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"Kopolimerisasi selulosa jerami padi dengan asam akrilat dan akrilamida menghasilkan superabsorben komposit. Selulosa diisolasi dari jerami padi dengan tahapan ekstraksi lipid dengan toluena: etanol (2:1). Penghilangan hemiselulosa dan lignin dengan menggunakan kalium hidroksida 5% dan hidrogen peroksida 2% pH basa suhu 90C. Rendemen selulosa yang diperoleh adalah 21,56% dengan Indeks kristalinitas 71,43%. Spektrum FTIR selulosa menunjukkan hilangnya serapan lignin pada 1728 cm-1. Kopolimerisasi berlangsung pada suhu 65C dengan dialiri gas nitrogen. Inisiator dan pengikat silang yang digunakan adalah kalium persulfat dan N?N-metilena bis akrilamida. Superbasorben yang dihasilkan menunjukkan kapasitas swelling air; larutan urea, kalium dihidrogen fosfat, ammonium klorida konsentrasi 100 ppm masing-masing adalah 895,48g/g ; 986,72g/g; 448,98g/g dan 387,11g/g. Superabsorben bersifat anionik yang dapat mengikat ammonium. Kinetika swelling memenuhi persamaan orde pseudo-kedua dan kinetika absorpsi memenuhi persamaan orde pseudo-kedua.

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Copolymerization of cellulose from rice straw with acrylic acid and acrylamide monomer produce composite superabsorbent. Cellulose was isolated from lipid content by extraction with toluene : ethanol (2:1). Hemicelluloses and lignin were removed by using 5% potassium hydroxide and 2% hydrogen peroxidoat alkaline pH at 90C. Cellulose yield obtained was 21.56% with 71.43% crystallinity index. FTIR spectra of lignin showed a loss of absorption at 1728 cm-1. Copolymerization was carried out at 65 C under nitrogen athmosphere. Initiator and cross linking agent used were potassium peroxodisulfate and N'N-methylene bis acrylamide. Superbasorben resulted from this experiment showed the water swelling capacity for the solution of 100 ppm of urea, potassium dihydrogen phosphate, ammonium chloride respectively 895.48 g / g, 986.72 g / g, 448.98 g / g and 387.11 g / g. Superabsorbent produced are anionic, that can bind ammonium cation. The kinetics of swelling dan absorption was following pseudo-second order equation."

"Biodegradation of rice straw was performed by solid state fermentation using two isolates penicillium to assess degradation time and effect of particle size on the growth and enzyme production. Biodegradation of the straw was conducted over 12 days using three straw particle size of 4, 8, and 12 mesh. The result showed that particle size effects the degradation process of rice straw. Delignification influence by activity of ligninase optimum size of 12 mesh with the degradation time in 2-4 days. Penicillium sp1 produced ligninase with the highest activity 1140 U/mL (lignin content 55.2%) and cellulase 140 U/m (content of cellulose 27.6%)., while highest ligninase and cellulase activity of penicillium sp2. 882 U/mL (lignin content 49.4%) and 102 U / mL (content of cellulose 15.9%). "

"Sebagian besar komoditas di bidang pertanian menghasilkan biomassa yang dapat dimanfaatkan sebagai sumber bahan baku industri petrokimia. Salah satu biomassa yang melimpah di Indonesia adalah jerami padi. Jerami mengandung lignoselulosa yang cukup tinggi sehingga bisa dimanfaatkan sebagai bahan dasar pembuatan asam adipat. Asam adipat merupakan bahan dasar petrokimia yang sering digunakan dalam pembuatan nilon-6,6.Tujuan dari penelitian ini adalah memproduksi asam adipat dari bahan dasar jerami dengan memvariasikan komposisi katalis yang digunakan. Metode penelitian yang digunakan adalah metode pirolisis dan catalytic cracking. Biomassa diberi pre-treatment berupa pengeringan dan pencacahan, kemudian dimasukkan ke dalam reaktor pirolisis.Berdasarkan hasil karakterisasi GC-MS, produk cair hasil pirolisis mengandung senyawa fenol(27,3%), siklopentena(14,34%), furan(15,48%), dan keton(10,01%). Sampel bio-oil diinjeksikan ke dalam reaktor katalitik dan akan bereaksi dengan katalis B2O3 dan Al2O3 membentuk senyawa asam adipat. Metode ini menghasilkan asam adipat dengan konsentrasi mencapai 33,72% dengan komposisi katalis yang terdiri dari 15% B2O3 dan 85% Al2O3.

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Most commodities in agriculture produce biomass that can be used as raw material for petrochemical industry. One of the biomass is abundant in Indonesia is rice straw. Straw contains lignocellulose high enough so that it can be used as a basis for making adipic acid. Adipic acid is a petrochemical base materials are often used in the manufacture of nylon-6,6.

The aim of this study was to optimize the production of adipic acid from straw based material by varying the catalyst used. The type and composition of the catalyst can affect the value of the conversion and yield of product, making it important to know the right combination in order to produce adipic acid with maximum yield. This research used pyrolysis dan catalytic cracking method to produce adipic acid. Biomass pretreatment given in the form of drying and size reduction, then inserted into the pyrolysis reactor.

Based on the results of GC-MS characterization, liquid products of pyrolysis contains phenolic compounds (27.3%), cyclopentene (14.34%), furan (15.48%), and ketones (10.01%). Bio-oil sample is injected into a catalytic reactor and reacts with B2O3 and Al2O3 catalyst to form adipic acid compounds. This method produces adipic acid with concentration reached 33.72% with 15% B2O3 and 85% Al2O3 catalyst composition."

"Hidrogen merupakan salah satu sumber energi alternatif yang menjanjikan sebab terdapat potensi proses produksi tanpa emisi. Skema produksi hidrogen dapat melalui proses termokimia, biokimia, ataupun elektrokimia. Metode termokimia memiliki konversi yang tinggi namun menghasilkan emisi yang cukup besar. Di sisi lain, proses biokimia tidak menghasilkan emisi yang tinggi akan tetapi biaya yang tinggi dan konversi yang rendah. Penelitian ini menganalisis aspek teknis, lingkungan, dan ekonomi dengan mengevaluasi yield gas hidrogen, emisi CO2, dan levelized cost of hydrogen (LCOH). Perhitungan emisi mencakup scope 1 & 2. Percobaan dark fermentation dilakukan pada suhu 85°C menggunakan bakteri thermotoga neapolitana dengan variasi konsentrasi inokulum (0,3-0,7 g/L) pada perangkat lunak SuperPro Designer. Variasi metode pretreatment juga dilakukan antara metode steam explosion dan hidrolisis asam. Percobaan gasifikasi dilakukan pada perangkat lunak Aspen Plus V11 dengan variasi rasio uap-biomassa (0,8-1,2) dan variasi suhu (750-950°C). Berdasarkan hasil penelitian ditemukan bahwa dalam konfigurasi proses dengan hasil hidrogen tertinggi, hasil yield gasifikasi lebih tinggi (0,71 m3/kg jerami padi) dibandingkan proses dark fermentation (0,067 m3/kg jerami padi). Sedangkan dalam hal emisi yang dihasilkan dark fermentation unggul secara signifikan yaitu hanya sebesar 501 kg CO2eq, dimana gasifikasi menghasilkan 1480 ton CO2eq. Secara harga pokok produksi metode gasifikasi memiliki harga yang lebih rendah sekitar 0,7 USD/m3 dibandingkan dark fermentation yang mencapai 2,98 USD/m3. Jadi, dalam segi yield dan LCOH metode gasifikasi lebih unggul daripada dark fermentation. Namun, dark fermentation lebih baik dari segi emisi dibandingkan gasifikasi.

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Hydrogen represents a promising alternative energy carrier due to its potential for emission-free production. Various production pathways are available, including thermochemical, biochemical, and electrochemical processes. Thermochemical methods generally offer high conversion efficiencies but are accompanied by substantial greenhouse gas emissions. In contrast, biochemical processes such as dark fermentation tend to generate lower emissions but are hindered by low conversion rates and high production costs. This study presents a comparative assessment of the technical, environmental, and economic aspects of hydrogen production via dark fermentation and gasification. Emission calculations cover scopes 1 & 2. The analysis focuses on hydrogen yield, carbon dioxide equivalent (CO₂eq) emissions, and levelized cost of hydrogen (LCOH). Dark fermentation was simulated at 85°C using Thermotoga neapolitana with varying inoculum concentrations (0.3–0.7 g/L) and different pretreatment methods, namely steam explosion and acid hydrolysis, using SuperPro Designer. Gasification was modeled in Aspen Plus V11 with variations in steam-to-biomass ratio (0.8–1.2) and operating temperature (750–950°C). Results indicate that gasification yielded significantly more hydrogen (0.71 m³/kg rice straw) compared to dark fermentation (0.067 m³/kg rice straw). However, dark fermentation resulted in considerably lower emissions (501 kg CO₂eq) relative to gasification (1480 tons CO₂eq). From an economic perspective, gasification also achieved a lower LCOH at approximately 0.7 USD/m³, compared to 2.98 USD/m³ for dark fermentation. Overall, while gasification demonstrates superior yield and economic performance, dark fermentation offers notable environmental benefits"