scholarly journals Effect of Potassium Carbonate Catalyst on Pyrolysis of Milicia excelsa in a Fixed Bed Reactor

2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Pious O Okekunle ◽  
Oluwatobi S Awani ◽  
Daniel O Jimoh

The effect of potassium carbonate catalyst on the products distribution from pyrolysis of Milicia excelsa (Iroko) at various temperatures (400, 500 and 600 oC) was investigated. Milicia excelsa sawdust was obtained from a sawmill in Ogbomoso, South-Western Nigeria and was sundried for five days in order to reduce its moisture content. Catalytic pyrolysis of the sawdust was performed with different amounts of catalyst (10, 20, 30 and 40 wt.%). Non-catalytic pyrolysis was also performed for the same temperatures and the products distributions from both batches were compared. Char yield generally increased with increase in catalyst amount for all the temperatures considered. Tar yield did not follow any definite pattern with increasing amount of catalyst as different trends were obtained for different temperatures. Gas yield generally decreased with increase in catalyst amount in the feed. Char yields from non-catalytic experiments were higher than those obtained from catalytic runs, with the highest value of 68% at 400 oC. Tar yields from catalytic pyrolysis were higher than those from non-catalytic process at 400 oC (biomass/catalyst ratio of 90/10) and at 500 oC (biomass/catalyst ratios of 70/70 and 60/40), the highest yield being 29.47% at 500 oC and biomass/catalyst ratio of 60/40. Gas yields from catalytic pyrolysis were higher than those from non-catalytic runs except at 500 oC (biomass/catalyst ratio of 60/40), the highest being 51.3% at 600 oC (biomass/catalyst ratio of 90/10). By making use of appropriate biomass/catalyst ratio and temperature, the yield of liquid fuel from catalytic pyrolysis of Milicia excelsa can be increased.Keywords— Catalyst, potassium carbonate, pyrolysis, biomass, product distribution

2015 ◽  
Vol 659 ◽  
pp. 252-256
Author(s):  
Sudarat Chaiwatyothin ◽  
Wittawat Ratanathavorn ◽  
Tharapong Vitidsant ◽  
Prasert Reubroycharoen

Synthesis of nanoCu/ZnO catalyst for LPG production was prepared by ultrasonic spray pyrolysis (USP). Hollow spherical particles were obtained by USP technique using an aqueous solution of Cu (NO3)3.6H2O and Zn (NO3)3.3H2O with different concentration of 0.05, 0.1 and 0.5 molar under the pyrolysis temperatures of 600, 700 and 800°C. Mists of the solution were generated from the precursor solution by ultra sonic vibrators at frequency of ~1.7 MHz. The physicochemical properties of catalysts were characterized by X-ray diffraction, temperature-programmed reduction, scanning electron microscope, nitrogen adsorption-desorption, and energy dispersive X-ray spectrometer. The results showed that increasing in precursor concentration resulted in a large particle and particles size distributed in a range of 0.63-1.21 μm. Particles prepared at pyrolysis temperature 700°C exhibited homogeneous in size and shape compared to other temperature. The catalytic activity of nanoCu/ZnO-Pd-β catalysts was performed in a fixed-bed reactor for synthesizing LPG. The reaction took place at 260°C, 3.0 MPa, and the ratio of H2/CO = 2/1. All the products from the reactor were in gaseous state, and analyzed by on-line gas chromatography. The results showed that %CO conversion was high but decreased rapidly with increasing reaction time. Cu/ZnO catalyst prepared by co-precipitation gave higher %CO conversion than that prepared by ultrasonic spray pyrolysis. Moreover, hydrocarbon product distribution for Cu/ZnO catalyst produced at concentration 0.1 M 700°C by ultrasonic spray pyrolysis gave the highest LPG selectivity.


2012 ◽  
Vol 142 (11) ◽  
pp. 1382-1387 ◽  
Author(s):  
Dragomir B. Bukur ◽  
Zhendong Pan ◽  
Wenping Ma ◽  
Gary Jacobs ◽  
Burtron H. Davis

2013 ◽  
Vol 873 ◽  
pp. 562-566 ◽  
Author(s):  
Juan Liu ◽  
Xia Li ◽  
Qing Jie Guo

Chlorella samples were pyrolysed in a fixed bed reactor with γ-Al2O3 or ZSM-5 molecular sieve catalyst at 600°C. Liquid oil samples was collected from pyrolysis experiments in a condenser and characterized for water content, kinematic viscosity and heating value. In the presence of catalysts , gas yield decreased and liquid yield increased when compared with non-catalytic pyrolysis at the same temperatures. Moreover, pyrolysis oil from catalytic with γ-Al2O3 runs carries lower water content and lower viscosity and higher heating value. Comparison of two catalytic products, the results were showed that γ-Al2O3 has a higher activity than that of ZSM-5 molecular sieve. The acidity distribution in these samples has been measured by t.p.d, of ammonia, the γ-Al2O3 shows a lower acidity. The γ-Al2O3 catalyst shows promise for production of high-quality bio-oil from algae via the catalytic pyrolysis.


2015 ◽  
Vol 787 ◽  
pp. 67-71
Author(s):  
R.M. Alagu ◽  
E. Ganapathy Sundaram

Pyrolysis process in a fixed bed reactor was performed to derive pyrolytic oil from groundnut shell. Experiments were conducted with different operating parameters to establish optimum conditions with respect to maximum pyrolytic oil yield. Pyrolysis process was carried out without catalyst (thermal pyrolysis) and with catalyst (catalytic pyrolysis). The Kaolin is used as a catalyst for this study. The maximum pyrolytic oil yield (39%wt) was obtained at 450°C temperature for 1.18- 2.36 mm of particle size and heating rate of 60°C/min. The properties of pyrolytic oil obtained by thermal and catalytic pyrolysis were characterized through Fourier Transform Infrared Spectroscopy (FT-IR) and Gas Chromatography-Mass Spectrometry (GC-MS) techniques to identify the functional groups and chemical components present in the pyrolytic oil. The study found that catalytic pyrolysis produce more pyrolytic oil yield and improve the pH value, viscosity and calorific value of the pyrolytic oil as compared to thermal pyrolysis.


2017 ◽  
Vol 751 ◽  
pp. 512-517 ◽  
Author(s):  
Supranee Lao-Ubol ◽  
Phunthinee Somwongsa ◽  
Pracha Laoauyporn ◽  
Pasinee Panith ◽  
Siriporn Larpkiattaworn ◽  
...  

Five different types of silica catalyst (SBA-15, SBA-15-PO3H2, and three different Si/Al ratio of commercial zeolites (30, 80 and 280) were used to study the transformation of methanol to hydrocarbon (MTH). The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity. The mesoporous silica catalysts were prepared by co-condensation method. The catalysts samples were characterized by GC-MS, XRD, BET, and NH3-TPD techniques. The catalytic performance of synthesized and commercial catalysts for MTH process was evaluated using a homemade fixed bed reactor at temperature (300°C). It was found that the liquid hydrocarbon product provided by zeolite catalysts is aromatic hydrocarbons-rich. High Si/Al zeolites with larger pore size lead to higher selectivity and yield to paraffins (C1-C7). In contrast to commercial zeolite catalyst, SBA-15 and its modification with phosphorus species showed no conversion under studied condition. These results indicate that both pore diameter and acidity influence the product distribution in methanol to hydrocarbon process.


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