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"Sebagai upaya memenuhi kebutuhan bahan bakar penerbangan yang meningkat, sintesis bioavtur dari bahan biomassa lignoselulosa bisa menjadi solusi saat ini. Bonggol jagung sebagai bahan baku dipilih karena kelimpahannya di Indonesia mencapai 7,2 juta ton/tahun dan kandungan holoselulosa yang tinggi sehingga akan menguntungkan saat dikonversi menjadi bio-oil dengan pirolisis. Tujuan penelitian ini untuk mendapatkan analisis kandungan bio-oil dan mendapatkan analisis literatur potensi senyawa yang dominan pada langkah peningkatan mutu bio-oil dan katalisnya dari penelitian eksperimental. Pirolisis ditempuh dengan laju pemanasan rendah sebesar 50C/menit hingga temperatur 5000C dengan kecepatan pengaduk 100 rpm. Berdasarkan analisis GC-MS, komposisi senyawa terbanyak pada bio-oil berupa asam benzoat sebesar 44,45%, yang terbentuk dari oksidasi aldehid yang didahului oleh oksidasi alkohol. Ditinjau dari analisis NMR, ikatan kimia dominan yang terdeteksi ialah membentuk siklopentenon, dengan ikatan C pada siklopentena dan karbonil keton yang masing-masing sebesar 55,61% dan 34,81% pada C-NMR, serta ikatan H pada siklopentena dan C-alfa di keton dengan kelimpahan 47,41% dan 25,19% pada H-NMR. Pembentukan siklopentenon memperlihatkan ciri khas proses slow pyrolysis dengan menghadirkan lebih banyak reaksi siklisasi yang terjadi dari hasil dehidrasi cincin glukosa yang terbuka. Bio-oil dengan dominan siklopentenon ini merupakan basis awal untuk pembentukan bioavtur dengan densitas dan nilai kalor yang tinggi seperti bi(siklopentana). Berdasarkan tinjauan pustaka, rute mekanisme reaksi upgrading dengan katalis dapat dilakukan melalui urutan proses hidrogenasi dengan katalis Cu-Ni-Al dengan yield siklopentanon 95,8%, kondensasi aldol siklopentanon dengan katalis MgO-ZrO2 mampu mencapai yield 2-siklopentilidin-siklopentanon sebesar 84,6%, dan hidrodeoksigenasi disertai katalis Ni/SiO2 menghasilkan bi(siklopentana) dengan yield sebesar 93%. Katalis untuk reaksi hidrogenasi dan hidrodeoksigenasi harus bersifat asam dan untuk reaksi kondensasi aldol bersifat asam-basa. Sebagai produk bioavtur potensial berupa bi(siklopentana) dengan rasio H/C sebesar 1,8 dinilai telah mendekati bioavtur komersial dengan rasio H/C 1,92. Kuantifikasi biomassa yang terkonversi menjadi bioavtur potensial berupa bi(siklopentana) melalui mekanisme senilai 15,96%.

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To fulfill the need of aviation fuel, the synthesis of bioavtur from lignocellulosic biomass can be the current solution. Corn cobs as raw material was chosen because of its potential abundance in Indonesia reaching 7.2 million tons/year and high holocellulose content so that it will be more profitable when converted to bio-oil by pyrolysis. The purpose of this study is to obtain the the bio-oil compositions analysis and obtain a literature analysis of the potential of dominant compounds in the step of improving the quality of bio-oil and its catalysts from experimental research. Pyrolysis is pursued at a low heating rate of 50C/min to a temperature of 5000C with a stirring speed of 100 rpm. Based on GC-MS analysis, the composition of most compounds in bio-oil is benzoic acid with 44.45%, which is formed from oxidation of aldehydes preceded by oxidation of alcohol. In terms of the NMR analysis, the dominant chemical bonds detected were to form cyclopentenone, with C bonds on cyclopentene and carbonyl ketones which were 55.61% and 34.81% on C-NMR, and H bonds on cyclopentene and C-alpha to ketones with an abundance of 47.41% and 25.19% in H-NMR, respectively.The formation of cyclopentenone shows the special characteristics of slow pyrolysis process by presenting more cyclization reactions that occured from the dehydration results of an opened-glucose ring. Bio-oil with cyclopentenone dominant composition is the initial basis for bioavtur synthesize with high density and high heating value characteristics such as bi(cyclopentane). Based on literature review, the mechanism of upgrading reactions with catalysts can be carried out through a sequence of hydrogenation processes with a Cu-Ni-Al catalyst with a cyclopentanone yield of 95.8%, aldol condensation of cyclopentanone with MgO-ZrO2 catalyst was able to reach a yield of 2-cyclopentylidine-cyclopentanone for 84, 6%, and hydrodeoxygenation with Ni/SiO2 catalyst produced bi(cyclopentane) with a yield of 93%. The catalyst for the hydrogenation and hydrodeoxygenation reactions must be acidic and for the aldol condensation reaction is acidic-base. As a potential bioavtur product in the form of bi(cyclopentane) with an H/C ratio of 1.8, it is considered to have approached a commercial bioavtur with an H/C ratio of 1.92. Quantification of biomass converted into bi(cyclopentane) as bioavtur potential was 15.96%."

"ABSTRAK

Penelitian torrefaksi bonggol jagung telah dilakukan untuk mempelajari pengaruh laju alir nitrogen terhadap yield dan komposisi bonggol jagung yang dihasilkan melalui proses torrefaksi. Pengaruh laju alir nitrogen diteliti dengan memvariasikan laju alir nitrogen sebesar 0,3 L/min, 0,5 L/min, dan 0,7 L/min dengan masing-masing variasi laju alir nitrogen dilakukan pada 3 variasi suhu torrefaksi, yaitu 250oC, 275oC, dan 300oC. Proses torrefaksi berlangsung di reaktor tubular dengan holding time 20 menit, heating rate 10oC/menit, dan total massa umpan 15 gram. Identifikasi pengaruh laju alir nitrogen dilakukan dengan menganalisis bonggol jagung hasil torrefaksi dengan menggunakan karakterisasi FTIR, Ultimate, dan Thermogravimetri Analysis (TGA). Hasil penelitian ini menunjukkan bahwa terdapat pengaruh laju alir nitrogen terhadap yield dan komposisi bonggol jagung hasil torrefaksi. Semakin besar laju alir nitrogen maka yield dari bonggol jagung hasil torrefaksi akan semakin kecil. Semakin besar laju alir nitrogen, kandungan oksigen dalam bonggol jagung hasil torrefaksi akan semakin berkurang dan kandungan karbonnya meningkat. Kandungan oksigen setelah torrefaksi menurun hingga 38% pada saat suhu torrefaksi 300oC dengan laju alir nitrogen sebesar 0,7 L/min sementara kandungan karbonnya meningkat hingga 44% bila dibandingkan dengan bonggol jagung umpan torrefaksi, rasio C/O meningkat dari 0,95 menjadi 2,19 dan rasio C/H meningkat dari 6,9 menjadi 13,99. Berdasarkan karakterisasi FTIR seiring semakin besar laju alir nitrogen maka gugus fungsi fenol, guaiacol, catechol, dan ether akan semakin tinggi. Data karakterisasi TGA menunjukan bahwa laju alir nitrogen tidak berpengaruh terhadap suhu pirolisis dari bonggol jagung yang sudah ditorrefaksi. Suhu torrefaksi adalah faktor yang mempengaruhi dari suhu pirolisis bonggol jagung yang sudah ditorrefaksi.

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ABSTRACT

Torrefaction of corn cobs has been carried out to study the effect of nitrogen flow rate on yield and torrefied corn cobs composition produced through torrefaction. The effect of nitrogen flow rate was investigated by varying the nitrogen flow rate by 0,3 L/min, 0,5 L/min, and 0,7 L/min with each nitrogen flow rate variation performed on 3 torrefaction temperature variations are 250oC, 275oC, and 300oC. Torrefaction process takes place in a tubular reactor with a holding time of 20 minutes, a heating rate of 10oC/ minute, and a total feed mass of 15 grams. Identification of the effect of nitrogen flow rate was carried out by analyzing the torrefaction corn cobs using FTIR, Ultimate, and Thermogravimetric Analysis (TGA) characterizations. The results of this study indicate that nitrogen flow rate affects yield and torrefied corncobs composition. The greater the nitrogen flow rate, the lower is the yield of torrefied corn cobs. The greater the flow rate of nitrogen, the lower is the oxygen content in the corn cobs and the higher is the carbon content. The oxygen content after torrefaction decreased up to 38% when the torrefaction temperature was carried out at 300oC with a nitrogen flow rate of 0.7 L/min while the carbon content increased by 44%, the C/O ratio increased from 0,95 to 2,19 and the C/H ratio increased from 6,9 to 13,99. Based on FTIR characterization, increasing nitrogen flow rate increases the functional groups furan, phenol, guaiacol, catechol, and ether. Based on the TGA characterization, the nitrogen flow rate did not affect the pyrolysis temperature of the torrefied corn cobs. Torrefaction temperature is a factor that influences the pyrolysis temperature of torrefied corn cobs."

"Fast pyrolysis biomassa dapat menghasilkan bio-oil dengan potensi aplikasi yang luas, salah satunya dapat digunakan sebagai bio-fuel. Sayangnya, bio-oil berbasis biomassa memiliki sifat fisikokimia yang buruk dan banyak mengandung senyawa oksigenat sehingga heating value-nya rendah. Plastik diketahui memiliki rasio H/C yang lebih tinggi dan miskin akan oksigen sehingga slow co-pyrolysis biomassa dengan plastik dapat digunakan sebagai solusi upgrading bio-oil yang sederhana, efektif dan murah. Dengan mencampurkan keduanya, sebuah efek sinergetik akan tercipta untuk memperbaiki kuantitas dan kualitas bio-oil yang dihasilkan. Bonggol jagung dipilih sebagai biomassa karena kandungan total selulosanya yang tinggi dan ketersediaannya yang melimpah di Indonesia. Bonggol jagung akan dipirolisis bersama-sama dengan plastik polipropilena dalam reaktor batch berpengaduk dengan variasi rasio plastik dalam umpan sebesar 12,5%, 25%, 37,5%, 50%, 62,5%, 75%, dan 87,5%. Kondisi operasi dengan suhu maksimum sebesar 500oC, laju alir N2 sebesar 0,5 L/menit, holding time 10 menit dan heating rate 5oC/menit digunakan selama eksperimen berlangsung. Terjadi peningkatan pH, densitas, dan warna pada bio-oil hasil slow co-pyrolysis. Karakterisasi GC-MS menunjukkan penurunan senyawa oksigenat di dalam bio-oil berbanding lurus dengan komposisi plastik dalam umpan. Efek sinergetik teramati saat rasio plastik ≥50%. Komposisi umpan 12,5% bonggol jagung dan 87,5% plastik PP menghasilkan yield tertinggi dengan kandungan senyawa oksigenat terendah.

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Fast pyrolysis of biomass produces bio-oil with many potential applications, one of them is to be bio-fuel. Unfortunately, biomass derived bio-oil has low physicochemical properties and contains lot of oxygenated compounds thus the heating value is low. Plastics are known to have higher H/C ratio and almost no oxygen content, so co-pyrolysis of biomass and plastic could be used as a simple, effective yet cheap bio-oil upgrading solution. By mixing those two as a feed, a synergetic effect will occur and improve the bio-oil both in quantity and quality.

Corn cobs are chosen as the biomass due to its high cellulose content and availability. Corn cobs will be slow co-pyrolyzed with polypropylene plastic in a two stirrer batch reactor with plastic ratio variation of 12,5%, 25%, 37,5%, 50%, 62,5%, 75%, and 87,5%. Maximum temperature of 500oC, 0,5 L/min nitrogen flow, 10 minutes holding time and heating rate of 5oC/min was used in the experiment. pH, density, and color improvement were observed.

GC-MS results showed that lower oxygenated compounds in the bio-oil are associated with higher plastic feed composition. Synergetic effect is happened when plastic ratio is ≥50%. Composition of 12,5% corn cobs and 87,5% polypropylene plastic is found to produce the highest yield of bio-oil with the lowest oxygenates."

"Bonggol jagung merupakan limbah dengan jumlah yang cukup banyak di Indonesia. Sejauh ini pemanfaatan utama untuk biomassa. Namun biomassa tersebut masih mengalami kendala karena tingginya senyawa oksigenat yang menyebabkan heating value-nya rendah. Plastik polipropilena diketahui memiliki rasio H/C yang lebih tinggi dan miskin akan oksigen sehingga slow co-pyrolysis biomassa dengan plastik dapat digunakan sebagai solusi upgrading bio-oil yang sederhana, efektif dan murah. Pencampuran biomassa dan plastik akan menghasilkan efek sinergetik dalam memperbaiki kuantitas dan kualitas bio-oil yang dihasilkan. Berbagai penelitian pada slow co-pyrolysis telah dilakukan terutama pada reaktor tubular dengan rasio tinggi terhadap diameter, lebih dari 4. Tetapi untuk skala besar, bentuk reaktor seperti ini sangat sulit dilakukan scale-up. Pada penelitian ini reaktor dibuat dengan rasio kurang dari 2. Perpindahan panas khususnya pada plastik yang memiliki konduktivitas termal rendah dibantu dengan adanya pengaduk untuk memperbaiki persebaran perpindahan panas tersebut. Identifikasi pengaruh efek sinergetik dilakukan dengan menganalisis bio-oil menggunakan FTIR dan GC-MS. Efek sinergetik yield bio-oil terjadi pada komposisi PP terhadap bonggol jagung sebesar 50-87,5 dengan 87,5 sebagai yield tertinggi. Sementara efek sinergetik kualitas bio-oil yang berupa peningkatan senyawa non-oksigenat terjadi pada komposisi PP 37,5-87,5.

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Corn cob is a waste which has considerable amount in Indonesia. So far, its utilization especially for biomass. However, biomass still having problems because the high oxygenate compound which causes low heating value. The pure polypropylene plastic has a H C ratio higher and poor in oxygen, so slow co pyrolysis of biomass with plastic can be used for bio oil upgrading solutions which is simple, effective and inexpensive. By mixing the two feedstocks, a synergetic effect would be created to improve the quantity and quality of the bio oil produced. Various studies on the slow co pyrolysis has been carried out mainly in the tubular reactor with a high ratio of the diameter, more than 4. But for large scale, that reactor design will be very difficult to scale up.

This research, reactor was made with a ratio less than 2. The heat transfer especially on the plastic that has a low thermal conductivity helped by stirrer to improve the distribution of heat transfer. Identification of the synergetic effect was done by analyzing bio oil using FTIR and GC MS. Synergetic effects of bio oil yield occurred in the composition of the PP towards corn cobs of 50 to 87.5 which 87.5 as the highest yield. While the synergetic effect of the quality in bio oil as an increase in the composition of the non oxygenate which exist in PP composition 37.5 to 87.5."

"Penelitian slow co-pyrolysis bonggol jagung dan plastik polipropilena telah dilakukan untuk mempelajari pengaruh laju alir gas pembawa terhadap yield dan komposisi bio-oil yang dihasilkan. Pengaruh laju alir gas pembawa diteliti dengan memvariasikan laju alir nitrogen sebesar 400 mL/menit, 500 mL/menit, dan 600 mL/menit dengan masing-masing variasi laju alir nitrogen dilakukan pada 3 rasio komposisi bonggol jagung dan plastik polipropilena, yaitu 0 :100 , 50 :50 , dan 100 :0 . Proses slow co-pyrolysis berlangsung di reaktor tangki berpengaduk, dengan suhu akhir 500°C, holding time 10 menit, heating rate 5oC/menit, dan total massa umpan 100 gram. Identifikasi pengaruh laju alir gas pembawa dilakukan dengan menganalisis bio-oil fasa polar dan nonpolar menggunakan FTIR, GC-MS, dan H-NMR. Hasil penelitian ini menunjukkan terdapat pengaruh laju alir gas pembawa terhadap yield dan komposisi bio-oil hasil slow co-pyrolysis bonggol jagung dan plastik polipropilena. Semakin besar laju alir nitrogen menghasilkan yield bio-oil yang semakin besar dan yield char yang semakin rendah. Yield bio-oil tertinggi sebesar 47,9 mL pada laju alir nitrogen 600 mL/menit, sedangkan efek sinergetik terbaik sebesar 35 pada laju alir nitrogen 400 mL/menit. Berdasarkan karakterisasi GC-MS dan H-NMR seiring semakin besar laju alir nitrogen maka gugus fungsi alkana semakin rendah dan alkena semakin tinggi pada bio-oil nonpolar, serta gugus fungsi karboksilat semakin rendah dan gugus fungsi furan, fenol, guaiacol, catechol semakin tinggi pada bio-oil polar.

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Research that focused on slow co pyrolysis of corn cobs and polypropylene plastic has been done to study the effect of carrier gas flow rate on yield and composition of bio oil. The effect of carrier gas flow rate was investigated by varying nitrogen flow rate of 400 mL min, 500 mL min and 600 mL min with each variation performed on 3 ratio of corn cobs and polypropylene plastic are 0 100 , 50 50 , and 100 0 . The slow co pyrolysis process takes place in a stirred tank reactor, with final temperature of 500°C, holding time of 10 minutes, heating rate of 5oC min, and total mass of feed 100 grams. Identification of the effect of carrier gas flow rate is done by analyzing polar and nonpolar phase bio oil using FTIR, GC MS, and H NMR.

The results of this study indicate that there is an effect of carrier gas flow rate on yield and bio oil composition of slow co pyrolysis of corn cobs and polypropylene plastic. The greater the nitrogen flow rate results in greater bio oil yield and lower yield char. The highest bio oil yield was 47.9 mL at nitrogen flow rate of 600 mL min, while the best synergetic effect was 35 at nitrogen flow rate of 400 mL min. Based on the characterization of GC MS and H NMR as the greater the nitrogen flow rate the alkane functional group is lower and the higher the alkene in nonpolar bio oil, and the lower carboxylic functional groups and the furan, fenol, guaiacol, catechol functional groups are higher in polar bio oil. "

"Minyak kelapa sawit memiliki potensi yang tinggi untuk dikembangkan menjadi bio-oil oleh karena kandungan trigliserida. Indonesia merupakan negara produsen kelapa sawit terbesar di dunia. Selama ini minyak kelapa sawit belum dimanfaatkan secara maksimal khususnya sebagai bahan baku industri. Padahal minyak kelapa sawit dapat dimanfaatkan sebagai energi terbarukan melalui proses slow co-pyrolysis. Dalam penelitian ini, trigliserida yang digunakan dari minyak goreng kelapa sawit. Selain itu, limbah plastik juga berlimpah di Indonesia, terutama plastik polipropilena. Tujuan penelitian ini adalah untuk mengetahui pengaruh laju oenambahan plastik polipropilena terhadap yield dan kualitas bio-oil hasil slow co-pyrolysis minyak kelapa sawit. Penelitian ini dilakukan dalam reactor tabung berpengaduk pada suhu 550oC, heating rate 5oC/menit, kecepatan pengaduk 65 RPM dengan laju alir gas nitrogen 550 mL/min. Variasi yang dilakukan berupa penambahan jumlah % massa plastik polipropilena yang akan mempengaruhi yield dan komposisi dari bio-oil yang dihasilkan. Bio-oil dikarakterisasi dengan menggunakan GC-MS, dan FTIR. Efek sinergetik pada pirolisis PP-trigliserida tidak terjadi, sedangkan pada pirolisis PP-bonggol jagung terjadi saat komposisi PP 50% dan 75%. Bio-oil optimum dihasilkan pada komposisi PP 75% baik pada pirolisis PP-trigliserida dan PP-bonggol jagung.

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Palm oil has high potential to be developed into bio-oil because of the content of triglycerides. Indonesia is the largest palm oil producer in the world. So far, palm oil has not been fully utilized, especially as an industrial raw material. Even though palm oil can be used as renewable energy through the slow co-pyrolysis process. In this study, the the triglyceride is from palm oil cooking oil. In addition, plastic waste is also abundant in Indonesia, especially polypropylene plastic. The purpose of this study was to determine the effect of the rate of addition of polypropylene plastic on the yield and quality of bio-oil produced by slow co-pyrolysis of palm oil. This research was conducted in a stirred tube reactor at a temperature of 550oC, heating rate of 5oC / minute, stirrer speed of 65 RPM with a nitrogen gas flow rate of 550 mL / min. The variation is in the form of increasing the mass% of polypropylene plastic which will affect the yield and composition of the bio-oil produced. Bio-oil is characterized by using GC-MS, and FTIR. The synergetic effect on PP-triglyceride pyrolysis did not occur, whereas in the pyrolysis of PP-corn hump occurred when the composition of PP was 50% and 75%. Optimum Bio-oil was produced in the composition of PP 75% both in PP-triglyceride pyrolysis and PP-corncobs.

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"Bonggol jagung memiliki potensi yang tinggi untuk dikembangkan menjadi bio-oil oleh karena banyaknya limbah pertanian jagung Indonesia. Selain itu, limbah plastik juga berlimpah di Indonesia, terutama plastik polipropilena. Co-pyrolysis antara bonggol jagung-plastik polipropilena memiliki efek sinergetik yang mengubah sebagian fraksi polar dari bio-oil menjadi fraksi non-polar yang mengandung senyawa non-oksigenat sebagai bahan baku untuk sintesis biofuel. Pada percobaan ini, pirolisis dari fraksi non-polar dilakukan untuk memproduksi bio-oil yang memiliki karakteristik yang dekat dengan bensin. Pirolisis dilakukan pada dua tahapan, di mana tahap pertama adalah co-pyrolysis untuk memproduksi fraksi non-polar dan tahap kedua adalah untuk mempirolisis fraksi non-polar tersebut untuk menurunkan viskositasnya menjadi dekat dengan viskositas bensin. Kedua tahap pirolisis akan dilakukan dalam reaktor tabung berpengaduk pada suhu 100 RPM, heating rate 5°C/menit, dan laju alir nitrogen 750 mL/menit pada tekanan gas nitrogen 3 bar. Variasi yang dilakukan berupa suhu akhir pirolisis tahap kedua. Produk bio-oil dikarakterisasi menggunakan H-NMR, GC-MS, LC-MS, FTIR, dan viskometer. Yield dan viskositas bio-oil dari hasil pirolisis tahap kedua bergantung kepada suhu akhir pirolisis, di mana semakin tinggi suhu, yield akan semakin tinggi dan viskositas juga cenderung untuk semakin tinggi. Adapun bio-oil dengan suhu akhir pirolisis tahap kedua 300°C memiliki karakteristik yang paling dekat dengan bensin.

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Corncobs biomass has a high potential to be developed into bio oil because of large amount of maize farm waste in Indonesia. In addition, plastic waste is also abundant in Indonesia, especially polypropylene. Co pyrolysis between corncobs and polypropylene has a synergetic effect that transforms some polar fraction of bio oil into non polar fraction containing non oxygenate compounds as precursor for synthesis of biofuel. In the present work, pyrolysis of the non polar fraction of bio oil was led to produce bio oil which had similar characteristics to that of gasoline. The pyrolysis was carried out in two stages, where the first stage was co pyrolysis to produce non polar bio oil and the second stage was pyrolysis of non polar fraction to reduce its viscosity similar to that of gasoline. The first and second stage pyrolysis was carried out in a stirred tank reactor at 100 RPM, heating rate of 5°C min and nitrogen flow rate of 750 mL min under 3 bar nitrogen gas pressure with the second stage pyrolysis final temperature varied. The resulting bio oil product was characterized by FT IR, GC MS, H NMR, viscometer and LC MS. Bio oil viscosity and yield of the second stage pyrolysis heavily depended on its final temperature, in which the higher the temperature, the higher was the viscosity, yet the higher was the bio oil yield. Bio oil with secondary pyrolysis final temperature of 300°C has the most similarities to gasoline characteristics. "

"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."

"ABSTRAKPada penggunaan stirred tank reaktor dengan rasio Length/Diameter yang rendah, terjadi beberapa masalah dalam transfer panas, karena itu, fasa polar pada hasil pirolisis masih memiliki panjang rantai karbon yang panjang. Dengan mengubah cara feeding dari twice feeding, menjadi gradual feeding, diharapkan dapat meningkatkan jumlah fasa polar pada panjang rantai karbon rendah. Bonggol jagung dipilih sebagai biomassa karena kandungan total selulosanya yang tinggi dan ketersediaannya yang melimpah di Indonesia. Polipropilena adalah jenis plastik yang cukup banyak dihasilkan di Indonesia dan selain itu memiliki ratio Hydrogen/Carbon yang tinggi. Dengan mencampurkan keduanya, sebuah efek sinergetik akan tercipta untuk memperbaiki kuantitas dan kualitas bio-oil yang dihasilkan. Kondisi operasi dengan suhu maksimum sebesar 500oC, laju alir N2 sebesar 0,75 L/menit, holding time 10 menit dan heating rate 5oC/menit digunakan selama eksperimen berlangsung. Dari eksperimen ini terlihat bahwa proses slow co pyrolysis memiliki 2 regime yang dapat terlihat dari jumlah peningkatan yield bio-oil dan peningkatan signifikan pada volume polar. Hasil FTIR dan GC-MS menunjukan adanya fasa polar yang dominan oleh karboksilat dan fenol, pada fasa polar dominan oleh alkena. Untuk digunakan sebagai bio-fuel, bio-oil memiliki nilai TAN total acid number yang rendah pada fasa polar, dan viskositas yang mendekati dengan bahan bakar komersial.

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ABSTRACTIn the use of stirred tank reactors with low Length Diameter ratios, there are some problems in heat transfer, therefore, the polar phase on the pyrolysis results still has long carbon chain length. By changing the way feeding of the two step feeds, to gradual feeding, is expected to increase the number of polar phases at low carbon chain lengths. Corncobs are selected as biomass because of their high total cellulose content and abundant availability in Indonesia. Polypropylene is a type of plastic that is widely produced in Indonesia and other than it has a high Hydrogen Carbon ratio. By mixing the two, a synergetic effect will be created to improve the quantity and quality of the resulting bio oil. Operating conditions with a maximum temperature of 500oC, N2 flow rate of 0.75 L min, holding time of 10 min and a heating rate of 5oC min were used during the experiment. From this experiment we can see that the slow co pyrolysis process has 2 regimes that can be seen from the increasing amount of bio oil yield and the significant increase in polar volume. FTIR and GC MS results show the dominant polar phase by carboxylic and phenol, in the polar phase dominant by alkene. For use as bio fuel, bio oil has a low TAN value total acid number in polar phase, and viscosity is close to commercial fuel."

"Untuk meningkatkan bio-oil baik dari segi kualitas dan kuantitas, co-pyrolysis jerami padi dengan plastik HDPE dan PP, yang mengandung kadar hidrogen tinggi, dapat menjadi salah satu solusi. Prosedur slow co-pyrolysis dilakukan pada reaktor batch dengan laju pemanasan 5℃ /menit hingga suhu 500℃ dan laju aliran nitrogen yang digunakan adalah 750 mL/menit. Produk cair selanjutnya dianalisis dengan menggunakan GC-MS. Hasil penelitian menunjukkan bahwa semakin besar rasio berat plastik/biomassa menghasilkan yield char yang rendah serta yield oil dan yield gas yang cenderung meningkat dengan hasil bio-oil maksimum diperoleh melalui co-pyrolysis PP/jerami padi dengan rasio berat 25:75, yakni 12,88%. Besarnya rasio berat plastik/biomassa juga mempengaruhi penurunan senyawa aldehid dan fenol pada kandungan bio-oil. Adapun lama waktu penahanan menunjukkan adanya reaksi cross-linking sehingga meningkatkan yield waxy solid.

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To improve the quality and quantity of bio-oil derived from rice straw pyrolysis, the idea of incorporating plastics (HDPE and PP) containing higher hydrogen contents can be considered. Slow co-pyrolysis performed in a batch reactor with a heating rate of 5℃ /min up to a temperature of 500℃ with nitrogen flow rate 750mL/min. Liquid products were than analyzed by GC/MS.

The results showed that the greater the weight ratio of plastic/biomass produces low char yield with oil and gas yield are likely to increase. The maximum yield of bio-oil obtained (12,88%) through co-pyrolysis of PP/rice straw with a weight ratio of 25;75. Upon increasing weight ratio of plastic/biomass, the decline of aldehyde and phenol compunds in bio-oil were observed. The increasing holding time thus further promotes cross-linking reaction thereby increasing the amount of waxy solid obtained."