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Bambang Heru Susanto
"[ABSTRAK
Industri bahan bakar bio berkembang dengan cepat sebagai konsekuensi dari naiknya harga minya dan meningkatnya kepedulian terhadapa perubahan iklim global. Produksi biodiesel dari transesterifikasi minyak nabati saat ini merupakan rute yang utama untuk menghasilkan bahan bakar nabati (BBN) untuk mesin diesel. Namun, biodiesel memiliki viskositas tinggi, titik kabaut dan tuang yang tinggi, emisi nitrogen oksida (NOx) yang lebih tinggi, densitas energi rendah dan keausan injektor/mesin tinggi. Beberapa rute telah dicoba untuk mengurangi viskositas, seperti blending minyak nabati dengan bahan bakar diesel, mikroemulsi dengan alkohol, pirolisis dan hidrodeoksigenasi (HDO). Solar terbarukan melalui HDO dapat dihasilkan dari beragam bahan baku minyak nabati seperti minyak sawit dan minyak jarak pagar tanpa mengorbankan kualitas bahan bakar. Reaksi pembentukan solar terbarukan melalui HDO minyak nabati melibatkan katalis untuk menurunkan energi aktivasi reaksi dan meningkatkan selektifitasnya. Jenis katalis yang digunakan didalam studi ini adalah katalis berbasi Pd dan berbasis NiMo yang disanggakan pada ZAL atau C. Metode microwave polyol process (MP) cocok untuk preparasi katalis berbasis Pd sedangkan metode rapid cooling (RC) cocok untuk preparasi katalis berbasis NiMo. HDO asam oleat sebagai senyawa model, minyak sawit dan minyak jarak pagar dilakukan pada suhu 375°C dan 400°C dengan tekanan H2 15 bar didalam reaktor autoclave 250 ml semibatch berpengaduk. Didalam HDO, katalis Pd/ZAL-1 selektif terhadap jalur dekarboksilasi sedangakan katalis NiMo/ZAL selektif terhadap jalur dekarboksilasi dan dekarbonilasi katalitik. Soalr terbarukan yang dihasilkan dari HDO memiliki densitas dan viskositas yang sesuai sesuai dan indeks setana yang lebih tinggi disertai dengan kesetaraan dalam kualitasnya dengan solar komersial turunan minyak bumi namun sedikit lebih rendah daripada solar terbarukan komersial (NExBTL®).;

ABSTRACT
The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®).;The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®)., The biofuels industry is growing rapidly as a result of high petroleum prices and increasing concerns about global climate change. Biodiesel production from trans-esterification of vegetable oils is currently the primary route for production of diesel engine biofuels from vegetable oils. However, biodiesel still has higher viscosity, higher cloud point and pour point, higher nitrogen oxides (NOx) emissions, lower energy density, and higher injector/engine wear. Several routes have been tried for reducing this viscosity, such as diluted vegetable oil with diesel fuel, microemulsification with alcohols, pyrolysis and hydrodeoxygenation (HDO). Renewable diesel through HDO can be produced from many kind of vegetable oil feeed stock such as palm oil (edible oil) and jatropha curcas (non-edible oil)without compromising fuel quality. Forming reaction of renewable diesel through HDO vegetable oil involves catalyst to decrease the activation energy of the reaction and increase its selectivity. The type of catalyst used in this study is Pd and NiMo supported on ZAL or C. Microwave polyol method (MP) is suitable for preparation of Pd-based catalyst while rapid cooling method (RC) is suitable for preparation of NiMo-based catalyst. The HDO of oleic acid as model compound, palm oil and jatropha curcas oil were carried out at temperature of 375°C and 400°C with H2 pressure of 15 bar in a 250 mL semibatch stirred autoclave reactor. In HDO, Pd/ZAL-1 catalyst was selective to decarboxylation route while NiMo/ZAL was selective to decarboxylation and catalytic decarbonilation. Renewable diesel synthesized through HDO have suitable density and viscosity and quite high cetane index with similar in their quality with comercial diesel derived from crude oil but slightly lower than comercial renewable diesel (NExBTL®).]"
2015
D2088
UI - Disertasi Membership  Universitas Indonesia Library
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Rahmayetty
"ABSTRAK
Sintesis poli asam laktat PLA menggunakan katalis lipase Candida rugosa dilakukan sebagai salah satu upaya untuk menghasilkan plastik biodegradable ramah lingkungan. dan berasal dari sumber daya terbarukan. Penggunaan lipase Candida rugosa sebagai pengganti katalis logam dalam polimerisasi telah berhasil mensintesis poli asam laktat PLA . Pelaksanaan kegiatan penelitian dilakukan melalui 3 tahapan proses. Tahapan awal adalah polikondensasi asam laktat dengan variasi temperatur untuk menghasilkan oligomer OLLA dengan berat molekul berbeda-beda. Tahap berikutnya adalah depolimerisasi dengan variasi temperatur, tekanan, jenis dan konsentrasi katalis serta berat molekul OLLA untuk menghasilkan laktida. Tahap terakhir adalah polimerisasi laktida menggunakan katalis lipase Candida rugosa dengan variasi temperatur dan konsentrasi lipase untuk menghasilkan PLA. Hasil penelitian menunjukkan bahwa polikondensasi pada temperatur konstan 150; 180; 200oC selama 4 jam dan temperatur bertahap 150oC selama 2 jam dan 180oC selama 2 jam menghasilkan OLLA dengan berat molekul Mw/Mn secara berurutan sebesar 1080/380; 1736/893; 2487/1375 dan 2820/2389. Tahap depolimerisasi menghasilkan laktida dengan stereoisomer L-laktida. Yield dan kemurnian laktida tertinggi masing-masing sebesar 78,8 dan 81,03 . Kondisi optimum tahap depolimerisasi adalah pada temperatur 210oC, tekanan 0,1 atm dan menggunakan katalis SnCl2 0,1 b/b serta berat molekul Mw/Mn OLLA sebesar 2820/2389. Polimerisasi pembukaan cincin L-laktida menggunakan katalis lipase Candida rugosa berlangsung optimum pada temperatur 90oC dengan konsentrasi lipase 2 b/b . Berat molekul PLA tertinggi didapatkan sebesar Mw/Mn 5428/2854 dengan yield 92,58 .

ABSTRACT
The synthesis of polylactic acid PLA using Candida rugosa lipase catalyst is performed as one of the efforts to produce environmentally friendly biodegradable plastic and derived from renewable resources. The use of Candida rugosa lipase as a substitute for metal catalyst in polymerization has successfully synthesized polylactic acid PLA . Implementation of research activities conducted through 3 stages of the process. The initial stage is the polycondensation of lactic acid with temperature variations to produce oligomers OLLA of varying molecular weights. The next step is depolymerization with variation of temperature, pressure, type and concentration of catalyst and molecular weight of OLLA to produce lactide. The last stage is lactide polymerization using Candida rugosa lipase catalyst with variation of temperature and lipase concentration to produce PLA. The results showed that polycondensation at constant temperature 150 180 200oC for 4 hours and gradually temperature 150oC for 2 hours and 180oC for 2 hours produced average molecular weight Mw Mn of 1080 380 1736 893 2487 1375 and 2820 2389, respectively. The depolymerization stage produced lactides with l lactide stereoisomers. The highest yields and purity of lactides were 78.8 and 81.03 , respectively. The optimum condition of the depolymerization step was at temperature of 210oC, pressure of 0.1 atm and using SnCl2 0.1 w w catalyst and average molecular weight Mw Mn of OLLA of 2820 2389. The ring opening polymerization of lactides using Candida rugosa lipase catalyst was optimum at 90 C with a lipase concentration of 2 w w . The highest molecular weight of PLA was obtained Mw Mn 5428 2854 and yield of PLA was 92.58 ."
2017
D2293
UI - Disertasi Membership  Universitas Indonesia Library