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Kinetika Reaksi Esterifikasi Palm Fatty Acid Distilate (PFAD) menjadi Biodiesel dengan Katalis Zeolit-Zirkonia Tersulfatasi Masduki; Sutijan; Arief Budiman
Jurnal Rekayasa Proses Vol 7, No 2 (2013)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (512.038 KB) | DOI: 10.22146/jrekpros.4953

Abstract

Krisis energi karena menipisnya cadangan minyak bumi mendorong manusia untuk berinovasi menciptakan sumber energi alternatif. Salah satu sumber energi alternatif yang potensial untuk dikembangkan adalah biodiesel. Produksi biodiesel skala besar terkendala oleh harga bahan baku yang mahal dan cenderung bersaing dengan kebutuhan pangan. Oleh karena itu perlu dicari bahan baku yang lebih murah dan tidak bersaing dengan kebutuhan pangan. Salah satu bahan yang dapat memenuhi kepentingan tersebut adalah Palm Fatty Acid Distilate (PFAD). Penelitian ini bertujuan untuk mempelajari kinetika reaksi esterifikasi PFAD menjadi biodiesel dengan katalis zeolit zirkonia tersulfatasi. Palm fatty acid distillate (PFAD) sebagai sumber asam lemak diesterifikasi menjadi biodiesel di dalam labu leher tiga yang dilengkapi dengan pemanas, pengaduk dan sistem refluks. Untuk memperoleh data kinetika, sampel diambil pada interval waktu 10 menit untuk dianalisis konversi asam lemaknya. Model kinetika reaksi esterifikasi PFAD menjadi biodiesel didekati dengan reaksi pseudo-homogen orde satu dan reaksi heterogen katalitik. Hasil penelitian menunjukkan bahwa kedua model kinetika yang diusulkan cukup sesuai dengan data percobaan. Hasil perhitungan model reaksi pseudo-homogen menghasilkan energi aktivasi sebesar 11,60 kJ/mol dan faktor pre-eksponensial sebesar 5,82.1016 s-1. Sedangkan untuk model reaksi heterogen katalitik diperoleh energi aktivasi sebesar 950,46 kJ/mol dan faktor pre-eksponensial sebesar 4,11 x 1010 dm6.gkat-1.mol-1.s-1. Konversi reaksi maksimum sebesar 75,68% diperoleh pada waktu reaksi 80 menit, suhu reaksi 65°C dengan konsentrasi katalis 3% dan perbandingan mol PFAD:metanol = 1:10. Kata kunci: biodiesel, kinetika, esterifikasi, palm fatty acid distillate, zeolit zirkonia tersulfatasi. Energy crisis due to depletion of crude oil resources has been a motivation for alternative energy search. Biodiesel becomes a potential among other alternative energy sources. However, large scale biodiesel production is hampered by the raw materials which become expensive and tent to compete with the source of food needs. Therefore, a search for an alternative inexpensive raw material is necessary. Palm fatty acid distilate (PFAD) is one of alternative raw materials can be utilized. The present work objective was to investigate reaction kinetics of PFAD esterification for biodiesel with zirconium sulphated zeolite as catalyst. PFAD as a source of fatty acid underwent esterification to produce biodiesel in a three necked flask equiped with heater, stirrer and reflux condensor. In order to study the reaction kinetics, samples were collected consecutively every 10 minutes and the conversion of the fatty acid in each sample was determined. Here, two esterification reaction models were proposed i.e. pseudo-homogeneous first order reaction model and heterogeneous catalytic reaction model. The results showed that calculated conversion for both proposed models were in a good agreement with the experimental data. The pseudo homogeneous reaction model has an activation energy of 11.60 kJ/mole and a pre-exponential factor of 5.821016 s1. Whereas, the heterogeneous reaction model has an activation energy of 950.46 kJ/mole and pre-exponential factor of 4.111010 dm6.g cat1.mol1.s1. The maximum conversion of 75.68% was obtained at 80 minute reaction time, at 65C with the use of 3% catalyst and a PFAD:methanol molar ratio of 1:10. Keywords: biodiesel, kinetics, esterification, palm fatty acid distillate, zirconium sulphated zeolite.
The Effect of Biomass-Water Ratio on Bio-crude Oil Production from Botryococcus braunii using Hydrothermal Liquefaction Process Laras Prasakti; Rochmadi Rochmadi; Arief Budiman
Jurnal Rekayasa Proses Vol 13, No 2 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (230.623 KB) | DOI: 10.22146/jrekpros.48963

Abstract

The increasing demand of energy in Indonesia has led to the urgency to conduct research and development in renewable energy. Biomass is one of the largest renewable energy sources in Indonesia. For biomass to energy conversion, hydrothermal liquefaction (HTL) has been considered as one of the potential methods where biomass is processed using subcritical water to produce bio-oil, aqueous phase, gas, and solid product. In this research, the effect of biomass-water ratio on hydrothermal liquefaction (HTL) process of microalgae Botryococcus braunii has been investigated. The HTL was conducted using biomass/water ratio 1:10, 1:20 and 1:30 with various holding time for each ratio. The product was bio-crude oil with similar characteristics to crude oil. Experimental results showed that biomass-water ratio affected the distribution of bio-crude oil yields. For biomass-water ratio of 1:10 and 1:20, it was found that bio-crude oil yields reached a maximum at 20 minutes, while the highest bio-crude oil yield of 4% was obtained at biomass-water ratio of 1:10. On the other hand, with biomass-water ratio of 1:30, bio-crude oil yield was continuously increasing with holding time until it reached the maximum yield of 4% at 40 minutes of holding time. The aforementioned results indicated that the highest bio-crude oil yield was obtained using biomass-water ratio 1:10 and 20 minutes of HTL processing time. A B S T R A KPeruraian anaerobik merupakan salah satu bidang riset yang sangat menarik perhatian dalam era krisis energi. Biogas tidak hanya menyediakan energi alternatif, tetapi juga dapat mencegah pencemaran akibat limbah organik. Limbah lemak susu adalah substrat yang potensial untuk proses peruraian anaerobik karena memiliki potensi biogas teoritis yang tinggi akibat kandungan lemaknya yang tinggi. Namun, peruraian anaerobik dari limbah organik dengan kandungan lemak yang tinggi memiliki tantangan tersendiri. Hambatan utama dalam peruraian anaerobik dari limbah lemak susu adalah kecenderungan untuk membentuk lapisan padatan yang tidak larut dan mengapung di bagian atas fase cair. Fenomena ini menghambat akses bakteri hidrolisis terhadap substrat. Saponifikasi adalah salah satu cara untuk meningkatkan kelarutan lapisan padatan tersebut, sehingga meningkatkan ketersediaan substrat untuk bakteri. Saponifikasi akan mengubah kandungan lemak menjadi sabun yang memiliki gugus fungsi polar maupun non-polar. Gugus fungsi yang bersifat polar akan meningkatkan kelarutan substrat dalam air. Studi ini mengevaluasi pengaruh dari berbagai dosis larutan basa yang ditambahkan sebagai reaktan selama perlakuan awal saponifikasi terhadap peruraian anaerobik limbah lemak susu. Kinetika proses peruraian anaerobik dianalisis dengan menggunakan model matematika. Variasi dosis yang diamati pengaruhnya untuk perlakuan awal saponifikasi adalah 0,04 mol basa/g sCOD; 0,02 mol basa/g sCOD; dan nol (tanpa perlakuan awal saponifikasi). Dari penelitian ini, terbukti bahwa saponifikasi berhasil meningkatkan kelarutan limbah lemak susu dan juga ditunjukkan oleh nilai konstanta hidrolisis (kH) 0,00782/hari lebih tinggi dua puluh kali lipat dibandingkan dengan nilai kH 0,00032/hari pada reaktor tanpa saponifikasi. Akan tetapi, penelitian ini juga mengindikasikan bahwa bakteri asidogenik bawaan substrat terhambat kinerjanya oleh paparan pH yang tinggi selama perlakuan awal saponifikasi berlangsung sehingga hasil gas metan yang diperoleh lebih rendah daripada reaktor kontrol.
Biochar from Slow Catalytic Pyrolysis of Spirulina platensis Residue: Effects of Temperature and Silica-Alumina Catalyst on Yield and Characteristics Siti Jamilatun; Ilham Mufandi; Arief Budiman; Suhendra Suhendra
Jurnal Rekayasa Proses Vol 14, No 2 (2020)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.56221

Abstract

The use of biochar varies on its ability as an adsorbent which adsorbs liquid or gas molecules. Biochar from Spirulina platensis residue (SPR) as an energy source, as its richness in nutrients, can be used as fertilizer and maintain water resources in plantations. Biochar can be used as an intermediary for the synthesis of nanotubes, activated carbon, carbon black, and carbon fiber. One of the essential things to be considered in the application of activated carbon from SPR is char’s characteristics. This study aimed to obtain data on the biochar and components from the pyrolysis of Spirulina platensis residue. The study was conducted in a fixed-bed reactor with electric heaters with a variety of temperatures (300-700 ⁰C) and the amount of silica-alumina catalyst (0-20%). The biochar weight was obtained by weighing the char formed at the end of the pyrolysis. The char characteristics were obtained by the surface area, total pore volume, and pore size analysis. Based on the study results, the relationship between temperature and the amount of catalyst on the characteristics of biochar was studied. The higher the pyrolysis temperature, the less biochar. Also, the use of catalysts can reduce the amount of biochar. The higher the temperature, the higher the surface area and the total pore volume while the pore radius was reduced. The optimum condition for maximum biochar yield in non-catalytic pyrolysis at a temperature of 300 ⁰C was 49.86 wt.%. The surface area, the total pore volume, and the pore radius at 700 ⁰C catalytic pyrolysis with 5% silica-alumina was obtained as 36.91 m2/g, 0.052 cm3/g, and 2.68 nm, respectively.Keywords: biochar; pore radius; silica-alumina; surface area; total pore volumeA B S T R A KPenggunaan biochar bervariasi pada kemampuannya sebagai adsorben dalam menjerap molekul cairan atau gas. Biochar dari residu Spirulina platensis merupakan sumber energi, karena kaya akan unsur hara, dapat digunakan sebagai pupuk dan pemeliharaan sumber daya air di perkebunan. Biochar dapat juga digunakan sebagai perantara untuk sintesis nanotube, karbon aktif, carbon black, dan serat karbon. Salah satu hal penting yang harus diperhatikan dalam aplikasi karbon aktif dari SPR adalah karakteristik arang. Penelitian ini bertujuan untuk mendapatkan data biochar dan komponen dari pirolisis residu Spirulina platensis. Penelitian dilakukan di reaktor fixed-bed dengan pemanas listrik dengan variasi suhu (300-700 ⁰C) dan jumlah katalis silika-alumina (0-20%). Berat biochar diperoleh dengan cara menimbang arang yang terbentuk pada akhir pirolisis. Sedangkan karakteristik arang diperoleh dari analisis luas permukaan, volume pori total, dan ukuran pori. Berdasarkan hasil studi hubungan antara suhu dan jumlah katalis terhadap karakteristik biochar yang telah diteliti, semakin tinggi suhu pirolisis maka biochar semakin sedikit. Selain itu, penggunaan katalis dapat mengurangi jumlah biochar. Sebaliknya, semakin tinggi suhu semakin besar luas permukaan, dan volume pori total serta radius pori-pori semakin berkurang. Kondisi optimum untuk biochar maksimum pada pirolisis non katalitik pada suhu  300 ⁰C adalah 49,86 wt.%. Luas permukaan, total volume pori, dan radius pori pada suhu 700 ⁰C untuk pirolisis katalitik silika-alumina 5% diperoleh masing-masing sebesar 36,91 m2/g, 0,052 cm3/g, dan 2,68 nm.Kata kunci: biochar; luas permukaan; radius pori; silika-alumina; total volume pori  
The Impact of Electric Vehicle on Road Transportation in Indonesia: Energy Demand and CO2 Emission Arif Yulianto Widi Kurniawan; Ahmad Agus Setiawan; Arief Budiman
JPSE (Journal of Physical Science and Engineering) Vol 5, No 2 (2020): JPSE (Journal of Physical Science and Engineering)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Light Duty Vehicle (LDV) for road transportation in Indonesia is the biggest energy consumption with most of the energy carriers from refined fuel oil with high CO2 emission. Battery Electric Vehicle (BEV) is one of the alternatives to reduce oil consumption and CO2 emission on the road transportation sector. This research is carried to analyse impact on BEV on energy demand and carbon emission. Modified Mobility Model (MoMo) with PUCE methods was developed to projecting road transportation demand in Indonesia. This research shows that road transportation will reach 519 MBoe in 2040 with 83.6% from refined fuel oil. With moderate EV, energy will be reduced by 31 MBoe (6%), and refined fuel oil reduced by 8.5%. With a high EV scenario, energy will be reduced by 57 MBoe (14%) and refined fuel oil reduced by 16%. CO2 emission will be reduced up to 4.8 to 8.8% in 2040.DOI: http://dx.doi.org/10.17977/um024v5i22020p036
Pemodelan dan Simulasi Kinetika Reaksi Alkoholisis Minyak Jarak Pagar (Jatropha Curcas) dengan Katalisator Zirkonia Tersulfatasi Heri Rustamaji; Hary Sulistyo; Arief Budiman
Jurnal Rekayasa Proses Vol 4, No 1 (2010)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.571

Abstract

Biodiesel berhasil diproduksi dengan alkoholisis minyak jarak menggunakan katalisator zirkonia tersulfatasi. Proses alkoholisis dilakukan dalam suatu reaktor batch yang dilengkapi dengan pemanas, termokopel, pengaduk, termostat, dan pengambil sampel. Reaktor batch diisi dengan minyak jarak pagar, metanol dan katalisator. Reaksi selanjutnya dilakukan selama 120 menit dan sampel diambil setiap 15 menit. Model kinetika reaksi kimia disusun dan diselesaikan dengan MATLAB. Nilai faktor frekuensi tumbukan untuk reaksi tiga tahap adalah 5,13 x 103; 5,682 x 103, dan 2,534 x 103 (cm3/mgek) (cm3/g.kat/min). Sementara itu, nilai energi aktivasi reaksi berturut-turut adalah 4.176; 4.309,809 dan 6.018,623 kal/mol. Hasil simulasi menunjukkan bahwa tahap pengurangan trigliserida menjadi digliserida adalah tahap paling cepat dan tahap pengurangan monogliserida menjadi gliserol adalah tahap paling lambat.Kata kunci: minyak jarak pagar, alkoholisis, model kinetika reaksi, katalisator asam padatJatropha oil is a very potential source of biodiesel fuel that can be processed through alcoholysis. In the present work, a study on alcoholysis of Jatropha oil with the use of solid acid catalyst was conducted in a wellmixed batch reactor. The study involved varying reaction temperatures of 100°C to 140°C, ethanol-oil molar ratio of 9, agitation speed of 1000 rpm and catalyst loading of 3% with respect to the oil. The reaction was carried out for 120 minutes; meanwhile samples were taken from the reactor every 15 minutes for glycerol analysis. In order to predict kinetics parameter of the alcoholysis reaction, a mathematical model of consecutive reactions was developed. The Matlab software was used to solve the simultaneous differential equations. Over the range of variables used in the experiment, the mathematical model was able to fit the experimental data quite well. The calculation results showed that the values of collision frequency factor for the consecutive reactions are 5.13 x 103; 5.682 x 103, and 2.534 x 103 (cm3/mgek) (cm3/g.cat/min). Meanwhile, the activation energies for the consecutive reaction are 4,176; 4,310 and 6,019 cal/mol. Keywords: jatropha curcas, methanolysis, kinetics modeling, solid acid catalyst
Kinetika Reaksi Alkyd Resin Termodifikasi Minyak Jagung dengan Asam Phtalat Anhidrat Heri Heriyanto; Rochmadi Rochmadi; Arief Budiman
Jurnal Rekayasa Proses Vol 5, No 1 (2011)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.1892

Abstract

Reaksi esterifikasi anhidrida phtalat dengan monogliserida merupakan reaksi kondensasi membentuk polimer dengan rantai linier. Penelitian ini bertujuan untuk mempelajari kinetika reaksi alkid resin termodifikasi minyak jagung tanpa menggunakan katalis. Proses penelitian ada dua tahap yaitu tahap pertama reaksi alkoholisis dan tahap kedua reaksi esterifikasi. Tahap alkoholisis diawali dengan mereaksikan minyak jagung dan gliserol dengan perbandingan molar 1:2 pada suhu 250°C. Sampel diambil pada selang waktu 30 menit selama 3 jam untuk dianalisis kadar gliserol bebasnya dengan metode iodometri (FBI-AO2-03). Tahap esterifikasi adalah mencampurkan anhidrida phtalat ke dalam reaktor batch dengan perbandingan molar gliserol : anhidrida phtalat 3:2. Sampel dianalisis kadar gugus OH- dengan metode asetat anhidrida. Peubah-ubah yang dipelajari meliputi variasi suhu dari 230°C – 260°C dan variasi perbandingan ekivalen OH/COOH dari 1 – 1,25. Berdasarkan hasil penelitian diambil kesimpulan bahwa minyak jagung dan gliserol dapat dialkoholisis tanpa menggunakan katalis pada kisaran suhu 230°C – 260°C. Pengaruh suhu terhadap konstanta kecepatan reaksi dinyatakan dengan persamaan Arrhenius adalah sebagai berikut : k1=1,4647×104 exp (-8237,7/T) (g/mgek.men) k4=2,1398×109 exp (-14142/T) (g/mgek.men) Kata kunci: alkoholisis, esterifikasi, minyak jagung, gliserol, anhidrida phtalat Esterification of phthalic anhydrate with monoglyceride is a condensation reaction to form a linear chain polymer. The present work aimed at investigating reaction kinetics of alkyd resin modified with corn oil in the absence of catalyst. The work consisted of two steps i.e. alcoholysis and esterification. In the alcoholysis step, corn oil and glycerol were brought into reaction with a molar ratio of 1:2 at 250°C. Every 30 minutes during 3 hour reaction, reaction products were sampled to analyse the remaining free glycerol by iodometry method (FBI-AO2-03). In the esterification step, phthalic anhydrate was put in the batch reactor with a glycerol-phthalic anhydrate molar of 3:2. Samples were taken and the hydroxyl ions were analysed by acetate anhydrate method. The variables investigated in the present work were reaction temperatures varied from 230°C to 260°C and equivalent OH/COOH ratio from 1 to 1.25. Experimental results showed that alcoholysis of corn oil and glycerol could be carried out in a temperature range of 230°C to 260°C without the presence of catalyst. The effect of temperature on the reaction rate constant of monoglyceride and phthalic ester formation could be respectively written in the Arrhenius correlations as follows: k1 = 1.4647.104 exp (-8237.7/T) g/mgeq.min k4 = 2.1398.109 exp (-14142/T) g/mgeq.min Keywords: alcoholysis, esterification, corn oil, glycerol, phthalic anhydrate
Kinetika Reaksi Esterifikasi Palm Fatty Acid Distilate (PFAD) menjadi Biodiesel dengan Katalis Zeolit-Zirkonia Tersulfatasi Masduki; Sutijan; Arief Budiman
Jurnal Rekayasa Proses Vol 7, No 2 (2013)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.4953

Abstract

Krisis energi karena menipisnya cadangan minyak bumi mendorong manusia untuk berinovasi menciptakan sumber energi alternatif. Salah satu sumber energi alternatif yang potensial untuk dikembangkan adalah biodiesel. Produksi biodiesel skala besar terkendala oleh harga bahan baku yang mahal dan cenderung bersaing dengan kebutuhan pangan. Oleh karena itu perlu dicari bahan baku yang lebih murah dan tidak bersaing dengan kebutuhan pangan. Salah satu bahan yang dapat memenuhi kepentingan tersebut adalah Palm Fatty Acid Distilate (PFAD). Penelitian ini bertujuan untuk mempelajari kinetika reaksi esterifikasi PFAD menjadi biodiesel dengan katalis zeolit zirkonia tersulfatasi. Palm fatty acid distillate (PFAD) sebagai sumber asam lemak diesterifikasi menjadi biodiesel di dalam labu leher tiga yang dilengkapi dengan pemanas, pengaduk dan sistem refluks. Untuk memperoleh data kinetika, sampel diambil pada interval waktu 10 menit untuk dianalisis konversi asam lemaknya. Model kinetika reaksi esterifikasi PFAD menjadi biodiesel didekati dengan reaksi pseudo-homogen orde satu dan reaksi heterogen katalitik. Hasil penelitian menunjukkan bahwa kedua model kinetika yang diusulkan cukup sesuai dengan data percobaan. Hasil perhitungan model reaksi pseudo-homogen menghasilkan energi aktivasi sebesar 11,60 kJ/mol dan faktor pre-eksponensial sebesar 5,82.1016 s-1. Sedangkan untuk model reaksi heterogen katalitik diperoleh energi aktivasi sebesar 950,46 kJ/mol dan faktor pre-eksponensial sebesar 4,11 x 1010 dm6.gkat-1.mol-1.s-1. Konversi reaksi maksimum sebesar 75,68% diperoleh pada waktu reaksi 80 menit, suhu reaksi 65°C dengan konsentrasi katalis 3% dan perbandingan mol PFAD:metanol = 1:10. Kata kunci: biodiesel, kinetika, esterifikasi, palm fatty acid distillate, zeolit zirkonia tersulfatasi. Energy crisis due to depletion of crude oil resources has been a motivation for alternative energy search. Biodiesel becomes a potential among other alternative energy sources. However, large scale biodiesel production is hampered by the raw materials which become expensive and tent to compete with the source of food needs. Therefore, a search for an alternative inexpensive raw material is necessary. Palm fatty acid distilate (PFAD) is one of alternative raw materials can be utilized. The present work objective was to investigate reaction kinetics of PFAD esterification for biodiesel with zirconium sulphated zeolite as catalyst. PFAD as a source of fatty acid underwent esterification to produce biodiesel in a three necked flask equiped with heater, stirrer and reflux condensor. In order to study the reaction kinetics, samples were collected consecutively every 10 minutes and the conversion of the fatty acid in each sample was determined. Here, two esterification reaction models were proposed i.e. pseudo-homogeneous first order reaction model and heterogeneous catalytic reaction model. The results showed that calculated conversion for both proposed models were in a good agreement with the experimental data. The pseudo homogeneous reaction model has an activation energy of 11.60 kJ/mole and a pre-exponential factor of 5.821016 s1. Whereas, the heterogeneous reaction model has an activation energy of 950.46 kJ/mole and pre-exponential factor of 4.111010 dm6.g cat1.mol1.s1. The maximum conversion of 75.68% was obtained at 80 minute reaction time, at 65C with the use of 3% catalyst and a PFAD:methanol molar ratio of 1:10. Keywords: biodiesel, kinetics, esterification, palm fatty acid distillate, zirconium sulphated zeolite.
The Effect of Biomass-Water Ratio on Bio-crude Oil Production from Botryococcus braunii using Hydrothermal Liquefaction Process Laras Prasakti; Rochmadi Rochmadi; Arief Budiman
Jurnal Rekayasa Proses Vol 13, No 2 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (230.623 KB) | DOI: 10.22146/jrekpros.48963

Abstract

The increasing demand of energy in Indonesia has led to the urgency to conduct research and development in renewable energy. Biomass is one of the largest renewable energy sources in Indonesia. For biomass to energy conversion, hydrothermal liquefaction (HTL) has been considered as one of the potential methods where biomass is processed using subcritical water to produce bio-oil, aqueous phase, gas, and solid product. In this research, the effect of biomass-water ratio on hydrothermal liquefaction (HTL) process of microalgae Botryococcus braunii has been investigated. The HTL was conducted using biomass/water ratio 1:10, 1:20 and 1:30 with various holding time for each ratio. The product was bio-crude oil with similar characteristics to crude oil. Experimental results showed that biomass-water ratio affected the distribution of bio-crude oil yields. For biomass-water ratio of 1:10 and 1:20, it was found that bio-crude oil yields reached a maximum at 20 minutes, while the highest bio-crude oil yield of 4% was obtained at biomass-water ratio of 1:10. On the other hand, with biomass-water ratio of 1:30, bio-crude oil yield was continuously increasing with holding time until it reached the maximum yield of 4% at 40 minutes of holding time. The aforementioned results indicated that the highest bio-crude oil yield was obtained using biomass-water ratio 1:10 and 20 minutes of HTL processing time. A B S T R A KPeruraian anaerobik merupakan salah satu bidang riset yang sangat menarik perhatian dalam era krisis energi. Biogas tidak hanya menyediakan energi alternatif, tetapi juga dapat mencegah pencemaran akibat limbah organik. Limbah lemak susu adalah substrat yang potensial untuk proses peruraian anaerobik karena memiliki potensi biogas teoritis yang tinggi akibat kandungan lemaknya yang tinggi. Namun, peruraian anaerobik dari limbah organik dengan kandungan lemak yang tinggi memiliki tantangan tersendiri. Hambatan utama dalam peruraian anaerobik dari limbah lemak susu adalah kecenderungan untuk membentuk lapisan padatan yang tidak larut dan mengapung di bagian atas fase cair. Fenomena ini menghambat akses bakteri hidrolisis terhadap substrat. Saponifikasi adalah salah satu cara untuk meningkatkan kelarutan lapisan padatan tersebut, sehingga meningkatkan ketersediaan substrat untuk bakteri. Saponifikasi akan mengubah kandungan lemak menjadi sabun yang memiliki gugus fungsi polar maupun non-polar. Gugus fungsi yang bersifat polar akan meningkatkan kelarutan substrat dalam air. Studi ini mengevaluasi pengaruh dari berbagai dosis larutan basa yang ditambahkan sebagai reaktan selama perlakuan awal saponifikasi terhadap peruraian anaerobik limbah lemak susu. Kinetika proses peruraian anaerobik dianalisis dengan menggunakan model matematika. Variasi dosis yang diamati pengaruhnya untuk perlakuan awal saponifikasi adalah 0,04 mol basa/g sCOD; 0,02 mol basa/g sCOD; dan nol (tanpa perlakuan awal saponifikasi). Dari penelitian ini, terbukti bahwa saponifikasi berhasil meningkatkan kelarutan limbah lemak susu dan juga ditunjukkan oleh nilai konstanta hidrolisis (kH) 0,00782/hari lebih tinggi dua puluh kali lipat dibandingkan dengan nilai kH 0,00032/hari pada reaktor tanpa saponifikasi. Akan tetapi, penelitian ini juga mengindikasikan bahwa bakteri asidogenik bawaan substrat terhambat kinerjanya oleh paparan pH yang tinggi selama perlakuan awal saponifikasi berlangsung sehingga hasil gas metan yang diperoleh lebih rendah daripada reaktor kontrol.
Biochar from Slow Catalytic Pyrolysis of Spirulina platensis Residue: Effects of Temperature and Silica-Alumina Catalyst on Yield and Characteristics Siti Jamilatun; Ilham Mufandi; Arief Budiman; Suhendra Suhendra
Jurnal Rekayasa Proses Vol 14, No 2 (2020)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.56221

Abstract

The use of biochar varies on its ability as an adsorbent which adsorbs liquid or gas molecules. Biochar from Spirulina platensis residue (SPR) as an energy source, as its richness in nutrients, can be used as fertilizer and maintain water resources in plantations. Biochar can be used as an intermediary for the synthesis of nanotubes, activated carbon, carbon black, and carbon fiber. One of the essential things to be considered in the application of activated carbon from SPR is char’s characteristics. This study aimed to obtain data on the biochar and components from the pyrolysis of Spirulina platensis residue. The study was conducted in a fixed-bed reactor with electric heaters with a variety of temperatures (300-700 ⁰C) and the amount of silica-alumina catalyst (0-20%). The biochar weight was obtained by weighing the char formed at the end of the pyrolysis. The char characteristics were obtained by the surface area, total pore volume, and pore size analysis. Based on the study results, the relationship between temperature and the amount of catalyst on the characteristics of biochar was studied. The higher the pyrolysis temperature, the less biochar. Also, the use of catalysts can reduce the amount of biochar. The higher the temperature, the higher the surface area and the total pore volume while the pore radius was reduced. The optimum condition for maximum biochar yield in non-catalytic pyrolysis at a temperature of 300 ⁰C was 49.86 wt.%. The surface area, the total pore volume, and the pore radius at 700 ⁰C catalytic pyrolysis with 5% silica-alumina was obtained as 36.91 m2/g, 0.052 cm3/g, and 2.68 nm, respectively.Keywords: biochar; pore radius; silica-alumina; surface area; total pore volumeA B S T R A KPenggunaan biochar bervariasi pada kemampuannya sebagai adsorben dalam menjerap molekul cairan atau gas. Biochar dari residu Spirulina platensis merupakan sumber energi, karena kaya akan unsur hara, dapat digunakan sebagai pupuk dan pemeliharaan sumber daya air di perkebunan. Biochar dapat juga digunakan sebagai perantara untuk sintesis nanotube, karbon aktif, carbon black, dan serat karbon. Salah satu hal penting yang harus diperhatikan dalam aplikasi karbon aktif dari SPR adalah karakteristik arang. Penelitian ini bertujuan untuk mendapatkan data biochar dan komponen dari pirolisis residu Spirulina platensis. Penelitian dilakukan di reaktor fixed-bed dengan pemanas listrik dengan variasi suhu (300-700 ⁰C) dan jumlah katalis silika-alumina (0-20%). Berat biochar diperoleh dengan cara menimbang arang yang terbentuk pada akhir pirolisis. Sedangkan karakteristik arang diperoleh dari analisis luas permukaan, volume pori total, dan ukuran pori. Berdasarkan hasil studi hubungan antara suhu dan jumlah katalis terhadap karakteristik biochar yang telah diteliti, semakin tinggi suhu pirolisis maka biochar semakin sedikit. Selain itu, penggunaan katalis dapat mengurangi jumlah biochar. Sebaliknya, semakin tinggi suhu semakin besar luas permukaan, dan volume pori total serta radius pori-pori semakin berkurang. Kondisi optimum untuk biochar maksimum pada pirolisis non katalitik pada suhu  300 ⁰C adalah 49,86 wt.%. Luas permukaan, total volume pori, dan radius pori pada suhu 700 ⁰C untuk pirolisis katalitik silika-alumina 5% diperoleh masing-masing sebesar 36,91 m2/g, 0,052 cm3/g, dan 2,68 nm.Kata kunci: biochar; luas permukaan; radius pori; silika-alumina; total volume pori  
Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina Platensis Residue Siti Jamilatun; Budhijanto Budhijanto; Rochmadi Rochmadi; Arief Budiman
International Journal of Renewable Energy Development Vol 6, No 3 (2017): October 2017
Publisher : Center of Biomass & Renewable Energy, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/ijred.6.3.193-201

Abstract

 Analysis of thermal decomposition and pyrolisis reaction kinetics of Spirulina platensis residue (SPR) was performed using Thermogravimetric Analyzer. Thermal decomposition was conducted with the heating rate of 10, 20, 30, 40 and 50oC/min from 30 to 1000oC. Thermogravimetric (TG), Differential Thermal Gravimetric (DTG), and Differential Thermal Analysis (DTA) curves were then obtained. Each of the curves was divided into 3 stages. In Stage I, water vapor was released in endothermic condition. Pyrolysis occurred in exothermic condition in Stage II, which was divided into two zones according to the weight loss rate, namely zone 1 and zone 2. It was found that gasification occurred in Stage III in endothermic condition. The heat requirement and heat release on thermal decomposition of SPR are described by DTA curve, where 3 peaks were obtained for heating rate 10, 20 and 30°C/min and 2 peaks for 40 and 50°C/min, all peaks present in Zone 2. As for the DTG curve, 2 peaks were obtained in Zone 1 for similar heating rates variation. On the other hand, thermal decomposition of proteins and carbohydrates is indicated by the presence of peaks on the DTG curve, where lignin decomposition do not occur due to the low lipid content of SPR (0.01wt%). The experiment results and calculations using one-step global model successfully showed that the activation energy (Ea) for the heating rate of 10, 20, 30, 40 and 50oC/min for zone 1 were 35.455, 41.102, 45.702, 47.892 and 47.562 KJ/mol, respectively, and for zone 2 were 0.0001428, 0.0001240, 0.0000179, 0.0000100 and 0.0000096 KJ/mol, respectively.Keywords: Spirulina platensis residue (SPR), Pyrolysis, Thermal decomposition, Peak, Activation energy.Article History: Received June 15th 2017; Received in revised form August 12th 2017; Accepted August 20th 2017; Available onlineHow to Cite This Article: Jamilatun, S., Budhijanto, Rochmadi, and Budiman, A. (2017) Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina platensis Residue, International Journal of Renewable Energy Development 6(3), 193-201.https://doi.org/10.14710/ijred.6.3.193-201