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"Pencemaran lingkungan akibat senyawa Bisfenol A (BPA) dari limbah plastik menjadi isu serius karena sifat toksiknya sebagai pengganggu endokrin. Untuk menanggulangi hal ini, dilakukan rekayasa silika mesopori berbasis biomassa tandan kosong kelapa sawit (TKKS) dengan surfaktan Pluronic P123 sebagai templating agent. Silika mesopori disintesis melalui proses sol-gel dengan variasi konsentrasi surfaktan P123, yaitu 5g, 10g, dan 15g. Karakterisasi material dilakukan dengan menggunakan teknik FTIR, SEM, BET, dan UV-Vis untuk menganalisis sifat fisik, morfologi, luas permukaan, dan kemampuan adsorpsi. Hasil penelitian menunjukkan bahwa variasi konsentrasi surfaktan P123 mempengaruhi struktur dan luas permukaan silika mesopori, dimana P123 10g menghasilkan luas permukaan terbesar (362,18 m2/g), volume pori optimal (0,47 cc/g), dan kapasitas adsorpsi BPA yang paling tinggi. Model kinetika adsorpsi BPA mengikuti model Pseudo-First Order, yang menunjukkan proses adsorpsi cepat pada awalnya dan melambat seiring waktu. Hasil ini menunjukkan bahwa silika mesopori berbasis TKKS dapat digunakan sebagai adsorben efektif untuk mengurangi kadar BPA dalam kemasan plastik.

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Environmental pollution caused by Bisphenol A (BPA) compounds from plastic waste has become a serious issue due to its toxic nature as an endocrine disruptor. To address this, mesoporous silica was engineered from oil palm empty fruit bunch (EFB) biomass using Pluronic P123 surfactant as a templating agent. Mesoporous silica was synthesized through the sol-gel process with varying concentrations of P123 surfactant, namely 5g, 10g, and 15g. Material characterization was performed using FTIR, SEM, BET, and UV-Vis techniques to analyze physical properties, morphology, surface area, and adsorption capacity. The results showed that varying the concentration of P123 surfactant influenced the structure and surface area of the mesoporous silica, with P123 10g yielding the largest surface area (362,18 m2/g), optimal pore volume (0.47 cc/g), and the highest BPA adsorption capacity. The BPA adsorption kinetics followed the Pseudo-First Order model, indicating a rapid adsorption process initially, which slowed down over time. These results demonstrate that EFB-based mesoporous silica can be used as an effective adsorbent to reduce BPA levels in plastic packaging. "

"Bisfenol A (BPA) merupakan senyawa kimia berbahaya yang tergolong Endocrine Disrupting Chemical (EDC), umum digunakan dalam industri plastik dan resin epoksi. Salah satu metode paling efektif untuk mengurangi risiko BPA adalah adsorpsi. Silika mesopori, yang biasanya disintesis dari prekursor sintetik seperti tetraethoxysilane (TEOS), memiliki kelemahan berupa biaya tinggi dan potensi dampak negatif terhadap kesehatan. Oleh karena itu, digunakan alternatif bahan baku berupa limbah biomassa sekam padi. Penelitian ini merekayasa silika mesopori dari sekam padi untuk mengevaluasi kapasitas dan efisiensi adsorpsinya terhadap BPA serta menentukan model kinetika adsorpsi yang sesuai. Sintesis dilakukan menggunakan NaOH 2,25 M dan HCl 2,25 M, dengan variasi penambahan surfaktan P123 (5, 10, dan 15 gram). Proses kalsinasi dilakukan pada suhu 500°C selama 6 jam. Analisis FTIR mengonfirmasi keberadaan gugus Si-O-Si, sementara analisis BET menunjukkan diameter pori 3,06 nm dan luas permukaan 373,963 m²/g pada penambahan 15 gram P123. Analisis SEM memperlihatkan morfologi yang semakin homogen pada penambahan 15 gram P123, didukung dengan hasil UV-Vis yang menunjukkan kapasitas adsorpsi dan %removal tertinggi sebesar 61,39 mg/g dan 61,39% jika dibandingkan dengan penambahan 5 dan 10 gram P123. Penelitian ini menunjukan bahwa model kinetika adsorpsi yang sesuai dengan proses adsorpsi Bisfenol A menggunakan silika mesopori ialah model Pseudo-First Order.

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Bisphenol A (BPA) is a hazardous chemical compound classified as an Endocrine Disrupting Chemical (EDC), commonly used in plastic and epoxy resin industries. One of the most effective methods to mitigate BPA exposure is adsorption. Mesoporous silica, typically synthesized from synthetic precursors such as tetraethoxysilane (TEOS), has drawbacks, including high costs and potential adverse health effects. Therefore, an alternative raw material derived from rice husk biomass waste was utilized. This study engineered mesoporous silica from rice husks to evaluate its adsorption capacity and efficiency for BPA and determine the appropriate adsorption kinetics model. The synthesis was conducted using 2.25 M NaOH and 2.25 M HCl, with the addition of P123 surfactant at varying amounts (5, 10, and 15 grams). Calcination was performed at 500°C for 6 hours. FTIR analysis confirmed the presence of Si-O-Si functional groups, while BET analysis revealed a pore diameter of 3.06 nm and a surface area of 373.963 m²/g with the addition of 15 grams of P123. SEM analysis demonstrated increasingly homogeneous morphology at 15 grams of P123, supported by UV-Vis results indicating the highest adsorption capacity (61.39 mg/g) and removal efficiency (61.39%) compared to 5 and 10 grams of P123. This study concludes that the adsorption kinetics of Bisphenol A using mesoporous silica follows the Pseudo-First Order model. "

"Limbah zat warna, khususnya zat warna Methylene Blue (MB) yang biasa digunakan dalam industri tekstil, menjadi permasalahan serius bagi lingkungan karena sifatnya yang sulit terurai dan toksik, merusak estetika dan keseimbangan ekosistem. Hal ini menyebabkan perlunya pengolahan pada limbah zat warna. Penelitian ini fokus pada kondisi optimum pengolahan limbah dengan cara adsorpsi menggunakan Silika Mesopori MCM-41 dan SBA-15 yang berasal dari limbah biomassa Tandan Kosong Kelapa Sawit (TKKS) sebagai adsorben zat warna alternatif yang efisien dan ekonomis. Silika mesopori dipilih karena struktur porinya yang mudah untuk dimodifikasi, dan memiliki kapasitas adsorpsi yang baik karena ukuran porinya. Proses sintesis dimulai dari preparasi SiO2 dari TKKS, diikuti oleh sintesis silika mesopori dengan metode sol-gel dan penggunaan CTAB untuk menghasilkan MCM-41 dan P123 sebagai template untuk menghasilkan SBA-15. Studi ini juga mengkaji kondisi optimum adsorpsi MB dengan variasi konsentrasi adsorbat, suhu, dan waktu, menggunakan metode Box-Behnken. Hasil penelitian ini menunjukkan bahwa TKKS dapat disintesis menjadi material berpori dan dapat digunakan sebagai adsorben metilen biru dengan kondisi optimum pada konsentrasi adsorbat 201,742 ppm, suhu 50°C, dan waktu 15,265 menit. Silika mesopori MCM-41 dan SBA-15 dapat digunakan pada 4 kali siklus pengulangan.

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Waste dye, particularly Methylene Blue (MB) commonly used in the textile industry, poses a serious environmental problem due to its non-biodegradable and toxic nature, harming aesthetics and ecosystem balance. This necessitates the treatment of dye waste. This study focuses on the optimum conditions for treating waste via adsorption using mesoporous silica MCM-41 and SBA-15 derived from oil palm empty fruit bunch (OPEFB) biomass waste as an efficient and economical alternative dye adsorbent. Mesoporous silica was chosen due to its easily modifiable pore structure and good adsorption capacity because of its pore size. The synthesis process began with the preparation of SiO2 from OPEFB, followed by the synthesis of mesoporous silica using the sol-gel method and CTAB to produce MCM-41, and P123 as a template to produce SBA-15. This study also examined the optimum conditions for MB adsorption with variations in adsorbate concentration, temperature, and time, using the Box-Behnken method. The results showed that OPEFB can be synthesized into a porous material and used as a methylene blue adsorbent under optimum conditions at an adsorbate concentration of 201.742 ppm, a temperature of 50°C, and a time of 15.265 minutes. Mesoporous silica MCM-41 and SBA-15 can be used for up to 4 cycles of reuse."

"Biomassa merupakan salah satu sumber energi alternatif yang berpotensi untuk dimaksimalkan di Indonesia. Sumber biomassa yang berpotensi salah satunya adalah kelapa sawit yang ketersediaannya melimpah dan limbah tandan kosongnya dapat diolah menjadi bio-oil. Namun produk bio-oil ini biasanya belum memiliki kualitas yang baik umumnya karena kandungan oksigenat yang tinggi sehingga belum bisa diaplikasikan secara luas.Tujuan penelitian ini adalah untuk menurunkan kadar senyawa oksigenat dalam bio-oil. Penelitian ini memakai temperatur operasi 550oC dengan lima perlakuan berbeda, yaitu tanpa melibatkan katalis, lalu menggunakan katalis ZSM-5 dengan dua ukuran kristal berbeda dan NiZSM-5 dengan dua ukuran kristal yang berbeda. Sintesis katalis ZSM-5 dilakukan dua kali dengan jumlah kadar air yang berbeda untuk mengontrol ukuran kristal yang didapatkan. Sintesis katalis ZSM-5 telah berhasil membentuk kristal alumina silika dengan ukuran partikel 3-5 μm pada sintesis pertama dan 150-250 nm pada sintesis kedua. Sementara impregnasi logam nikel kedalam katalis ZSM-5 dilakukan dengan metode wet impregnation menghasilkan loading logam nikel sebesar 9.88% paa sintesis pertama dan 10.96% pada sintesis kedua.Hasil sintesis bio-oil menunjukkan bahwa katalis mampu mereduksi kandungan senyawa oksigenat dan meningkatkan kandungan senyawa aromatik yang pada proses selanjutnya dapat dikonversi menjadi senyawa alkana atau digunakan sebagai bahan aditif. Secara berurutan, kandungan senyawa oksigenat dan aromatik pada bio-oil tanpa katalis, katalis ZSM-5 sintesis pertama, ZSM-5 sintesis kedua, NiZSM-5 sintesis pertama dan NiZSM-5 sintesis kedua adalah 53,01% dan 44.81%; 38,05% dan 45,02%; 37,57% dan 45,51%; 35,71& dan 48,28%; 35,07% dan 51,23%.

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Biomass is one of the alternative energy source that has a great potential to be developed. Biomass can come from many sources and one of the most potential to be utiliized is from empty fruit bunch of palm that can be synthesized to make bio-oil. There were several obstacles that inhibit the use of bio-oil, namely low heating value, high levels of acidity, corrosive, and unstable products. Those problem were due to the high content of oxygenate compounds in the bio-oil.

Purpose of the research is to obtain bio-oil product with less oxygenate compounds. This study uses fast pyrolysis method at 550oC, with five different treatments: production of bio-oil without catalyst, using ZSM-5 with two different crystal size, and using NiZSM-5 with two different crystal size. Synthesis of ZSM-5 has been carried out two times with different water ratio to reduce the crystal size.It has form alumina silica crystal with particle size around 3-5 μm at the first synthesis and 150-250 nm at the second. The impregnation of nickel metal to ZSM-5 has been carried out resulting nickel loading 9.88% at the first synthesis and 10.96% at the second.

The result of bio-oil shows that catalyst can reduce oxygenate compunds as well as increasing aromatic compound that later can be converted into alkane chain hydrocarbon-like petroleum diesel or used as additive compound. Respectively, oxygenates and aromatic content in bio-oil produced without catalyst, with ZSM-5 from first synthesis, with ZSM-5 from second synthesis, with NiZSM-5 from first synthesis dan with NiZSM-5 from second synthesis are 53.01% and 44.81%; 38.05% and 45.02%; 37.57% and 45.51%; 35.71% and 48.28%; and 35.07% and 51.23%."

"Currently the world’s second largest palm oil producer Malaysia produces a large amount of oil palm biomass each year. Although some oil palm parts and derivatives like empty fruit bunch and fibre have been commercialized as fuel, less attention has been given to oil palm fronds (OPF). Initial feasibility and characterization studies of OPF showed that it is highly feasible as fuel for gasification to produce high value gaseous fuel or syngas. This paper discusses the experimental gasification attempt carried out on OPF using a 50 kW lab scale downdraft gasifier and its results. The conducted study focused on the temperature distributions within the reactor and the characteristics of the dynamic temperature profile for each temperature zones during operation. An average pyrolysis zone temperature of 324oC and an average oxidation zone temperature of 796oC were obtained over a total gasification period of 74 minutes. A maximum oxidation zone temperature of 952oC was obtained at 486 lpm inlet air flow rate and 10 kg/hr feedstock consumption rate. Stable bluish flare was produced for more than 70% of the total gasification time. Similar temperature profile was obtained comparing the results from OPF gasification with that of woody biomass. Furthermore, the successful ignition of the syngas produced from OPF gasification ascertained that OPF indeed has a higher potential as gasification feedstock. Hence, more detailed studies need to be done for better understanding in exploiting the biomass as a high prospect alternative energy solution. In addition, a study of the effect of initial moisture content of OPF feedstock on the temperature distribution profile along the gasifier bed showed that initial moisture content of feedstock in the range of 15% gives a satisfactory result, while experiments with feedstock having higher moisture content resulted in lower zone temperature values."

"Produksi komoditas sawit terbesar di dunia. Proses pengolahan sawit menghasilkan limbah tandan kosong sawit (TKS) dengan kisaran 20-23 % dari berat tandan buah segar. TKS merupakan biomassa lignoselulosa, sehingga mengandung selulosa, hemiselulosa, dan lignin. Pemanfaatan selulosa dan hemiselulosa membutuhkan praperlakuan untuk membuka ikatan lignin yang menyelubungi keduanya. Pada penelitian ini, akan dilakukan praperlakuan tandan kosong sawit dengan metode amonium hidroksida berbantuan gelombang mikro. TKS diberi praperlakuan fisika dengan pencucian dan penggilingan hingga mencapai ukuran 30 mesh. Selanjutnya TKS dimasukkan ke dalam gelas kimia dan diberikan larutan amonium hidroksida dengan rasio padat-cair 1:10 dan konsentrasi yang divariasikan (7,5; 10; 12,5%). Campuran dimasukkan ke dalam microwave dengan variasi daya 280, 560, dan 840 W, serta variasi waktu 3, 6, dan 9 menit. Sampel dikarakterisasi dengan uji lignin Klason, SEM, dan XRD. Hasil yang diperoleh kemudian dioptimasi dengan metode Response Suface Methodology dengan pengaplikasian model Box-Behnken. Hasil mikrograf SEM menunjukkan perekahan dan pembentukan pori-pori pada mikrostruktur TKS. Hasil difraktogram XRD menunjukkan penurunan kristalinitas selulosa TKS sebesar 36,38%. Delignifikasi tertinggi diperoleh pada daya 840 Watt, konsentrasi 10%, dan waktu radiasi 9 menit, yaitu sebesar 63,32%. Hasil uji statistik dan model yang diperoleh menunjukkan efek linear pada faktor daya dan konsentrasi, sedangkan faktor waktu radiasi menunjukkan efek kuadratik. Titik optimum yang diperhitungkan terdapat pada daya 839,190 Watt, konsentrasi 12,427%, dan waktu radiasi 8,762 menit, dengan prediksi delignifikasi sebesar 79,514%.

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Indonesia is an agricultural country with the largest production of palm oil commodities in the world. The palm oil processing will produce oil palm empty fruit bunches (OPEFB) waste with a range of 20-23% of the weight of fresh fruit bunches. OPEFB is a lignocellulosic biomass, which contain cellulose, hemicellulose, and lignin. The use of cellulose and hemicellulose requires pretreatment to open the lignin bond that covers those materials. In this study, pretreatment of oil palm empty bunches using microwave-assisted ammonium hydroxide method will be carried out. The OPEFB was given a physical pretreatment by washing and grinding to reach a size of 30 mesh. After that, the OPEFB was put into a beaker and mixed with ammonium hydroxide solution with a solid-liquid ratio of 1: 10 under varied concentration (7.5; 10; 12.5%). The mixture was put into a microwave under power variation of 280, 560, and 840 W, with time variation of 3, 6, and 9 minutes. The samples were then characterized by Klason lignin, SEM, and XRD tests.

The results obtained were then optimized using Response Suface Methodology with the application of the Box-Behnken Model. The SEM micrograph showed openings and formation of pores in the OPEFB microstructure. The XRD diffractogram showed a 36.38% decrease in cellulose crystallinity. The highest delignification was obtained at power of 840 Watts, concentration of 10%, and time of 9 minutes, which was 63.32%. The statistical test and the model that was obtained showed a linear effect on power and concentration factors, while the radiation time factor showed a quadratic effect. The calculated optimum point was obtained at power of 837.190 Watts, concentration of 12.427%, and time of 8.762 minutes, with the predicted delignification of 79.514%."

"Penelitian berupa peningkatan kualitas bio-oil dengan bahan baku tandan kosong kelapa sawit merupakan sebuah kontribusi untuk merealisasikan pemanfaatan biooil sebagai bahan bakar alternatif. Hingga saat ini, terdapat beberapa kendala yang menghalangi penggunaan bio-oil di tengah masyarakat, yaitu rendahnya nilai heating value, tingginya tingkat keasaman, korosif, dan tidak stabilnya produk. Permasalahan tersebut bersumber dari tingginya kandungan senyawa oksigenat di dalam bio-oil. Penelitian ini bertujuan untuk mendapatkan bio-oil dengan kadar oksigenat yang lebih rendah. Dalam penelitian ini, digunakan metode fast pyrolysis pada temperatur 550o C, dengan empat perlakuan, yaitu produksi bio-oil tanpa katalis, dengan katalis RCC komersial, dengan katalis zeolit alam lampung teraktivasi, dan dengan katalis nanokristal ZSM-5 yang disintesis di laboratorium. Dari hasil sintesis katalis tidak terbentuk kristal SiO2, Al2O3, dan kristal mineral zeolit tertentu sehingga diperoleh beberapa evaluasi dari sintesis yang dijalankan. Produk bio-oil memiliki properti fisik dan kimia yang berbeda satu sama lain. Katalis zeolit terbukti mampu mereduksi senyawa oksigenat. Selain itu, katalis tersebut meningkatkan sejumlah kadar fenol yang mampu menaikkan nilai heating value. Secara berurutan, kandungan senyawa oksigenat dan fenol pada bio-oil tanpa katalis, dengan RCC komersial, dengan ZAL teraktivasi, dan dengan katalis sintesis adalah 42,48% dan 10,74%; 31,79% dan 29,1%; 33,26% dan 26,49%; serta 36,09% dan 22,94%. RCC komersial merupakan katalis yang memberikan produk bio-oil terbaik dengan penurunan senyawa oksigenat. Hal ini disebabkan karena kekuatan kristal yang lebih baik dibandingkan katalis zeolit alam teraktivasi dan katalis yang disintesis di laboratorium.

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Research in increasing quality of bio-oil with empty fruit bunch of palm as raw materials was a contribution to realize the utilization of bio-oil as an alternative fuel. There were several obstacles that inhibit the use of bio-oil, namely low heating value, high levels of acidity, corrosive, and unstable products. Those problem were due to the high content of oxygenate compounds in the bio-oil.

Purpose of the research is to get bio-oil product with less oxygenate compounds. This study uses methods of fast pyrolysis at 550o C, with four treatments: production of bio-oil without catalyst, with commercial RCC, with activated lampung zeolite catalyst, and with nanocrystal ZSM-5 catalyst synthesized in the laboratory.

Synthesis catalyst did not form crystal SiO2, Al2O3 and specific zeolite mineral, so it brings some evaluations. Bio-oil products have different physical and chemical properties. Zeolite catalyst can reduce oxygenate compounds. Besides, it is able to increase phenol quantity that makes effect for increasing of heating value.

Sequentially, oxygenates and phenol content in bio-oil produced without catalyst, with commercial RCC, with activated lampung zeolite catalyst, and with nanocrystal ZSM-5 catalyst synthesized are 42.48% and 10.74%; 31.79% and 29.1%; 33.26% and 26.49%; 36.09% and 22.94%. Commercial RCC gives best quality bio-oil with less oxygenates. It is caused by better crystalline strength compared with activated lampung zeolit catalyst and synthesized catalyst at laboratory."

"Biaya logistik secara signifikan dapat mempengaruhi harga TKKS sebagai bahan baku bioethanol generasi kedua, dimana bahan baku itu sendiri merupakan bagian terbesar komponen biaya operasional. Untuk itu diperlukan studi yang secara spesifik merancang rantai pasok biomassa serta mengkuantifikasi biaya transportasi. Pada penelitian ini, telah dikembangkan rancangan logistik untuk beberapa cluster yang masing-masing terdiri dari beberapa PKS (Pabrik Kelapa Sawit) untuk mensuplai pabrik bioethanol berkapasitas 50 kta di Provinsi Riau. Selanjutnya juga dilakukan kuantifikasi biaya logistik dengan mempertimbangkan jarak, jenis kendaraan, kondisi jalan, dan kondisi sumber TKKS. Biaya logistik terdiri dari harga TKKS (dari sumber), biaya transportasi dan biaya pra-perlakuan. Hasil penelitian ini, diharapkan mampu memberikan skema supply network yang optimal dan biaya yang layak dalam mendukung pengembangan bisnis bioethanol generasi kedua berbasis TKKS yang layak secara komersial. Skema tersebut adalah lokasi pabrik bioethanol harus berdekatan dengan pasokan bahan baku terbesar. Didapatkan 3 calon lokasi pabrik bioethanol berkapasitas 50kta di provinsi riau yang terletak di Kabupaten Pelalawan dan Indragiri hilir. Lokasi tersebut menghasilkan biaya transportasi terendah calon lokasi pabrik 2 sebesar Rp 156.000 dengan jarak ke terminal BBM sejauh 282 km dan yang termahal terletak di calon lokasi pabrik 1 yaitu dengan biaya transportasi sebesar Rp189.000 dengan jarak ke TBBM sebesar 120 km.

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Logistics costs can significantly affect the price of OPEFB as a second generation bioethanol raw material, where the raw material itself is the largest component of the operational costs. For this reason, studies are needed that specifically design biomass supply network and quantify transportation costs. In this study, we developed a design supply network for several clusters, each consisting of 15 PKS to supply a 50kta bioethanol plant in Riau Province. Furthermore, logistics cost quantification is also carried out by considering the distance, type of vehicle, road conditions, and conditions of the OPEFB source. Logistics costs consist of the OPEFB price (from source), transportation costs and pre-treatment costs. The results of this study are expected to be able to provide an optimal supply network scheme and a reasonable cost to support the development of a commercially viable second-generation bioethanol business based on EFB. The scheme is that the location of the bioethanol plant must be close to the largest supply of raw materials. There were 3 candidate locations for bioethanol factories with a capacity of 50kta in Riau province, which are located in Pelalawan and Indragiri downstream districts. This location generates the lowest transportation costs for prospective factory location 2 of Rp. 156,000 with a distance to the BBM terminal as far as 282 km and the most expensive is located in the prospective factory location 1, with a transportation cost of Rp.189,000 with a distance to TBBM of 120 km."

"Biomassa merupakan salah satu energi alternatif yang dapat mengatasi solusi krisis energi di Indonesia. Tujuan penelitian ini yaitu melihat pengaruh proses torefaksi terhadap sifat ketahanan moisture content, kemampuan reduksi ukuran biomassa dan ketahanan tekan pellet biomassa yang berasal dari bahan baku tandan kosong kelapa sawit. Analisa yang dilakukan untuk mengetahui karakteristik pengaruh torefaksi yaitu pengujian sifat ketahanan moisture content, pengujian kemampuan reduksi ukuran serta pengujian ketahanan tekan untuk melihat karakteristik sifat fisik pellet biomassa. Penelitian yang dilakukan yaitu membandingkan pembuatan pellet biomassa proses torefaksi pada variasi temperatur 225, 250, 275, 300 dan 325°C dengan tanpa proses torefaksi. Hasil penelitian menunjukkan sifat ketahanan moisture content terbesar pada kondisi temperatur 325°C dengan nilai 6,34 % penambahan moisture content, sedangkan yang terendah pada kondisi temperatur 225°C dengan nilai 32,08 % penambahan moisture content. Kemampuan reduksi ukuran tertinggi pada distribusi ukuran partikel < 125 μm yaitu pada kondisi non torefaksi sebanyak 5,89 gram, sedangkan yang terendah pada variasi temperatur 325°C sebanyak 2,18 gram. Untuk distribusi terbesar ukuran partikel > 297 μm yaitu pada kondisi temperatur 325°C sebanyak 2,81 gram, sedangkan distribusi terendah pada kondisi non torefaksi sebanyak 0,24 gram. Nilai ketahanan tekan pellet biomassa terbesar pada kondisi non torefaksi sebesar 2,44 kgf/mm2.

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Biomass is one of the alternative energy solutions that can overcome the energy crisis in Indonesia. The purpose of this study is to see the effect of the resistance properties torefaction moisture content, the ability to reduce the size and durability of biomass pellet press biomass feedstock derived from oil palm empty fruit bunches. Analysis is performed to determine the influence of the characteristics of the testing of resistance torefaction moisture content, test the ability to reduce the size and durability testing tap to see the characteristics of the physical properties of biomass pellets. Research carried out by comparing the biomass pellet making process torefaction the temperature variation 225, 250, 275, 300 and 325 °C with no torefaction process.

Results showed greatest resistance properties of moisture content on the conditions of temperature 325°C with the addition of the value of 6.34% moisture content, and the lowest at 225°C temperature conditions with a value addition of 32.08% moisture content. Ability to reduce the size of the highest in the distribution of particle size <125 μm is the condition of non torefacton much as 5.89 grams, while the lowest at 325°C temperature variations of as much as 2.18 grams. For the largest particle size distribution of >297 μm is 325°C rise in temperature as much as 2.81 grams, while the lowest distribution in non torefaction conditions as much as 0.24 grams. Resistance value of the largest biomass pellet press on condition of non torefaction of 2.44 kgf/mm2."

"Pembakaran batubara sebagai sumber energi fosil utama dunia menghasilkan produk samping berupa limbah fly ash. Produk samping ini termasuk ke dalam limbah berbahaya dan bersifat toksik. Jumlahnya yang melimpah dan terus bertambah dapat menimbulkan polusi bagi lingkungan sekitar. Dengan demikian, perlu dilakukan upaya pemanfaatan fly ash, salah satu caranya adalah sintesis silika mesopori sebagai media nutrient tanaman. Adanya kandungan silika (SiO2) sebesar 35 – 60 % dalam fly ash, sangat berpotensi dan sesuai untuk dimanfaatkan sebagai sumber silika dalam mensintesis silika mesopori. Pada penelitian ini, telah dilakukan sintesis silika mesopori yang berasal dari fly ash beserta pengaplikasiannya sebagai pupuk urea slow-release fertilizer (SRF). Silika mesopori yang dihasilkan kemudian dikarakterisasi dengan XRD, XRF, FTIR, SAA, dan UV-Vis. Hasil analisis XRD dan XRF pada pretreatment fly ash menunjukkan keberhasilan dalam proses penghilangan pengotor dengan indeks keberhasilan 82% dalam meningkatkan komposisi silika. Pada penelitian ini variasi paling optimum untuk menghasilkan material mesopori didapatkan oleh 2% CTAB yang dibuktikan dengan hasil analisis XRF dengan komposisi silikanya sebesar 97% dan dengan analisis SAA dengan SBET 1016 m2/g serta Sext 912 m2/g. Silika mesopori dengan 2% CTAB memiliki kemampuan swelling paling besar dengan ratio swelling 2.79 dibandingkan dengan variasi 1% CTAB dan 3% CTAB yang masing masing memiliki ratio swelling sebesar 2.27 dan 1.12.

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Coal combustion, the world's main fossil energy source, produces a by-product known as fly ash waste, which is classified as hazardous waste and toxic in nature. The abundance and proliferation of fly ash have polluted the environment. Therefore, it is necessary to optimize the utilization of fly ash in a variety of methods, one of which is use as a raw material for the synthesis of silica mesoporous as a plant nutrient medium. Around 35-60% of silica (SiO2) content, fly ash has emerged as a highly promising and suitabel source of silica for the synthesized of mesoporous silica. In this study, mesoporous silicas derived from fly ash were synthesized using sol-gel technique and applied as urea slow-release fertilizer. Silica mesoporous were then characterized using XRD, XRF, FTIR, SAA, and UV-Vis. The findings of XRD and XRF analysis on fly ash pretreatment indicated that 82% of impurities were successfully removed, therefore the silica composition was increased. In this research to obtain mesoporous material 2% CTAB achieved the best results, as evidenced by the XRF analysis with a silica composition of 97% and surface area of SBET 1016 m2/g and Sext 912 m2/g analyzed by SAA method. Mesoporous silica with 2% CTAB presented the best swelling ability with the ratio of 2.79, compared to 1% CTAB and 3% CTAB variations, which only showed swelling a ratio of 2.27 and 1.12, respectively."