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"Nox terbentuk dari kombinasi N2 dan O2 paa temperatur dan tekanan tinggi yang terjadi pada proses pembakaran bahan bakar. Sumber NOx diantarannya adalah NO, NO2 dan N2O mempunyai peranan penting dalam perubahan kimia dari lapisan ozon."

"Konversi minyak kelapa sawit menjadi fraksi bensin merupakan salah satu upaya pencarian energi alternatif sebagai pengganti suplai energi berbasis minyak bumi. Hasil penelitian terdahulu menunjukkan minyak kelapa sawit dapat direngkah menjadi hidrokarbon melalui reaksi perengkahan katalik dengan katalis asam, salah satunya adalah katalis γ-alumina. Dalam penelitian ini dilakukan reaksi minyak sawit dengan katalis γ-alumina di dalam reaktor tumpak berpengaduk yang dilakukan dengan variasi perbandingan berat minyak/katalis 100:1, 75:1 dan 50:1 pada variasi suhu reaksi antara 260 - 340 °C dalam variasi waktu reaksi 1-2 jam. Pasca reaksi perengkahan, produk bensin alternatif ini (biogasoline) diperoleh setelah perlakuan distilasi tumpak 2 tahap. Uji densitas dan viskositas produk ini menunjukkan hasil yang mendekati sifat fisika bensin komersial. Dari hasil uji densitas, viskositas, dan Fourier Transform Infra Red Spektrofotometer (FTIR) produk reaksi perengkahan dapat disimpulkan bahwa produk optimum reaksi terjadi pada perbandingan berat minyak/katalis 100:1 dalam waktu 1.5 jam dan suhu 340 °C, dan hasil uji kandungan produk dengan FTIR, Gas Chromatography (GC), dan Gas Chromatografi-Mass Spectrofotometer (GC-MS) menunjukkan adanya kemiripan dengan kandungan bensin komersial. Berdasarkan hasil uji tersebut, produksi biogasoline pada penelitian ini memiliki yield 11.8% (v/v) dan konversi 28.0% (v/v ) terhadap umpan minyak sawit dengan bilangan oktana produknya sebesar 61.0.

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Biogasoline Production from Palm Oil Via Catalytic Hydrocracking over Gamma-Alumina Catalyst. Bio gasoline conversion from palm oil is an alternative energy resources method which can be substituted fossil fuel base energy utilization. Previous research resulted that palm oil can be converted into hydrocarbon by catalytic cracking reaction with γ-alumina catalyst. In this research, catalytic cracking reaction of palm oil by γ-alumina catalyst is done in a stirrer batch reactor with the oil/catalyst weight ratio variation of 100:1, 75:1, and 50:1; at suhue variation of 260 to 340°C and reaction time variation of 1 to 2 hour. Post cracking reaction, bio gasoline yield could be obtained after 2 steps batch distillation. Physical property test result such as density and viscosity of this cracking reaction product and commercial gasoline tended a closed similarity. According to result of the cracking product?s density, viscosity and FTIR, it can conclude that optimum yield of the palm oil catalytic cracking reaction could be occurred when oil/catalyst weight ratio 100:1 at 340°C in 1.5 hour and base on this bio gasoline?s FTIR, GC and GC-MS identification results, its hydrocarbons content was resembled to the commercial gasoline. This palm oil catalytic cracking reaction shown 11.8% (v/v) in yield and 28.0% (v/v) in conversion concern to feed palm oil base and produced a 61.0 octane number?s bio gasoline."

"The effect of precipitant and ultrasonic over Ni7CeO,-MgO-La,0/A503 catalyst was studied in an atmospheric fixed-bed reactor for partial oxidation of methane. Two types of precipitant used in this work were Na2C)3 and NH4OH2 and the length of ultrasonic iradiation was 60 minutes (1 hour). The bulk surface area, nickel particle diameter, nickel dispersion and morphology of the catalysts were investigated by various characterization techniques, including BET] XRD, H; chemisorption and SEM The partial oxidation of methane to syngas was done at 800 ?C atmospheric pressure and the feed ratio (CH/01) was 2 : 1.2. It was found that catalysts prepared by using NH4OH2 precipitant have pore size that larger than those of catalysts prepared using Na,CO, precipitant. The effect of ultrasonic on the catalysts showed that ultrasonic irradiation enhanced the surface area of the catalyst and the nickel dispersion. SEM analyses shown changes of the catalyst morphology, i.e. the particle of the catalyst became smaller and more uniform because of the ultrasonic irradiation. Catalyst prepared using NH,0H precipitant and irradiated shown the best performance with 96% methane conversion."

"Ox terbentuk dari kombinasi N2 dan O2 pada temperatur dan tekanan tinggi, yang terjadi pada proses pembakaran bahan bakar. Sumber NOx diantaranya adalah NO, NO2, dan N2O mempunyai peranan penting dalam perubahan kimia dari lapisan ozon. N2O merupakan produk samping dari penggunaan nitrogen di pertanian. N2O dapat diemisikan dari tanah pertanian, juga dapat tertimbun di tanah on-pertanian, dan secara biokimia dikonversikan serta diemisikan ke atmosfir. Biofiltrasi merupakan teknologi biologis yang paling sering digunakan dalam pengelolaan polusi udara. Biofiltrasi adalah proses pengolahan polutan gas di dalam suatu unggun medium dimana polutan akan mengalami degradasi oleh mikroorganisme. Saat ini, penelitian biofilter yang ada lebih difokuskan pada reduksi NH3 dan H2S. Sedikit sekali peneliti yang tertarik untuk mengaplikasikannya dalam reduksi NOx. Untuk mendukung aplikasi lebih lanjut, dibutuhkan studi pada skala Lab. dan pilot untuk optimasi parameter operasi. Kajian yang lebih mendalam sebaiknya disertai dengan pengembangan model yang mampu menjelaskan dan memprediksi perilaku dari sistem biofilter pada kondisi steady-state ataupun transient.

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NOx formed from combination of N2 and O2 at temperature and high pressure, in combustion process of fuel. Source of NOx such as NO, NO2, and N2O has important role in chemical change of ozone layer. N2 O is a product from usage of nitrogen in agriculture. N2O can be emission from farmland, also can be piled up in non-agricultural soil, and biochemically converted and emission to atmosphere. Biofiltration is biological technology which very often used in air pollution control. Biofiltration is process of eliminate gas pollutant in a filter medium where pollutant will degrade by microorganism. In the recent years, research biofilter focused at reduction of NH3 and H2S. Only several researchers interested to applicate it in NOx reduction. To support further application, study at Laboratory scale and pilot scale for operation parameter optimization is needed. A better study ccompanied with development of model capable to explain and predicts behavior of biofilter system at steady-state and or transient condition."

"Produk pelumas, sampai sekarang sebagian besar masih berasal dari petroleum, namun meningkatnya kepedulian terhadap dampaknya terhadap konservasi ekologi mendorong dikembangkannya pelumas ramah lingkungan berbasis minyak nabati. Sebagai bahan pelumas, minyak nabati memiliki keunggulan sifat antiwear yang baik, biodegradable dan tak beracun, sedangkan kelemahannya adalah rendah ketahanan oksidasi dan buruk fluiditasnya pada suhu rendah. Minyak nabati dapat ditransformasikan menjadi pelumas ramah lingkungan berunjuk kerja tinggi melalui modifikasi gugus karbonilnya, misalnya, metilolpropan ester yang dapat diproduksi dengan cara menggantikan gliserol dari trigliserida dengan metilolpropan, atau melalui modifikasiikatan rangkap karbon-karbon pada rantai asam lemaknya, misalnya reaksi hidrogensasi selektif, dimerisasi, epoksidasi dan lain -lain. Namun biaya proses modifikasi yang tinggi mendorong penggunaan minyak nabati langsung, yaitu minyak nabati yang memiliki kandungan asam oleat tinggi. Tulisan ini juga mendiskusikan kemung kinan pemanfaatan minyak sawit sebagai pelumas, dengan mempertimbangkan karakteristik spesifiknya sebagai minyak nabati daerah tropis.

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Most of lubricating oils are based on petroleum, but awareness and concern over the usage of petroleum base products and their impact on environment has created an opportunity to develop eco-friendly lubricant from vegetable oil. As raw material of lubricant, the vegetable oils provides many advantages such as good antiwear property, biodegradability, non toxic, but it has low oxidation resistance and poor fluidity at low temperature. Vegetable oil can be transformed to high performance eco-friendly lubricant, via modification of carbonyl group, such as trimethy lolpropane ester which can be produced by replacing glycerol of triglyceride with trimethylolpropane, or via modification of carbon-carbon double bond in fatty acid chain of triglyceride such as selective hydrogenation, dimerization, epoxidation etc etera. Modified vegetable oil, such as synthetic ester may offer high performance lubricant, but its process production cost can be prohibitively high, therefore it gives rise to the direct us age of high olein vegetable oil for lubricant formulation. This paper also discusses the application of palm oil for lubricant, by considering its specific characterisitic as vegetable oil from tropical region."

"Objectives of this research are mainly to study impacts of acidity strength (by varying amount of precipitant and loading Al-Si) and the effect of nickel particle size (by varying calcinations temperature) on decomposition reaction performances. In this research, high-nickel-loaded catalyst is prepared with two methods. Ni-Cu/Al catalysts were prepared with co-precipitation method. While the Ni-Cu/Al-Si catalyst were prepared by combined co-precipitation and sol-gel method. The direct cracking of methane was performed in 8mm quartz fixed bed reactor at atmospheric pressure and 500-700°C. The main results showed that the Al content of catalyst increases with the increasing amount of precipitant. The activity of catalyst increases with the increasing of catalyst?s acidity to the best possible point, and then increasing of acidity will reduce the activity of catalyst. Ni-Cu/4Al and Ni-Cu/11Al deactivated in a very short time hence produced fewer amount of nanocarbon, while Ni-Cu/15Al was active in a very long period. The most effective catalyst is Ni-Cu/22Al, which produced the biggest amount of nanocarbon (4.15 g C/g catalyst). Ni catalyst diameter has significant effect on reaction performances mainly methane conversion and product yield. A small Ni crystal size gave a high methane conversion, a fast deactivation and a low carbon yield. Large Ni particle diameter yielded a slow decomposition and low methane conversion. The highest methane conversion was produced by catalyst diameter of 4 nm and maximum yield of carbon of 4.08 g C/ g catalyst was achieved by 15.5 nm diameter of Ni catalyst."

"Objectives of this research are mainly to study impacts of acidity strength (by varying amount of precipitant and loading Al-Si) and the effect of nickel particle size (by varying calcinations temperature) on decomposition reaction performances. In this research, high-nickel-loaded catalyst is prepared with two methods. Ni-Cu/Al catalysts were prepared with co-precipitation method. While the Ni-Cu/Al-Si catalyst were prepared by combined co-precipitation and sol-gel method. The direct cracking of methane was performed in 8mm quartz fixed bed reactor at atmospheric pressure and 500-700°C. The main results showed that the Al content of catalyst increases with the increasing amount of precipitant. The activity of catalyst increases with the increasing of catalyst?s acidity to the best possible point, and then increasing of acidity will reduce the activity of catalyst. Ni-Cu/4Al and Ni-Cu/11Al deactivated in a very short time hence produced fewer amount of nanocarbon, while Ni-Cu/15Al was active in a very long period. The most effective catalyst is Ni-Cu/22Al, which produced the biggest amount of nanocarbon (4.15 g C/g catalyst). Ni catalyst diameter has significant effect on reaction performances mainly methane conversion and product yield. A small Ni crystal size gave a high methane conversion, a fast deactivation and a low carbon yield. Large Ni particle diameter yielded a slow decomposition and low methane conversion. The highest methane conversion was produced by catalyst diameter of 4 nm and maximum yield of carbon of 4.08 g C/ g catalyst was achieved by 15.5 nm diameter of Ni catalyst."

"Pengembangan dan penelitian suatu proses untuk mengurangi ketergantungan pada sumber fosil merupakan tema penting untuk memantapkan keberlangsungan sistem industri kimia di masa depan. Salah satu alternatif yang perlu dipertimbangkan adalah adanya berbagai bentuk sumber senyawa organik yang berasal dari material biomasa,k arena jenis material ini dapat terbaharui dari hasil fotosintesa melalui proses fiksasi karbon dioksida dan penangkapan energi matahari. Potensi material ini sangat prospektif sebagai sumber awal hidrokarbon baik sebagai bahan bakar maupun bahan kimia seperti LPG dan senyawa aromatik. Namun, rute proses melalui senyawa organik turunan biomasa menjadi hidrokarbon menggunakan proses katalitik dengan HZSM-5 sebagai katalis dengan memanfaatkan persenyawaan organik hasil fermentasi (aseton, butanol, alkohol) ataupun senyawa hasil pirolisis biomasa masih jarang dikembangkan. Sehingga apabila teknologi berbasis biomasa tersebut dapat berperan penting di masa mendatang, maka teknologi ini dapat memberikan kontribusi suatu sistem daur-ulang material yang lebih langgeng, mengurangi pengaruh beban pemanasan global akibat gas CO2. Serta dapat mencanangkan perubahan paradigma posisi minyak bumi sebagai sumber energi utama menjadi energi alternatif serta menjadikan aktivitas energy -hunting kearah energy -farming.

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The exploration and development of a promising process to reduce the dependency on fossil resources is an important issue for establishing a sustainable system of chemical industry in the future. An alternative option should be decided on the various form of biomass resources, because these materials are the results of botanical photosynthesis by fixation of carbon dioxide and solar energy in botanical activities as considered to be high potential usage as starting materials of resources. These kind of renewable resources are expected to be able to create many alternative routes for production of hydrocarbons for fuel and chemicals such as LPG (C3-C4hydrocarbons), aromatic chemicals hydrocarbons. However, a little attention has been given to the applications of HZSM -5 in efforts to find aromatic chemicals with utilization of hydrocarbons that come from the biomass -derived chemicals such as fermentation products (acetone, butanol), biomass - derived oil. If so, the biomass -based technology should play an important role for establishing a sustainable system of material recycle, free from CO2 global warming effect in the future. And the paradigm should be changed the position of petroleum oi l as main energy resource into the alternative energy resource."

"Bagas merupakan residu padat pada proses pengolahan tebu menjadi gula, yang sejauh ini masih belum banyak dimanfaatkan menjadi produk yang mempunyai nilai tambah (added value). Bagas yang termasuk biomassa mengandung lignoselulosa sangat dimungkinkan untuk dimanfaatkan menjadi sumber energi alternatif seperti bioetanol atau biogas. Dengan pemanfaatan sumber daya alam terbarukan dapat mengatasi krisis energi terutama sektor migas. Pada penelitian ini telah dilakukan konversi bagas menjadi etanol dengan menggunakan enzim xylanase. Perlakuan dengan enzim lainnya saat ini sedang dikerjakan di laboratorium kami mengingat hemisulosa juga mengandung polisakarida lainnya yang dapat didekomposisi oleh berbagai enzim. Hasil penelitian menunjukkan kandungan lignoselulosa pada bagas sebesar lebih kurang 52,7% selulosa, 20% hemiselulosa, dan 24,2% lignin. Hemiselulosa merupakan polisakarida yang dapat dihidrolisis oleh enzim xylanase dan kemudian akan difermentasikan oleh yeast S. cerevisiae menjadi etanol melalui proses Sakarifikasi dan Fermentasi Serentak (SSF). Beberapa parameter yang dianalisis pada penelitian ini antara lain kondisi pH (4, 4,5, dan 5), untuk meningkatkan kuantitas etanol dilakukan penambahan HCl berkonsentrasi rendah (0,5% dan 1% (v/v)) dan bagas dengan perlakuan jamur pelapuk putih (L. edodes) selama 4 minggu. Proses SSF dilakukan dengan waktu inkubasi selama 24, 48, 72, dan 96 jam. Perlakuan dengan pH 4, 4,5, dan 5 menghasilkan konsentrasi etanol tertinggi berturut-turut 2,357 g/L, 2,451 g/L, 2,709 g/L. Perlakuan penambahan HCl konsentrasi rendah mampu meningkatkan produksi etanol, penambahan dengan konsentrasi HCL 0,5 % dan 1 % berturut-turut menghasilkan etanol 2,967 g/L, 3,249 g/L. Perlakuan dengan menggunakan jamur pelapuk putih juga dapat meningkatkan produksi etanol yang dihasilkan. Setelah bagas diberi perlakuan L. edodes 4 minggu mampu menghasilkan etanol dengan hasil tertinggi 3,202 g/L.

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Utilization of Bagasse Cellulose for Ethanol Production through Simultaneous Saccharification and Fermentation by Xylanase. Bagasse is a solid residue from sugar cane process, which is not many use it for some product which have more added value. Bagasse, which is a lignosellulosic material, be able to be use for alternative energy resources like bioethanol or biogas. With renewable energy resources a crisis of energy in Republic of Indonesia could be solved, especially in oil and gas. This research has done the conversion of bagasse to bioethanol with xylanase enzyme. The result show that bagasse contains of 52,7% cellulose, 20% hemicelluloses, and 24,2% lignin. Xylanase enzyme and Saccharomyces cerevisiae was used to hydrolyse and fermentation in SSF process. Variation in this research use pH (4, 4,5, and 5), for increasing ethanol quantity, SSF process was done by added chloride acid (HCl) with concentration 0.5% and 1% (v/v) and also pre-treatment with white rot fungi such as Lentinus edodes (L.edodes) as long 4 weeks. The SSF process was done with 24, 48, 72, and 96 hour?s incubation time for fermentation. Variation of pH 4, 4,5, and 5 can produce ethanol with concentrations 2,357 g/L, 2,451 g/L, 2,709 g/L. The added chloride acid (HCl) with concentration 0.5% and 1% (v/v) and L. edodes can increase ethanol yield, The highest ethanol concentration with added chloride acid (HCl) concentration 0.5% and 1% consecutively is 2,967 g/L, 3,249 g/L. The highest ethanol concentration with pre-treatment by L. edodes is 3,202 g/L."