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"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."

"The use of waste cooking oil (WCO) as feedstock and in microwave heating technology helps to reduce the cost of biodiesel. In this study, a continuous flow transesterification of waste cooking oil (WCO) by microwave irradiation for biodiesel production using calcium oxide (CaO) as aheterogeneous catalyst, calcined from cockle shells, is used. The catalyst was packed inside a plastic perforated container mounted on a stirrer shaft and inserted inside the reactor. The thermocouple inside the reactor was connected to a temperature controller and microwave power input to maintain the temperature. Response surface methodology (RSM) was employed to study the relationships between power input, stirrer speed and liquid hourly space velocity (LHSV) on the WCO methyl ester (WCOME) conversion at a fixed molar ratio of methanol to oil of 9 and a reaction temperature set at 65oC. The experiments were developed using the Box-Behnken design (BBD) for optimum conditions. The transesterification of the WCO was produced at 72.5% maximum WCOME conversion at an optimum power input of 445 W, stirrer speed of 380 rpm and LHSV of 71.5 h-1 . The energy consumption in a steady state condition was 0.594 kWh for the production of 1 litre WCOME, for this heterogeneous catalyst is much faster than conventional heating."

"Pirfenidon yang dihantarkan secara peroral mengalami metabolisme lintas pertama, sehingga memerlukan dosis tinggi dan berpotensi menyebabkan efek samping sistemik. Oleh karena itu, pengembangan rute alternatif bagi pirfenidon perlu dilakukan. Penelitian sebelumnya melaporkan bahwa sistem penghantaran intrapulmonal berbasis solid lipid nanoparticles (SLN) dapat terdeposit dengan baik pada area alveolus paru-paru. Namun, karakteristik SLN dapat dipengaruhi oleh rasio lipid terhadap obat, jenis dan konsentrasi polimer. Oleh karena itu, optimisasi dengan metode permukaan respon perlu dilakukan untuk memperoleh formula SLN pirfenidon (P-SLN) yang optimal untuk penghantaran intrapulmonal. Lima belas formula disusun berdasarkan desain Box Behnken dengan tiga faktor yaitu, rasio lipid terhadap obat, jenis polimer dan konsentrasi polimer, serta tiga respon, meliputi ukuran partikel, PDI dan efisiensi penjerapan. Formula P-SLN optimal dikarakterisasi meliputi morfologi, kadar lembab, performa aerodinamik, studi disolusi dan stabilitas. Hasil optimisasi menunjukkan bahwa P-SLN optimal tersusun dari rasio lipid terhadap obat 6:1 dan 0,5% Plasdone K-29/32 (FO1). P-SLN FO1 memiliki bentuk sferis dengan ukuran partikel 212,67 nm, PDI 0,39, efisiensi penjerapan 95,02%, dan kadar lembab 1,59%. FO1 memiliki mass median aerodynamic diameter berkisar antara 0,54–12,12 μm. Selain itu, FO1 melepaskan pirfenidon sebanyak 89,61% dan 69,28% dalam medium pH 4,5 dan pH 7,4 selama 45 menit. Sebagai kesimpulan, FO1 terbukti memiliki karakteristik yang sesuai untuk menghantarkan pirfenidon melalui rute intrapulmonal.

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Orally administration of pirfenidone undergoes first-pass metabolism, hence requires high dose level and leads to systemic side effects. Therefore, it is necessary to develop an alternative route of administration for pirfenidone. Previous research reported that the solid lipid nanoparticle-based (SLN) intrapulmonary drug delivery system (IPDDS) was deposit well in the alveolar region of the lungs. However, the characteristics of SLN could be influenced by lipid-to-drug ratio, polymer type and concentration. Therefore, optimization using response surface methodology was carried out to obtain the optimized pirfenidon-loaded SLN (P-SLN) formula for IPDDS. Box-Behnken design was applied to create 15 formulas comprising three factors, including lipid-to-drug ratio, type and concentration of polymer and three responses, including particle size, PDI and entrapment efficiency. The optimized P-SLN formula was characterized, including morphology, moisture content, aerodynamic performance, dissolution and stability studies. The optimization results yielded an optimized P-SLN comprised a lipid-to-drug ratio of 6:1 and 0.5% Plasdone K-29/32 (FO1). The P-SLN FO1 had a spherical shape with a particle size of 212.67 nm, PDI of 0.39, entrapment efficiency of 95.02%, and moisture content of 1.59%. FO1 had a mass median aerodynamic diameter ranging from 0.54–12.12 μm. In addition, FO1 release 89.61% and 69.28% pirfenidone for 45 minutes in buffer medium pH 4.5 and pH 7.4. In conclusion, FO1 was proven to have an appropriate IPDDS characteristics for delivering pirfenidone."

"Turunan biomassa lignoselulosa dapat diubah menjadi bahan bakar dan berpotensi menjadi sumber bahan bakar alternatif. Asam levulinat (AL) telah diidentifikasi sebagai salah satu turunan biomassa yang bernilai tinggi karena sifatnya yang reaktif dan dapat dengan mudah dan ekonomis dihasilkan dari limbah lignoselulosa. AL dapat diubah menjadi gamma (γ)- valerolactone (GVL), salah satu bahan kimia yang penting dan prekursor untuk biofuel. Logam bimetalik NiFe diimpregnasi dengan persen loading logam sebesar 5% menggunakan metode impregnasi basah. Perbandingan berat Ni terhadap Fe yang diimpregnasi ditentukan dengan perhitungan kemometrik Box-Behnken Design (BBD) yaitu sebesar 1:4, 2.5:2.5 dan 4:1. Katalis NiFe/H-FDU-12 hasil sintesis dikarakterisasi menggunakan metode karakterisasi zat padat seperti FTIR, XRD, XRF, SAXS, SEM, dan BET SAA. Katalis kemudian diuji aktivitas katalitiknya dalam reaksi siklisasi hidrogenatif asam levulinat dengan metanol sebagai donor H+. Variasi perbandingan berat Ni:Fe, suhu, dan waktu reaksi dilakukan sesuai dengan desain eksperimen BBD untuk penentuan kondisi optimum. Hasil reaksi uji aktivitas katalitik untuk konversi asam levulinat (AL) menjadi gamma-valerolactone (GVL) dengan yield GVL tertinggi sebesar 87.52% dihasilkan menggunakan katalis Ni1Fe4/H-FDU-12 dengan suhu reaksi 180 C selama 2 jam. Metode Box-Behnken digunakan untuk melihat pengaruh variasi perbandingan berat Ni:Fe, suhu, dan waktu terhadap reaksi konversi AL menjadi GVL. Dengan model koefisien linear, ditentukanlah bahwa suhu memiliki pengaruh terbesar dibandingkan faktor lainnya. Dengan mengoptimalkan faktor dalam rentang masing-masing, konversi AL sekitar 98.83%, yield GVL 77.17% dan selektivitas 81.95% dicapai pada kondisi spesifik: ratio Ni:Fe 1:4, suhu reaksi 180 °C, waktu reaksi 3 jam.

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Lignocellulosic biomass derivatives can be converted into fuel and have the potential to become alternative fuel sources. Levulinic acid (LA) has been identified as one of the high value biomass derivatives due to its reactive nature and can be easily and economically produced from lignocellulosic waste. LA can be converted into gamma (γ)-valerolactone (GVL), an important chemical and a precursor for biofuel. The bimetallic NiFe metal was impregnated with a metal loading percentage of 5% using wet impregnation method. The weight ratio of Ni to Fe impregnation was determined using Box-Behnken Design (BBD) chemometric calculations, resulting in ratios of 1:4, 2.5:2.5, and 4:1. The synthesized NiFe/HFDU- 12 catalysts were characterized using solid-state characterization methods such as FTIR, XRD, XRF, SAXS, SEM, and BET SAA. The catalyst was then tested for its catalytic activity in the hydrogenative cyclization reaction of levulinic acid with methanol as the H+ donor. Variations in the Ni:Fe weight ratio, temperature, and reaction time were conducted according to the BBD experimental design to determine the optimum condition. The results of the catalytic activity test showed that the highest yield of gamma-valerolactone (GVL), reaching 87.52%, was obtained using the Ni1Fe4/H-FDU-12 catalyst at a reaction temperature of 180 °C for 2 hours. The Box-Behnken method was used to assess the influence of variations in the Ni:Fe weight ratio, temperature, and reaction time on the conversion of LA to GVL. Through the linear coefficient model, it was determined that temperature had the greatest influence compared to other factors. By optimizing the factors within their respective ranges, a conversion of approximately 98.83% for LA, a GVL yield of 77.17%, and a selectivity of 81.95% were achieved under specific conditions: Ni:Fe ratio of 1:4, reaction temperature of 180°C, and reaction time of 3 hours."

"Optimasi adalah disiplin ilmu yang digunakan untuk mencari nilai optimal dalam suatu fungsi. Ilmu ini banyak digunakan untuk mengurangi biaya dan waktu dalam meneliti suatu eksperimen agar diperoleh hasil yang terbaik. Penelitian ini bertujuan untuk memperoleh kondisi proses optimal untuk memaksimalkan luas permukaan dan yield. Bahan baku yang digunakan adalah ampas kopi, tempurung kelapa, dan polyethylene terephthalate (PET). Metode aktivasi yang digunakan adalah aktivasi fisika-kimia dengan senyawa aktivasi KOH, NaOH, H3PO4, dan K2CO3. Penentuan kondisi optimal dilakukan dengan metode respons permukaan (RSM) tipe Box-Behnken Design (BBD). Model yang diperoleh dianalisis menggunakan uji ANOVA dan uji residual. Hasil RSM berupa plot kontur dan permukaan yang digunakan untuk megetahui wilayah kondisi optimum serta analisa pengaruh faktor terhadap respons. Nilai kondisi optimum ditentukan menggunakan Response Optimizer dan diperoleh hasil bahwa sintesis karbon aktif dari ampas kopi dengan senyawa KOH, NaOH, H3PO4, dan K2CO3 terjadi ketika rasio impregnasi 1,00-1,37, suhu aktivasi 600-800°C, dan waktu aktivasi 60-120 menit. Sintesis optimal dari tempurung kelapa terjadi ketika rasio impregnasi 1,00-3,00, suhu aktivasi 647-808°C, dan waktu aktivasi 70-120 menit. Sintesis optimal dari PET terjadi ketika rasio impregnasi 1,00-2,80, suhu aktivasi 700-800°C, dan waktu aktivasi 109-120 menit.

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Optimization is a discipline to obtain the best value of a function. This study is used to minimize research cost and time. This research is done to achieve the optimum condition of process conditions for maximum surface area and yield of activated carbon. The precursors used in this research are waste coffee, coconut shell, and polyethylene terephthalate (PET). The type of activation method used is physical-chemical activation with KOH, NaOH, H3PO4, and K2CO3 as activating agents. To determine the optimum condition, this research use Response Surface Method (RSM) with Box-Behnken Design (BBD). The resulting model is tested using ANOVA analysis and the residual test. When the model passes the test, plot contours and surfaces achieved can be analyzed to determine the optimum area and the behavior of factors and responses. Response Optimizer option is used to determine the optimum value. Results show that synthesis of activated carbon using waste coffee and activating agents KOH, NaOH, H3PO4, and K2CO3 are optimized when impregnation ratio is 1.00-1.37, temperature is 600-800°C, and activation time 60-120 minutes. Synthesis from coconut shell is optimized when impregnation ratio is 1.00-3.00, temperature is 647-808°C, and activation time 70-120 minutes. Synthesis from PET is optimized when impregnation ratio is 1.00-2.80, temperature is 700-800°C, and activation time 109-120 minutes."