◽  
Steam Reforming Of Methanol ◽  
Mcm 41

We have synthesized mesoporous SiO2(MCM-41) and TiO2encapsulated bimetallic Cu-Ni nanocatalysts using an optimized one-pot hydrothermal procedure. The catalysts were characterized using BET, XRD, TGA-DSC and HRTEM techniques. While bimetallic Cu-Ni/MCM-41catalysts have high surface area- 634-1000 m2/g, Cu-Ni/TiO2yields surface area of 250-350 m2/g depending on the metal loading (5-10 wt%). The XRD studies confirmed a long range ordered structure in Cu-Ni/MCM-41 and the presence of the catalytically active anatase phase in the crystalline Cu-Ni/TiO2. The results from HRTEM studies were consistent with the mesoporosity of both supports. These catalysts were tested for methanol conversion and H2/CO selectivity via steam reforming of methanol (SRM) reactions in a fixed bed reactor. There is a distinct difference in the performance of these two supports. Bimetallic 3.33%Cu6.67%Ni/TiO2catalyst showed an impressive 99% H2selectivity at as low as 150°C and a maximum conversion of 92% at 250 °C but 3.33%Cu6.67%Ni/MCM-41 catalyst did not show any H2selectivity at 150°C and only ~12% conversion at 250°C. The effect of each support and relative metal loadings on the activity and selectivity of the SRM reaction products at different temperatures is discussed.

Hydrogen production from chemical looping steam reforming of glycerol by Ni based Al-MCM-41 oxygen carriers in a fixed-bed reactor

Fuel ◽  
2016 ◽  
Vol 183 ◽  
pp. 170-176 ◽  
Author(s):  
Bo Jiang ◽  
Binlin Dou ◽  
Kaiqiang Wang ◽  
Yongchen Song ◽  
Haisheng Chen ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Chemical Looping ◽  
Oxygen Carriers ◽  
Mcm 41

Hydrogen Production from Ethanol Steam Reforming over Ni-Cu/ZnO Catalyst

2011 ◽  
Vol 236-238 ◽  
pp. 1067-1072
Author(s):  
Li Ping Liu ◽  
Xiao Jian Ma ◽  
Peng Zhang ◽  
Ya Nan Liu
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Surface Characteristics ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Ethanol Steam Reforming ◽  
Hydrogen Yield ◽  
Ethanol Steam

Hydrogen production by ethanol steam reforming over Ni-Cu/ZnO catalyst in the temperatures range of 250-550°C was studied on a fixed bed reactor. The effects of reaction temperature and water/ethanol molar ratio on hydrogen production were investigated. The structure and surface characteristics of the catalyst were measured by scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential thermal analyzer (TG-DSC). The results show that the Ni-Cu/ZnO catalyst has good catalytic performance with higher hydrogen yield of 4.87molH2/molEtOH reacted. A comparison of hydrogen production from ethanol steam reforming over Ni-Cu/ZnO catalyst with over a commercial catalyst was made in this paper.

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