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"Pada 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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In 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."

"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. "

"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."

"Bio-oil produced by biomass pyrolysis contains high oxygenates, namely, carboxylic acids, alcohols, and ketones resulting in low calorific fuel, and therefore bio-oil requires upgrading to sequester these oxygenates. By conducting the co-pyrolysis of biomass and plastic feed blend, the donation of hydrogen by plastic free radicals to the oxygen of biomass free radicals may sufficiently reduce oxygenate compounds in the bio-oil and increase its yield. Therefore, the synergetic effects are functional. Currently, co-pyrolysis reactors have high aspect ratios (ratio of height to diameter) of 4 or more and small diameters (maximum 40 mm), in which the heat transfer from the furnace to the feed blend is immaterial even though the plastic material has low thermal conductivity. However, in large-scale reactors, such a design restricts the bio-oil’s capacity due to the heat transfer constraint. To resolve the latter and to improve bio-oil quality, in the present work, the co-pyrolysis of corn cobs and polypropylene (PP) is conducted in a stirred-tank reactor with a low aspect ratio (2). PP composition in the feed blend was varied from 0-100% weight with a 12.5% weight interval, heating rate of 5oC/min, and final temperature of 500oC. The results show that by increasing the PP composition in the feed blend from 37.5% to 87.5%, the bio-oil yield increased from 25.8% to 67.2% feed weight. An analysis of bio-oil quality shows that there was a favorably abrupt increase of non-oxygenate composition in the bio-oil from less than 5% to more than 70% as the PP composition in the feed blend was increased from 37.5% to 50% and more."

"Bonggol jagung dan plastik polipropilena merupakan sampah yang berlimpah di Indonesia, namun belum didaur ulang dengan maksimal. Bio-oil hasil proses co-pyrolysis biomassa dan plastik dapat dimanfaatkan menjadi salah satu sumber alternatif bio-fuel. Plastik polipropilena, yang memiliki rasio H/C yang tinggi dapat menjadi sumber hidrogen yang baik bagi bio-oil pirolisis biomassa. Dengan melakukan co-pyrolysis pada kedua bahan ini, sebuah efek sinergetik akan terjadi sehingga bio-oil yang dihasilkan akan memiliki kuantitas dan kualitas yang lebih baik. Peningkatan kualitas bio-oil ditandai dengan berkurangnya kadar oksigen akibat pengusiran H. Reaksi berlangsung pada reaktor tangki berpengaduk, dengan kondisi operasi 500oC, laju alir N2 750 mL/menit, holding time 10 menit dan heating rate 5oC/menit. Yield bio-oil non-polar mengalami kenaikan seiring dengan bertambahnya komposisi PP pada umpan. Wax mengalami kenaikan jumlah ikatan jenuh seiring dengan kenaikan komposisi PP akibat terjadinya transfer hidrogen pada proses pirolisis. Proses pirolisis dapat menyebabkan degradasi termal yang menyebabkan produk pirolosis mempunyai berat molekul yang lebih rendah.

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Corncob and polypropylene plastics are abundant waste in Indonesia which have not been fully recycled to its fully potential. Co pyrolysis of corncob and plastic can be one of alternative source of bio fuel. Polypropylene plastic, which is high in H C ratio can be a good hydrogen source for pyrolysis oil from biomasss. Co pyrolysing biomass and plastic could lead to synergetic effect which yields higher quantitiy of liquid product. Low oxygenated compound in bio oil is caused by hydrogen resulting in higher quality of bio oil. The reaction occurs in a stirred tank reactor, with operation condition 500oC, N2 flowrate 750 mL min, holding time 10 minutes and heating rate 5oC min. Non oxygenated bio oil yield is significantly increase as polypropylene composition in feed increased. Wax shows raised amount of double bonds as PP composition increase due to hydrogen transfer in pyrolysis. Pyrolysis can cause thermal degradation which leads to lower molecular weight of the products."

"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."

"Parameter COD dan TDS merupakan dua parameter yang nilainya paling tinggi pada limbah susu yaitu dengan kisaran 1.000-8.000 mg/L untuk COD dan 1.000-4.000 mg/L untuk TDS. Penelitian ini dilakukan untuk menurunkan kedua nilai parameter tersebut menggunakan bioreaktor Microbial Fuel Cell (MFC) yaitu merupakan sebuah teknologi alternatif pengolahan limbah yang dapat mendegradasi kandungan organik limbah serta menghasilkan energi listrik secara langsung tanpa membutuhkan konversi dan untuk melihat potensi limbah susu secara teoritis dalam menghasilkan energi listrik Penelitian dilakukan selama 2 bulan dengan membuat reaktor. MFC skala laboratorium dengan jenis single chamber tanpa membran berukuran 16/L dengan dimensi 40/20/20 cm Terdapat penambahan bakteri Escherichia coli untuk meningkatkan degradasi kandungan organik limbah. Penelitian yang dilakukan secara batch ini menunjukkan efisiensi penurunan COD sebesar 51 pada waktu tinggal 13 hari sedangkan TDS mengalami peningkatan karena adanya penambahan larutan elektrolit. Dengan konsentrasi COD influen sebesar 3.853 mg/L penurunan rata rata COD dari total yang tersisihkan adalah 7.7 setiap harinya Limbah susu ini memiliki potensi untuk dijadikan substrat dalam reaktor MFC karena secara teoritis dapat menghasilkan arus maksimum sebesar 340 mA dengan efisiensi Coulomb sebesar 13 Hasil ini lebih besar dibandingkan dengan penelitian lain yang menggunakan limbah domestik sebagai substrat.

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COD and TDS are two parameters that have the highest value in dairy wastewater with a COD ranging between 1.000 and 8.000 mg/L and a TDS ranging between 1.000 and 4.000 mg/L. The aim of this study is to reduce the value of these parameters by using a Microbial Fuel Cell (MFC) bioreactor an alternative wastewater treatment technology that can degrade the organic content of the wastewater and produce electrical energy directly without the need of conversion and to see theoretically the dairy wastewater potential in power generation Research is done for 2 months by creating a laboratory scale MFC reactor with single chamber type without a membrane and has reactor volume of 16/L with dimensions of 40/20/20 cm. There is an addition of Escherichia coli bacteria to increase the degradation of the organic content of the wastewater Research which carried out in batch shows COD removal efficiency of 51 at the HRT of 13 days while TDS has increased due to the addition of an electrolyte solution As influent COD concentration is 3.853 mg/L the average decrease of the total excluded COD was 7.7 per day Therefore dairy wastewater has the potential to be used as a substrate in MFC reactor because theoretically it can produce a maximum current of 340 mA with Coulomb efficiency of 13. These result is greater than other research that use domestic wastewater as a substrate."

"Microbial Fuel Cell (MFC) merupakan sebuah perangkat elektrokimia yang memanfaatkan mikroorganisme untuk menghasilkan listrik dari hasil metabolisme dalam memecah senyawa oraganik. Limbah cair industri tempe berpotensi untuk dijadikan sebagai substrat MFC. Limbah cair industri tempe masih mengandung nutrisi yang tinggi untuk mikroba. Penelitian ini difokuskan pada sisi aspek pengolahan limbah ditentukan dari penurunan kadar COD dan BOD. Variasi dalam penelitian ini adalah variasi jenis larutan elektrolit, konsentrasi penambahan mediator, waktu pembentukan biofilm, dan penambahan bakteri gram selektif. Kinerja elektrolit yang paling bagus adalah Kalium Persulfat dibandingkan Natrium Klorida dengan penurunan COD dan BOD sebesar 23,07% dan 37,02%. Penambahan mediator dengan konsentrasi 20 g/L menghasilkan penurunan kadar COD dan BOD sebesar 25,92% dan 37,44%. Variasi berikutnya tidak menggunakan mediator ekstrak ragi karena meningkatkan kadar awal limbah secara signifikan. Waktu pembentukan biofilm optimum adalah 7 hari yang menghasilkan penurunan kadar COD dan BOD sebesar 18,2% dan 35,9%.Penambahan bakteri gram negatif sebanyak 5 mL menurunkan kadar COD dan BOD sebesar 29,32% dan 51,32%. Penelitian lebih lanjut dibutuhkan untuk menghasilkan penurunan kadar limbah yang lebih besar supaya dapat memenuhi baku mutu limbah.

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Microbial Fuel Cell (MFC) is an electrochemical device that uses microorganisms to produce electricity from the metabolism in the breakdown of organic compounds. Industrial wastewater of tempeh is potential to be a MFC substrate. Tempe industrial wastewater contains high nutrient for microbes. This study focused on the aspects of waste treatment which is determined by decreased levels of COD and BOD. Variations in this study are electrolyte solutions, the concentration of yeast extract addition as mediator, the formation time of biofilm, and the addition of selective gram. Potassium Persulphate result better performance than Sodium Chloride with COD and BOD removal amounted to 23.07% and 37.02%. The addition of a mediator with a concentration of 20 g/L decrease COD and BOD levels by 25.92% and 37.44%. The next variation will not use yeast extract mediator because it enhances the initial level of wastes significantly. Biofilm formation optimum time is 7 days which decrease COD and BOD levels by 18.2% and 35.9%. The addition of gram negative bacteria decrease COD and BOD levels by 29,32% dan 51,32%. Further research is needed in order to get a better result on decreasing levels of COD and BOD."

"Penelitian yang sudah dilakukan sebelumnya menunjukkan bahwa ada 2 regime reaksi co-pyrolysis yang memiliki perbedaan trend pada yield bio-oil-nya, yaitu regime dengan komposisi plastik dalam umpan reaktor kurang dari 40 regime 1 dan regime dengan komposisi plastik dalam umpan reaktor lebih dari 40 regime 2 .Penelitian yang dilakukan saat ini berhasil membuktikan bahwa hal tersebut merupakan pengaruh perpindahan panas bahan dalam reaktor. Perpindahan panas dipelajari dengan melihat suhu yang direkam oleh termokopel pada tujuh lokasi yang berbeda di dasar reaktor. Hasil yang didapatkan adalah pada regime 1, perpindahan panas terjadi dengan dominasi oleh radiasi ke biomassa, sedangkan pada regime 2 didominasi oleh konveksi ke plastik. Variasi komposisi pada regime 1 tidak berpengaruh kepada perubahan suhu dalam campuran sedangkan pada regime 2 menunjukkan semakin kecil komposisi biomassa maka semakin tinggi suhu campuran yang dicapai. Penelitian ini menunjukkan bahwa perpindahan panas belum terjadi dengan merata pada campuran sehingga pirolisis biomassa belum dapat mencapai pirolisis sekunder dengan baik sedangkan pirolisis plastik sudah menghasilkan distribusi produk yang merata.

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The previous research shows that there are two regimes of co pyrolysis reaction which have different trend of bio oil rsquo s yield, they are the regime with plastic composition in reactor feed less than 40 regime 1 and regime with plastic composition in reactor feed more than 40 regime 2 .Current research has proved that it is the effect of heat transfer of materials in the reactor. The heat transfer was studied by looking at the temperature recorded by the thermocouple at seven different locations at the bottom of the reactor. The result is that in regime 1, heat transfer occurs dominanty by radiation to biomass, whereas in regime 2 it is dominated by convection to plastic.The variation of composition in regime 1 does not affect the temperature change in the mixture, while in regime 2 the smaller the composition of the biomass the higher the mixed temperature is achieved. This study shows that heat transfer has not occurred evenly on the mixture so that biomass pyrolysis has not been able to achieve the secondary pyrolysis well whereas plastic pyrolysis has produced an even distribution of the product."

"ABSTRAKMaterial plastik, seperti polipropilena PP , yang mengandung banyak hidrogen sangat potensial untuk digunakan sebagai sumber hidrogen pada co-pyrolysis bersama biomassa seperti bonggol jagung. Dengan mencampurkan keduanya, akan tercipta suatu efek sinergetik yang akan meningkatkan kualitas bio-oil yang dihasilkan. Investigasi yang mengarah pada fenomena efek sinergetik ini dievaluasi dengan menggunakan reaktor displacement untuk melakukan proses slow co-pyrolysis. Eksperimen yang melibatkan umpan yang didominasi biomassa, yaitu PP < 50 regime 1 , terjadi kontraksi pada reaktor kemudian diikuti dengan tidak berubahnya displacement dari silinder piston, sementara pada pirolisis umpan yang didominasi plastik, yaitu PP ge; 50 regime 2 menunjukkan adanya swelling dan contraction pada reaktor. Pada regime 1, sifat termoplastis tidak muncul pada char, sementara pada regime 2, sifat termoplastis muncul pada char. Eksperimen juga menunjukkan bahwa pada komposisi PP < 37,5 , char masih mengandung senyawa oksigenat, dan pada PP ge; 37,5 , char tidak mengandung oksigen. Sementara itu, pada komposisi PP 75 menunjukkan adanya perpindahan massa oksigen hasil pirolisis biomassa ke lelehan plastik. Hasil semua eksperimen di atas menunjukkan bahwa pirolisis umpan regime 2 mengindikasikan adanya interaksi yang kuat antara hasil pirolisis biomassa dan plastik PP yang mengarah ke efek sinergetik

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ABSTRACTPlastic material, such as polypropylene plastic PP , which has hydrogen content compared to that in biomass, is potential to be used as a hydrogen source for pyrolysis of biomass, such as corncobs. By mixing these two, certain synergistic effect will appear that will improve the quality and quantity of bio oil produced. Investigation of the phenomenon leading to the synergistic effect has been evaluated by using a displacement reactor in the form a tubular batch reactor to perform slow co pyrolysis. Feed compostion was varied at 12.5 , 25 , 37,5 , 50 , 62,5 , 75 , and 87.5 weight of PP . Experiment involving biomass dominated feeds, i.e. PP 50 regime 1 , reactor contracted followed by no displacement of reactor piston, while plastic dominated feeds, i.e. PP ge 50 regime 2 showed swelling and contraction of the reactor. Char in regime 1 showed that thermoplastic properties did not appear on char, while in regime 2, thermoplastic properties did appear on char. Experiment also showed that for PP 37,5 , char still contain oxygenated compounds, while for PP ge 37,5 , char contains no oxygen. Meanwhile, on plastic melt in PP 75 composition showed an oxygen mass transfer to the plastic melt from biomass. The results of all experiments show that co pyrolysis in regime 2 indicates a strong interaction between biomass and plastic leading to synergistic effect. "