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"To fulfill the requirement for synthetic fuel (synfuel) production in Fischer Tropsch process, in which syngas feed to the process has H2/CO mole ratio approaching 2, a lignite coal gasification is needed to satisfy this requirement. In this research, char particles were prepared by pyrolysis of lignite coal at controlled heating rates to obtain the highest possible surface area for gasification. The gasification used char with surface area of 172.5 m2/g, and catalyst K2CO3 in a fixed bed reactor. Steam/char mass ratio used in this research was varied 2.0; 3.0; 4.0 and the gasification temperature was varied 675, 750, 825oC. The result of this research showed that the highest H2/CO mole ratio of 2.07 corresponding to the mole ratio of gas yield/carbon of 1.13 was achieved at gasification temperature of 675oC using catalyst K2CO3 and at steam/char mass ratio of 2.0. However, at the same gasification conditions, but using no catalyst, H2/CO mole ratio and corresponding mole ratio of gas yield/carbon achieved were 3.02 and 0.42 respectively. This research found that the addition of catalyst K2CO3 in lignite coal char gasification adversely reduces mole ratio H2/CO ratio compared to that without catalysis. It is suspected that the high composition of mineral ash in ash reacts with K2CO3 catalyst which renders Boudouard reaction to considerably compete with water-gas reaction. The increases of gasification temperature and steam/carbon ratio both lower the mole ratio of H2/CO in syngas."

"Torrefaction, which is used to improve the properties of sugarcane bagasse as fuel in pulverised fuel combustion and as carbon feed in gasification, is a low heating rate pyrolysis of biomass carried out at a temperature of 200–300oC, at an atmospheric pressure, and in an inert environment. In the present work, sugarcane bagasse was torrefied at heating rates of 3, 6, and 10oC/minute, respectively, to achieve a final temperature of 275oC and after the final temperature was reached, hold times of 0 and 15 minutes, respectively occurred at a constant temperature of 275oC for a heating rate of 6oC/minute. The physical characteristics of torrefied sugarcane bagasse samples to be determined were a particle size distribution accomplished by grinding, hydrophobicity by allowing the samples to absorb moisture from the ambient air, and pellet hardness of the sample pellets. The torrefaction results show that increasing heating rate and hold time reduced the cellulose content of the sugarcane bagasse to as low as between 5.35% to 10.61% by weight composition, respectively. As the lignin content increased, the sample pellets resulted in better hardness in comparison to that measured on raw sugarcane bagasse. As the hemicellulose content increased, the samples, after grinding and stronger hydrophobicity, produced a higher fraction of smaller particle sizes. The maximum weight fraction of particles in these samples with sizes smaller than 105 µm achieved was 83.43% weight in contrast to 0.62% weight in raw sugarcane bagasse. The maximum water absorption by the samples in 3 hours was 1.28% weight in contrast to 8.02% weight by raw sugarcane bagasse. The results indicate that torrefaction is able to improve sugarcane bagasse physical characteristics, which are favourable for biomass pelletization, storage and transportation."

"Previous research of thermal co-pyrolysis of biomass-plastics where plastics function as hydrogen donor to induce synergistic effect on non-oxygenated fraction of bio-oil has reached a condition that there was a difficulty of separating non-oxygenated compounds from oxygenated compounds either at low heating rate. It was suspected that the content of high molecular weight of compounds especially polyaromatic hydrocarbons (PAH) in bio-oil retarded this separation. At low heating rate, most of co-pyrolysis until recently have been conducted in fixed bed and auger reactors. The present work proposed a stirred tank reactor as the reactor alternative to avoid formation of PAH in bio-oil. A series of experiments of co-pyrolysis of corn cobs and polypropylene at low heating rate (5oC/min) with maximum temperature of 500oC has been conducted with the ultimate goal of producing non-oxygenated fraction of bio-oil similar to diesel fuel. The qualities of the fraction targeted were its viscosity, double bond content and branching number of carbon chains. The values of these properties in diesel fuel are 2.7 cStokes, 0%, 0.4, respectively. The experiments involved 3 different reactors, i.e. the first, a stirred tank reactor with its aspect ratio (the ratio of the height to the diameter) of 2.0, the second, a stirred tank reactor with aspect ratio of 1.35 and the third, a dispecement reactor. Nitrogen gas as a sweeping gas was predicted to generate local turbulence favouring convective heat transfer. The work has resulted in some important results, i.e. the first, there was phase separation between oxygenated and non-oxygenated fractions, the second, synergistic effects in copyrolysis have been achieved both in bio-oil and non-oxygenated fraction yields, the third, non-oxygenated fraction had viscosity of 2.03 + 6.47% cStokes, the fourth, nonoxygenated fraction contained only 6-7% double bonds, which eases the hydrogenation reaction in further processing for double bond saturation, the fifth, non-oxygenated fraction had average branching number of 0.57, slightly above that of diesel fuel, which is unfavourable to reach short ignition delay time in the combustion, the sixth, the aspect ratio of the reactor significantly affected the extent of biomass pyrolysis, but not polypropylene pyrolysis."

"Deposit ampas tebu di Indonesia yang mencapai 8,5 juta ton per tahun menjadikan biomassa ini potensial untuk dikembangkan sebagai sumber energi alternatif. Perbaikan sifat ampas tebu sebagai bahan bakar padat dilakukan dengan torefaksi, yaitu proses pretreatment termokimia terhadap biomassa yang dilakukan pada suhu 200?300oC, tekanan atmosfer, dan lingkungan yang inert. Ampas tebu ditorefaksi sampai suhu 275oC dengan variasi laju pemanasan sebesar 3, 6, dan 10oC/menit dan variasi waktu penahanan suhu selama 0 dan 15 menit. Analisis yang dilakukan untuk mengetahui karakteristik fisik ampas tebu adalah kandungan lignoselulosa, distribusi ukuran partikel, sifat hidrofobik, dan kekerasan pellet. Kenaikan laju pemanasan dan waktu penahanan suhu mengurangi kandungan hemiselulosa ampas tebu sampai di bawah 6% dan menaikkan kandungan ligninnya sampai di atas 83%. Seiring peningkatan kandungan lignin, kekerasan pellet ampas tebu juga meningkat, yaitu sampai 29,22 pada skala durometer Shore D. Seiring penurunan kandungan hemiselulosa, ampas tebu bersifat lebih mudah dihancurkan dan hidrofobik. Distribusi partikel yang berukuran lebih kecil dari 105 μm pada ampas tebu yang ditorefaksi adalah sebanyak 67%, sedangkan pada ampas tebu yang tidak ditorefaksi hanya 0,62%. Penyerapan air oleh ampas tebu yang ditorefaksi hanya sebanyak 1,3%, sedangkan pada ampas tebu yang tidak ditorefaksi sampai 8,02%. Hasil ini menunjukkan bahwa torefaksi dapat memperbaiki karakteristik fisik ampas tebu.

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Sugarcane bagasse waste in Indonesia reaching 8.5 million tons per year is potential to be developed as an alternative energy source. Torrefaction, which is used to improve the properties of sugarcane bagasse as a solid fuel, is a thermochemical pretreatment of biomass carried out at a temperature of 200?300oC, atmospheric pressure, and inert environment. Sugarcane bagasse is torrefied at 275oC with the heating rate variation of 3, 6, and 10oC/minute and hold time variation of 0 and 15 minutes. Characterizations conducted to determine the physical characteristics of sugarcane bagasse are lignocellulosic content, particle size distribution, hydrophobicity, and pellet hardness. The increasing heating rate and hold time will reduce the hemicellulose content of sugarcane baggase to lower than wt-6% and increase the lignin content to higher than wt-83%. As the lignin content increases, the sugarcane bagasse pellet will have better hardness, i.e. 29.22 on a durometer Shore D scale. As the hemicellulose content increases, sugarcane bagasse will have better particle size distribution and stronger hydrophobic tendency. The particle size distribution of torrefied sugarcane bagasse which is smaller than 105 μm is wt-67% while only wt-0.62% in untorrefied sugarcane bagasse. The water absorbtion of torrefied sugarcane bagasse is wt-1.3% while wt-8.02% in untorrefied sugarcane bagasse. The results indicate that torrefaction is able to improve sugarcane bagasse

physical characteristics."

"Ko-pirolisis polipropilena dan minyak kelapa sawit memberikan cara pemanfaatan limbah plastik polipropilena. Penelitian ini akan meneliti reaksi ko-pirolisis di dalam reaktor tangki berpengaduk menggunakan katalis ceramic foam ZrO2/Al2O3-TiO2 untuk mengakomodasi ukuran molekul reaktan yang besar. Tujuan penelitian ini adalah untuk mendapatkan pengaruh laju pemanasan dan komposisi rasio umpan plastik polipropilena dari 0, 25, 50, 75, dan 100 % berat umpan terhadap hasil produk ko-pirolisis dan komposisi bio-oil. Produk dari ko-pirolisis akan dianalisis menggunakan metode Karl- Fischer, FTIR, GC-MS, C-NMR, dan DEPT 135 untuk menentukan kemungkinan jalur reaksi, komposisi senyawa, dan ikatan kimia yang ada di dalam bio-oil dan wax. Terdapat pengaruh laju pemanasan dan rasio umpan polipropilena terhadap jumlah produk dan senyawa kimia di dalam bio-oil. Penggunaan katalis ceramic foam ZrO2/Al2O3-TiO2 mampu meningkatkan kualitas dan yield produk akhir. Sistem pirolisis katalitik laju pemanasan tinggi tidak menunjukkan efek sinergis antara PP dan CPO dalam yield dan komponen non-oksigenat karena fraksi non-oksigenat yang rendah di bio-oil dan yield bio-oil yang rendah. Sistem pirolisis termal menunjukkan efek sinergis yang lebih tinggi antara PP dan CPO terhadap yield bio-oil yang lebih tinggi. Sistem pirolisis katalitik laju pemanasan rendah menunjukkan efek sinergis tertinggi antara PP dan CPO dalam hal jumlah fraksi non-oksigenat dan yield dari bio-oil. Analisis C-NMR dan DEPT-135 dari bio-oil menunjukkan bahwa sistem katalitik dan termal dengan laju pemanasan tinggi memiliki jumlah karbon yang terikat pada oksigen lebih tinggi dibandingkan dengan sistem katalitik laju pemanasan rendah yang menunjukkan efisiensi deoksigenasi yang lebih tinggi.

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Co-pyrolysis of polypropylene and crude palm oil gives the benefit of utilizing plastic waste of polypropylene. In the present research, co-pyrolysis reaction in a stirred tank reactor will be investigated using ZrO2/Al2O3-TiO2 ceramic foam catalyst to accommodate the large molecular size of reactants. The objectives are to obtain effects of heating rate and feed composition of polypropylene plastic from 0, 25, 50, 75, and 100 wt.% of total feed weight on yields of co-pyrolysis products and composition of bio-oil. The products were analyzed using Karl-Fischer, FTIR, GC-MS, C-NMR, and DEPT 135 to determine the possible reaction pathway, compound compositions, and chemical bonds in the bio-oil and wax. There is an effect of heating rate and feed composition on the yield and chemical compound of the product. The use of ZrO2/Al2O3-TiO2 ceramic foam catalyst improve the quality and yield of the final product. Catalytic high heating rate pyrolysis showed no synergetic effects between PP and CPO on bio-oil yield and non- oxygenates components due to low non-oxygenates fractions in bio-oil and low bio-oil yield. Thermal pyrolysis showed synergetic effects between PP and CPO on bio-oil yield. Catalytic low heating rate pyrolysis showed high synergetic effects between PP and CPO in terms of the quantity of non-oxygenates fractions in bio-oil and the bio-oil yield. C- NMR and DEPT-135 of bio-oil suggested that catalytic and thermal high heating rate system contained higher amount of carbon bound to oxygen compared to the catalytic low heating rate system which indicated higher deoxygenation efficiency."