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"Diafiltration by means of the ultrafiltration system of probiotic fermented Mung beans (Phaseolus radiatus L.) concentrate has been performed to reduce or eliminate salts and smaller impurities than the nominal cut-off of the membrane of 20,000 nominal weight cut-off (NWCO). These processes have been conducted as an attempt in order to get a probiotic product with organoleptic acceptability, composition, and the optimal total lactic acid bacteria (LAB)counts because the presence of salts will affect on the viabilityof LAB and the cell lysis of LAB and limit its utility in food products. Concentrate of probiotic mung beans was prepared through fermentation of LAB using inoculum of LAB consisting ofLactobacillus bulgaricus and Streptococcus thermophylus(1 : 1) on fermented mung beans extract inoculated by inoculum ofRhizopus ?C1in rice substrates at salt condition. Ultrafiltration and diafiltration modes have been carried out at flow rate of 8.77 Liter/minute, room temperature and the pressure of 5 bar (0 to 79.7 minutes) and 7 bar (0-154.5 minutes) with the ratio of the volume of pure water to the volume of initial feed (number of diavolume, Nd)of 0, 0.25, 0.5, 0.75, 1.0 and 1.25, respectively. The experiment results based on total LAB counts as a probiotic product show that a high Nd can reduce the salt content but increase the total LAB counts. Nd of 1.0 results reduce the salt content which is equal to retentate, permeate, and the optimal total LAB counts. Ultrafiltration and diafiltration modes at the pressure of 7 bar and Nd of 1.0 give a retentate with total solid of 6.1355%, salt of 1.3515% and remove 86.15% of the salt from probiotic fermented mung beans concentrate and total LAB counts of 10.73 log cycles. Meanwhile, the permeate obtained at this condition results in flux value of 10.83 Liter/m 2.hour with contents of total solid of 6.8199%, salt of 1.325% and total LAB counts of 5.49 log cycles."

"Sintesis nanozeolit telah dilakukan dengan teknik seeding, dimana seed merupakan zeolit Y dengan tetraetilortosilikat (TEOS) sebagai sumber silika dan aluminium isopropoksida Al[((CH3)2CHO)]3 sebagai sumber aluminium dan tetrametilammonium hidroksida (TMAOH) sebagai molekul pengarah struktur. Proses kristalisasi dilakukan dengan teknik refluks pada suhu 100oC selama 192 jam. Kondisi optimum untuk pertumbuhan kristal zeolit adalah pada pH 9 dengan lama pertumbuhan kristal FAU selama 18 jam pada suhu 100oC dengan volume seed 10 mL dalam 20 mL larutan koloid FAU. Nanozeolit hasil sintesis dikarakterisasi menggunakan XRD, SEM-EDS, FTIR dan BET. Pola XRD menunjukkan nanozeolit memiliki struktur zeolit Y, yang diperkuat dengan rasio Si/Al sebesar 1,84 dari karakterisasi dengan EDS. Pencitraan dengan SEM menunjukkan bahwa kristal zeolit tumbuh saling bertumpuk membentuk agregat dengan ukuran 2 µm. Analisis dengan metode BET menunjukkan luas permukaan spesifik zeolit, diameter pori rata-rata dan volume pori berturut-turut adalah 521,682 m2/g, 10,667 Å, dan 0,2783 cc/g. Untuk pemisahan gas, telah dilakukan sintesis membran nanozeolit pada suatu kasa baja stainless dengan teknik redispersi. Membran selanjutnya diuji untuk aplikasi pemisahan gas metanol-etanol sebagai gas model dan dideteksi menggunakan GC-FID. Pengamatan awal menunjukkan bahwa gas etanol dapat tertahan oleh membran.

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AbstractNanozeolit synthesis was conducted by seeding method, in which the seed is a zeolite Y with tetraethyil orthosilicate (TEOS) as silica source and aluminium isopropoxide Al[((CH3)2CHO)]3 as a source of aluminum and tetramethylammonium hydroxide (TMAOH) as the structure directing agent. Crystallization process carried out by using reflux at a temperature of 100oC for 192 hours. The optimum conditions for crystal growth of zeolite crystals at pH 9 with FAU-term growth for 18 hours at a temperature of 100oC with seed volume 10 mL in 20 mL of colloid solution FAU. Nanozeolite synthesis products were characterized using XRD, SEM-EDS, FTIR and BET. XRD pattern shows nanozeolite has the structure of zeolite Y, which is reinforced with Si/Al ratio of 1.84 from the characterization by EDS. SEM imaging showed that the zeolite crystals grow over one another to form aggregates with a size of 2 µm. The analysis by the BET method shows specific surface area of zeolite, average pore diameter and pore volume are 521.682 m2/g, 10.667 Å and 0.2783 cc/g, respectively. For gas separation, synthesis membrane of nanozeolite has been done in a stainless steel mesh by redispersion method. Membranes were then tested for gas separation applications of methanol-ethanol as a gas model and detected using GC-FID. Initial observations indicate that ethanol gas can be restrained by the membrane. "

"Penelitian ini bertujuan untuk mengambil kembali logam kobalt dari limbah Lithium Ion Battery (LIB) atau baterai Li-Ion karena pada tahun 2000 kadar mencapai 200-500 ton/tahun dimana kobalt terdapat 30% yang dapat membahayakan lingkungan. Teknologi membran cair emulsi adalah salah satu teknologi rekoveri logam yang sangai baik karena sangat selektif, dapat diaplikasikan dalam skala besar, dan hemat waktu. Tahap awal diperlukan proses leaching menggunakan asam sitrat dengan konsentrasi 1 M menghasilkan kobalt 89,74% dan lithium 46,80% pada suhu 55oC selama 50 menit. Tahap ekstraksi dengan membran cair emulsi dengan ekstraktan (Cyanex 272) konsentrasi 0,05 M dan kadar surfaktan (Span-80) 6% karena angka tersebut menghasilkan emulsi paling stabil. Ekstraksi dilakukan pada suhu ruang dan pengadukan 250 rpm dan menghasilkan ekstraksi 48,73% Co dan 13,06% Li pada pH 5,5. Penelitian ini cukup selektif untuk memisahkan logam Co dan Li.

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This research has a purpose to recapture cobalt metal from spent Lithium Ion Battery (LIB) or Li-Ion battery because in 2000 the amount of the waste was 200-500 ton/year which contained 30% cobalt that can harm the environment. Emulsion liquid membrane technology is one of the most best technology in metal recovering because highly selective recovery techniques, can be applied on a large scale, and time saving. The initial stage is leaching process is required to use citric acid at a concentration of 1 M to produce cobalt 89,74% and lithium 46,80% at 55oC for 50 minutes. Then, phase extraction with liquid membrane emulsion with the extractant (Cyanex 272) 0,05 M concentrations and levels of surfactants (Span-80) 6% as the figure most stable emulsions in this research. The extraction is done at room temperature and stirring 250 rpm and generates extraction of 48,73% Co and 13,06% Li at pH 5.5. This study was selective enough to separate the metals Co and Li."

"Penelitian ini menginvestigasi pengaruh modifikasi Polyether Polyurethane Dispersion (PUD) terhadap sifat-sifat membran bitumen untuk aplikasi waterproofing di iklim tropis. Bitumen dasar dimodifikasi dengan PUD pada konsentrasi 5%, 10%, dan 15% melalui metode pencampuran panas (hot mix) pada 160°C. Karakterisasi material mencakup analisis sifat mekanik (penetrasi dan daktilitas), termal (TGA), hidrofobisitas (sessile drop), dan morfologi (mikroskop optik). Hasil menunjukkan bahwa penambahan PUD secara signifikan meningkatkan kelembutan (penetrasi) dan hidrofobisitas permukaan bitumen. Namun, terjadi penurunan daktilitas yang drastis pada konsentrasi di atas 5%. Analisis morfologi mengonfirmasi bahwa penurunan ini berkorelasi kuat dengan meningkatnya aglomerasi aspalten. Secara termal, bitumen termodifikasi menunjukkan stabilitas awal yang sedikit lebih baik. Dengan mempertimbangkan keseimbangan antara peningkatan hidrofobisitas dan penurunan sifat mekanik, konsentrasi 5% PUD diidentifikasi sebagai rasio modifikasi yang paling optimum.

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This study investigates the effect of Polyether Polyurethane Dispersion (PUD) modification on the properties of bitumen membranes for waterproofing applications in tropical climates. The base bitumen was modified with PUD at concentrations of 5%, 10%, and 15% via a hot mix method at 160°C. Material characterization included the analysis of mechanical properties (penetration and ductility), thermal behavior (TGA), hydrophobicity (sessile drop), and morphology (optical microscopy). The results indicate that the addition of PUD significantly increased the material's softness (penetration) and surface hydrophobicity. However, a drastic decrease in ductility was observed at concentrations above 5%. Morphological analysis confirmed that this decline strongly correlated with increased asphaltene agglomeration. Thermally, the modified bitumen exhibited slightly better initial stability. Considering the trade-off between enhanced hydrophobicity and diminished mechanical properties, a 5% PUD concentration was identified as the optimal modification ratio.

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"Gas N2O merupakan salah satu senyawa dari NOx. Senyawa ini satu dari beberapa gas yang dapat menyebabkan gas rumah kaca. Meskipun konsentrasi N2O sedikit diudara tetapi sangat sulit terdekomposisi diudara. Oleh karena itu diperlukan adanya pemisahan NOx dalam bentuk N2O. Kini telah dikembangkan teknologi membran dengan kontaktor serat berongga yang dapat mengatasi permasalahan pencemaran udara. Prinsip dari kontaktor membran ini menggunakan gaya penggerak berupa perbedaan konsentrasi. Pengaruh konsentrasi pelarut merupakan salah satu parameter dalam absorpsi NOx oleh karena itu penelitian ini menguji pengaruh konsentrasi pelarut larutan HNO3 dalam kinerja penyerapan gas NOx melalui kontaktor membran serat berongga superhidrofobik. Dari penelitian ini dilakukan uji perpindahan masa serta untuk analisis gas dilakukan dengan Gas Chromatography. Gas Chormatography digunakan untuk menganalisis kandungan gas NOx yang terserap setelah percobaan. Variabel bebas dari penelitian ini yaitu konsentrasi pelarut HNO3 sebesar 0,5; 1; 1,5; 2M dan serat membran yaitu 2000, 4000, 6000 sedangkan variabel tetap yaitu laju alir gas 0,1 L/menit ,dan konsentrasi H2O2 0,5 wt. Pada penelitian ini didapatkan persen penyerapan N2O, koefisien perpindahan massa fluks perpindahan massa, N2O loading terbesar secara berturut ndash; turut yaitu 89,6 , 4,95x10-6 m/s, 10,2x10-5 mol/m2s, 4,43 x10-2 mol N2O/mol pelarut. Semakin besar laju alir maka semakin besar penurunan tekanan dalam penelitian ini rasio penurunan tekanan berkisar antara 1, 107- 2,04. Kata kunci: absorpsi N2O, hollow fiber contactor membrane, jumlah serat, konsentrasi HNO3, superhidrofobik.

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Dinitrogen oxide is one of compound NOx. N2O one of compound NOx which can to make effect global warming. Although concentration N20 is small in the atmosfer but N2O can rsquo t decomposed in air but solute in water. Therefore, we need separation N2O as NOx. Nowdays membran technology have been developed by people to overcome problem in air pollution. The main principle of membrane contactor use gradient concentration as a driving force. In this study to knowing influence concentrations of solvent HNO3 in absorp gas NOx through superhidrophobic hollow fiber membrane contactor. Gas Chromatography is used to analyse concentration gas NOx in sample after research. Independent variable in this study is concentration of HNO3 0,5 1 1.5 2 M and numerous of fibers 2000,4000,6000 meanwhile dependent variable are flow rates gas 0,1 L minute, and concentration of H2O2 0,5 wt. This study aims to see the effects of concentrations of HNO3 and number of fibers in the contactor on the mass transfer coefficient KL , efficiency of absorption R , flukx J , and NOx loading. In this study, the largest percentage of N2O absorption, coefficient of mass transfer, flukx of mass transfer, N2O loading are 89,6 , 4,95x10 6 m s, 10,2x10 5 mol m2s, 4,43 x10 2 moles of N2O mol of solvent. Increasing flow rate will be obtained pressure drop rise. In this research the ratio of pressure drops ranges from 1, 107 2.04. Key Words absorption N2O, amount of fiber, concentration of HNO3, hollow fiber contactor membrane, superhidrophobic "

" ABSTRAKp.p1 margin: 0.0px 0.0px 0.0px 0.0px; font: 11.5px Times New Roman Kebutuhan akan energi bersih dan berkelanjutan meningkat semenjak dunia mengakui bahwa perubahan iklim yang disebabkan oleh emisi karbon-antropogenik merupakan masalah yang serius. Bahan bakar minyak berbasis etanol yang terbuat dari tebu dan jagung digunakan sebagai sumber energi berkelanjutan. Kendati produksi etanol yang umum, yaitu dengan metode distilasi, sudah mencapai pada tahap kematangannya, proses tersebut masih mengonsumsi energi yang tinggi. Hal tersebut membuat peneliti mencari opsi baru untuk proses produksi tersebut. Membran Forward Osmosis FO , membran separasi yang umum digunakan dalam riset untuk memisahkan campuran berbasis air, diusulkan untuk memisahkan campuran berbasis etanol. Namun, tingkat riset yang telah dilakukan untuk separasi etanol masih minim dan belum dapat diimplementasikan pada skala industri yang bersifat kontinu. Model matematika yang berasal dari hasil laboratorium kemudian dibentuk untuk merancang proses dari berbagai parameter berskala industri. Model tersebut kemudian diimplementasikan pada program simulasi Aspen-Plus. Berdasarkan hasil simulasi percobaan, membran komersil Cellulose Triacetate CTA dinyatakan tidak layak untuk digunakan karena tinggi nya jumlah etanol yang terbuang. Maka dari itu, beberapa parameter membran telah dimanipulasi untuk menghasilkan membran teoritis untuk digunakan dalma perancangan proses beriorientasi FO secara umum, menganalisa perbandingan secara ekonomi dengan proses distilasi, dan menentukan target riset untuk parameter optimum pada membran di masa depan.

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ABSTRACTp.p1 margin 0.0px 0.0px 0.0px 0.0px font 11.5px Times New Roman Demand for sustainable and clean energy carriers had increased since the world acknowledged climate change caused by anthropogenic carbon emissions as a serious issue. Fuel grade ethanol made from sugarcane or corn is a biofuel that has been placed as one renewable energy source. Despite the maturity of the ethanol production process, it is energy intensive and researchers are always looking for new options. Forward Osmosis FO is a membrane based separation technique that is popular in many water mixture research papers, which recently proposed for ethanol production. However, these papers have only looked at membrane materials and minimal research exists into the feasibility of incorporating FO technology into continuous production. Working from a laboratory scale data in FO research paper, mathematical models could be constructed to design certain parameters for industrial scale FO. These were implemented in Aspen Plus simulation. Commercial Cellulose Triacetate CTA membranes were concluded to be not feasible due to the comparatively low ethanol rejection, which leads to high losses. Nonetheless, building on these results, certain parameters were manipulated to produce theoretical membranes, which help to visualize FO oriented process design, an economical comparison analysis with the current distillation technology and research targets for membrane performance properties. "