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Environmental Impacts Evaluation of Sorbitol Production from Glucose
Get PDFA life cycle assessment (LCA) has been performed on sorbitol production from glucose, which aims to quantify and evaluate the environmental impacts that produced from the process. SuperPro Designer software was employed to perform the process simulation, while SimaPro was used to quantify the LCA.Potency of global warming, acidification, eutrophication, photochemical oxidants creation, abiotic depletion, and ozone layer depletion were evaluated. A gate-to-gate LCA study of sorbitol production showed that global warming potential (GWP) had the largest impact to environment with the value of 3.551 kg CO2 eq/kg sorbitol. Glucose and electricity consumption were known as two major contributors to GWP, and hydrogen reactor was the main consumer of electricity. The use of glucose were responsible for more than 50% of total environmentalimpact in each category. Performing heat integration in sorbitol processing is highly recommended for gate-togate system to reduce energy demand, thus decreasing the environmental impacts. Therefore, this LCA study may be applied to perform a sustainable improvement on sorbitol production process.Keywords: sorbitol; life cycle assessment; global warming potentia
Pelindian Neodymium dari Magnetik Coal Fly Ash menggunakan Asam Asetat sebagai Pelarut
Get PDFNeodymium (Nd) has been known as a vital component in the modern industry such as for very strong permanent magnets (NdFeB magnet). Some countries are starting to look for alternative sources of Nd such as coal fly ash (CFA), which is the waste from coal combustion. This study aims to look at the potential for Nd extraction from CFA using acetic acid at atmospheric pressure. The effect of CH3COOH concentrations (0,1-1,0 N), and leaching temperature (26-60 oC) was investigated. The experiment was carried out under a constant agitation speed (400 rpm), S/L ratio (3,75 % (W/V)) and CFA particle size (-400 mesh). The highest leaching eficiencies (72%) were achieved for concentration of acetic acid 0,5 N at 60 oC. The leaching kinetics results showed that it best fits the shrinking core model: [t.kap=1-3(1-XB) 2/3 +2(1-XB)] ensuring the overall leaching process is controlled by difussion ash layer. The activation energy determined from the experimental study was of 15,38 kJ/mol.ABSTRAK: Neodymium (Nd) telah dikenal sebagai komponen penting dalam industri modern diantaranya sebagai magnet permanen (magnet NdFeB). Beberapa negara kini mulai mencari sumber alternatif Nd yang salah satunya adalah abu terbang batubara, yang merupakan hasil dari pembakaran batubara sebagai sumber energi listrik. Penelitian ini bertujuan untuk mempelajari pelindian Nd dari abu terbang batubara menggunakan asam asetat sebagai pelarut pada kondisi atmosferik. Pada penelitian ini dipelajari pengaruh konsentrasi asam asetat (0,1-1,0 N) dan pengaruh suhu pelindian (26-60 oC). Beberapa kondisi percobaan yang dijaga tetap yaitu kecepatan pengadukan (400 rpm), rasio S/L (3,75 % W/V) dan ukuran partikel (-400 mesh). Hasil pelindian tertinggi (72 %) diperoleh pada konsentrasi asam asetat 0,5 N pada 60 oC. Hasil percobaan menunjukkan pelindian Nd dari magnetik CFA menggunakan asam asetat mengikuti model shringking core yang dikontrol oleh difusi lapisan abu: [t.kap=1-3(1-XB)2/3 +2(1-XB)], dengan energi aktivasi sebesar 15,38 kJ/mol
Pembuatan Biodisel dari Ampas Kelapa dengan Metode Transesterifikasi In-Situ dan Katalis Kalsium Oksida
Get PDFBiodiesel is an alternative fuel for diesel engine that attracts the world attention. Indonesia is one of the biggest coconut producers in the world. Coconut meat waste is known to still contain up to 24% wt of vegetable oil. The potential of this coconut waste can be used for producing biodiesel that has economical value. This research uses coconut waste as the main raw material. The biodiesel production process is carried out by in-situ transesterification method with methanol as the solvent and reactant; and calcium oxide powder as the catalyst. The catalyst is activated by stirring and heating in methanol. The oil percentage in the coconut waste obtained from soxhletation is 20 % wt. The ratio of methanol to coconut waste of 12.5:1 (v/w) and catalyst to coconut waste of 3.5 % wt results the biodiesel yield of 96.43 % mol. The biodiesel flash point at this variable is 116 °C. This value has met the Badan Standar Nasional (BSN) standardBiodisel adalah bahan bakar alternatif untuk mesin disel yang mendapat perhatian besar dunia. Indonesia merupakan salah satu negara penghasil kelapa terbesar di dunia. Ampas daging kelapa masih mengandung minyak nabati sampai 24% berat. Potensi dari ampas kelapa tersebut dapat dimanfaatkan untuk memproduksi biodiesel yang ekonomis. Penelitian ini menggunakan ampas kelapa sebagai bahan baku utama. Proses produksi biodiesel dilakukan dengan transesterifikasi in-situ menggunakan metanol sebagai pelarut dan reaktan dan serbuk kalsium oksida sebagai katalis. Katalis diaktivasi dengan pengadukan dan pemanasan dalam metanol. Kadar minyak dalam ampas kelapa yang diperoleh melalui sokletasi sebesar 20% berat. Perbandingan metanol terhadap ampas kelapa 12.5:1 (v/b) dan perbandingan katalis terhadap ampas kelapa 3.5% (b/b) menghasilkan yield biodisel sebesar 96.43% (mol/mol). Titik nyala biodisel pada variable tersebut mencapai 116oC. Nilai tersebut telah memenuhi standar dari Badan Standar Nasional (BSN)
Aplikasi Tuning Metode Cohen-Coon pada Pengendali pH di Tangki Neutralisasi, Unit Pengolahan Limbah
Get PDFWastewater generated in industry should be treated, in order to meet the standards set by the Government. pH became important parameters in the process of wastewater treatment. One of waste in industrial synthetic fibers contain ions that make pH of wastewater ranged from 2 to 3. The value of the threshold for the pH of the wastewater, based on regulation of the Minister of environment, ranged from 6 to 9. The main process to achieve this standar was the neutralization process. In order to fulfilment the pH target, pH controller has been used to monitor the pH at neutralization tank. pH controller which is used is a type of PID (proportional, integral, derivative) controller. The PID parameter that used in the controller are proportional gain (Kc) 10, integral time (τi) 1 minutes and 10 second as derivative time (τD). This parameter yields an oscillation response. This research aims to get the optimum PID parameters that can be applied to keep wastewater pH around 7. The experiment results show that the parameters of the PID controller Kc = 0.251, τi = 151 second = 2.51 minutes and τD = 12.5 second, had better performance than the PID controller parameters used previously.Air limbah yang dihasilkan dalam industri harus diolah terlebih dahulu, untuk memenuhi standar yang ditetapkan oleh Pemerintah. pH menjadi parameter penting dalam proses pengolahan air limbah. Seperti pada limbah industri serat sintetis mengandung ion yang membuat pH air limbah berkisar 2 hingga 3. Nilai ambang batas untuk pH air limbah, berdasarkan peraturan Menteri lingkungan, berkisar antara 6 hingga 9. Proses utama untuk mencapai standar ini adalah proses netralisasi. Pengontrol pH telah dipasang untuk memantau dan memenuhi target pH di tangki netralisasi. Pengontrol pH yang digunakan adalah jenis pengontrol PID (proporsional, integral, derivatif). Parameter PID yang digunakan dalam controller adalah proporsional gain (Kc) = 10, waktu integral = (τi) 1 menit dan waktu derivative (τD) = 10 detik. Parameter ini menghasilkan respons osilatif. Penelitian ini bertujuan untuk mendapatkan parameter PID optimal yang dapat diterapkan dalam IPAL sehingga pH air limbah bisa dikontrol pada kisaran pH 7. Hasil percobaan menunjukkan bahwa parameter pengontrol PID Kc = 0,251, τi = 151 detik = 2,51 menit dan τD = 12,5 detik, memiliki kinerja yang lebih baik daripada parameter pengontrol PID yang digunakan sebelumnya
Penumbuhan ZnO Rods Terdoping CeO2 Pada Substrat Kaca Menggunakan Metode Hidrotermal
Get PDFPure and cerium oxide (CeO2)-doped zinc oxide (ZnO) rods have been successfully grown on glass substrates using hydrothermal method. Growth of ZnO nanorods has two main processes, i.e. deposition of seed layer and growth of rods. The concentration ratios of Ce/ZnO are of about 1%, 5%, and 10%. The effect of CeO2 dopan on the structural and morphology of ZnO nanorods were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersion X-ray (EDX), and Fourier transform infrared (FTIR). The XRD spektrum on pure and CeO2-doped ZnO rods have hexagonal wurtzite structure with three highest peaks on the lattice of (100), (002), and (101), and face-centered cubic CeO2 phase on the lattice of (111) and (200). Analysis result of SEM confirmed that pure and CeO2-doped ZnO rods formed agglomeration of hexagonal flower-like rods. The addition of CeO2 shifted ZnO peaks of FTIR spectrum from 729 cm-1 to ~780 cm-1 .Seng oksida (ZnO) rods murni dan terdoping serium oksida (CeO2) telah ditumbuhkan di atas substrat kaca dengan menggunakan metode hidrotermal. Penumbuhan ZnO rods memiliki dua tahapan proses utama, yaitu pelapisan seed (pembenihan) dan penumbuhan rods. Rasio konsentrasi Ce/ZnO adalah sebesar 1%, 5%, dan 10%. Efek dopan CeO2 pada struktur dan morfologi ZnO rods dianalisa dengan X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersion X-ray (EDX), dan Fourier transform infrared (FTIR). Spektrum XRD dari ZnO rods murni dan terdoping CeO2 memiliki fasa hexagonal wurtzite ZnO dengan tiga puncak tertinggi pada bidang kisi (100), (002), (101), serta fasa face-centered cubic CeO2 pada bidang kisi (111) dan (200). Hasil analisis SEM mengonfirmasi bahwa bentuk ZnO murni dan terdoping CeO2 adalah gumpalan hexagonal flower-like rods. Penambahan CeO2 telah menggeser puncak spektrum FTIR ZnO murni dari 729 cm-1 menjadi ~780 cm-1
Laboratory Core-flooding Test of Surfactant-Polymer Injection Method for Oilfield Production Improvement
Get PDFThe utilization of chemical flooding to improve oil production in a large scale has many used for the oil field. Some cases have a success, and the others have fail when full scale project implemented. Before chemical flooding conducted, once of the recommended best practice to be done is chemical compatibility based on the reservoir characteristic of the layer as a target in improving oil recovery. Hence, coreflooding test in the laboratory to be an important thing to conduct in other to knows and determine the chemical performance after screening phase. The study of coreflooding test in the laboratory, shows that the measurement of surfactant and polymer properties have a good results to be used as an injection fluid in other to improve oil production. Surfactant - polymer injection which has concentrations of 3000 ppm and 1000 ppm with injection mechanism of 0.3 PV surfactant and 0.2 PV polymer gives the result of improving oil production it about 12.89%. Furthermore, based on the qualitative analysis obtained that the used of surfactant SS-B8020 as an injection fluid shown that plugging has not occurred in the reservoir rock pores, it means that the injection fluid was compatible with these reservoir rock
Tinjauan Potensi Pemanfaatan Botol Bekas Berbahan Polyethylene Terephthalate (PET) di Indonesia
No full textThe use of bottles made from Polyethylene Terephthalate (PET) has been increasing along with the development of ready-to-drink products. This type of packaging is very popular with the beverage industry because it is easily formed, strong, transparent, hygienic and economical. The increase in the use of PET bottles has an impact on the amount of waste that also increases so that it can become an environmental problem if it is not handled properly. The waste is still untapped in Indonesia, its utilization has only reached the stage of producing PET chopped which are then exported to countries that have beverage bottle recycling industries. This study aims to review the handling of used bottle waste, processing methods, shortcomings and advantages of products where this review is based on industry data and scientific articles. The consumption of beverages in PET bottle packaging which is increasing every year is a very promising potential for the development of research and the construction of industries related to processing used PET bottles in IndonesiaPenggunaan botol berbahan Polyethylene Terephthalate (PET) semakin meningkat dikarenakan berkembangnya produk minuman siap saji. Kemasan jenis ini sangat digemari oleh industri minuman karena mudah dibentuk, kuat, transparan, higienis dan ekonomis. Peningkatan dari penggunaan botol PET berdampak terhadap jumlah limbahnya yang turut meningkat sehingga dapat menjadi masalah lingkungan jika tidak ditangani dengan baik. Limbah tersebut masih belum termanfaatkan di Indonesia, pemanfaatannya baru sampai tahap menghasilkan cacahan PET yang selanjutnya diekspor ke Negara yang memiliki industri daur ulang botol minuman. Studi ini bertujuan untuk meninjau penanganan limbah botol bekas, metode pengolahan, kekurangan serta kelebihan dari produk dimana ulasan ini didasarkan pada data industri dan artikel ilmiah. Konsumsi minuman dalam kemasan botol PET yang cenderung meningkat setiap tahunnya merupakan potensi yang sangat menjanjikan untuk dikembangkannya penelitian maupun dibangunnya industri yang terkait dengan pengolahan limbah botol bekas berbahan PET di Indonesia
Karakteristik Hidroksiapatit Porous dari Prekursor Cangkang Keong Sawah dan Bahan Porogen Pati Sukun
Get PDFHydroxyapatite [Ca10(PO)4(OH)2] is a biomaterial used in bone implants to repair damaged tissue bones. Hydroxyapatite has biocompatible and osteoconductive properties. Hydroxyapatite synthesis is carried out by reacting Ca and P with a mole ratio of 1,67. One source of calcium precursors is conch shell with a CaCO3 content of 48,02%. The addition of porogen breadfruit starch serves to form pores so that it can accelerate the process of nutrient infiltration in bone. The study began with the calcination of conch shells at 900oC for 4 hours, to obtain calcium oxide (CaO) compounds. Calcium and phosphate reactions were carried out at 60oC and the stirring time was 3 hours. The hydroxyapatite produced was sintered at 900oC for 4 hours and analyzed using FTIR, AAS, UV-VIS, SEM, XRD, and compressive strength. The analysis solid and porous hydroxyapatite showed a comparison of calcium and phosphorus respectively 1.677 and 1.673, so that hydroxyapatite was close to the hydroxyapatite standard. Hydroxyapatite dense has a particle size of 0.396 μm, while porous hydroxyapatite has a particle size of 0.9135 μm and a pore of 0.655 μm. Hydroxyapatite dense and porous compressive strength are 19.61 MPa and 9,807 MPa respectively, so porous hydroxyapatite is more effective in nutrient infiltration to repair bone damage.Hidroksiapatit [Ca10(PO)4(OH)2] adalah biomaterial yang digunakan dalam bone graft implan tulang untuk memperbaiki jaringan-jaringan yang rusak dan tulang yang patah. Hidroksiapatit memiliki sifat biokompatibel dan osteokonduktif. Sintesis hidroksiapatit dilakukan dengan mereaksikan Ca dan P dengan perbandingan mol 1,67. Salah satu sumber prekursor kalsium adalah cangkang keong dengan kandungan CaCO3 53,10%. Penambahan bahan porogen pati sukun berfungsi untuk membentuk pori sehingga dapat mempercepat proses infiltrasi nutrisi pada tulang. Penelitian diawali dengan proses kalsinasi cangkang keong pada suhu 900oC selama 4 jam, untuk mendapatkan senyawa kalsium oksida (CaO). Reaksi kalsium dan posfat dilakukan pada suhu 60oC dan variasi waktu stirring 3 jam. Hidroksiapatit yang dihasilkan disintering pada suhu 900oC dengan waktu 4 jam dan dianalisis kualitas dan morfologinya menggunakan FTIR, AAS, UV-VIS, SEM, XRD, dan kuat tekan. Hasil analisis menunjukkan perbandingan kalsium dan fosfor untuk hidroksiapatit dense dan porous masing-masing 1,677 dan 1,673, sehingga hidroksiapatit mendekati hidroksiapatit standar. Hidroksiapatit dense memiliki ukuran partikel 0,396 µm, sedangkan hidroksiapatit porous memiliki ukuran partikel 0,9135 µm dan pori 0,655 µm. Kuat tekan hidroksiapatit dense dan porous masing-masing 19,61 MPa dan 9,807 MPa, sehingga hidroksiapatit porous lebih efektif dalam infiltrasi nutrisi untuk memperbaiki kerusakan tulang
Degradasi Limbah Zat Warna Direk Dengan Metode Advanced Oxidation Processes (AOPs) Kombinasi H2O2/MnO2 dengan Parameter Uji BOD, COD dan pH
Get PDFAdvanced Oxidation Processes (AOPs) method has been applied and is growing in number of textile wastewater treatment. Textile industries are commonly using synthetic dyes in the dyeing process and will produce coloured-wastewater that is still contain of organic compound and is hard to be degraded. One of most frequently used synthetic dyes in textile industries is direct dyes. Direct dyes wastewater consists of azo bound whereby difficult to eliminate the colour and the concentration itself, thus an appropriate treatment such as AOPs is considered. The AOPs process to degrade direct dyes wastewater in this research uses a combination of H2O2 with catalyst MnO2. Parameter variation that carried out, are the variation of the ratio of wastewater and H2O2 volume, namely 1:1; 2:1 and 1:2. Whilst the using of mass of catalyst MnO2 is 1 g for each sample variation, namely 1 g for 250 ml and 500 ml H2O2. The results obtained after the BOD, COD and pH tests, are 230 mg/l, 784 mg/l and 5,26 respectively. This result is showed by the sample with variation 2:1 which is delivering the lowest values of BOD, COD and pH amongst the three sample variations mentionedABSTRAK: Metode AOPs (Advanced Oxidation Processes) telah banyak digunakan dan semakin berkembang untuk diaplikasikan pada pengolahan limbah tekstil. Perusahaan tekstil biasanya menggunakan zat warna sintetis dan menghasilkan limbah berwarna yang masih mengandung senyawa organik dan sulit untuk didegradasi. Salah satu zat warna yang paling sering digunakan adalah zat warna direk. Limbah zat warna direk mengandung ikatan azo yang sulit untuk didegradasi sehingga membutuhkan penanganan yang tepat seperti dengan metode AOPs. Proses AOPs untuk mendegradasi zat warna direk pada penelitian ini menggunakan kombinasi larutan H2O2 dengan katalis MnO2. Parameter yang dilakukan antara lain variasi perbandingan volume limbah dengan larutan H2O2 50% yaitu 1:1; 2:1 dan 1:2. Sedangkan massa MnO2 yang digunakan adalah 1 g untuk setiap variasi perbandingan yang dilakukan, yaitu 1 g untuk 250 ml dan 500 ml larutan H2O2. Setelah dilakukan pengujian dengan parameter BOD, COD dan pH diperoleh hasil BOD, COD dan pH terendah pada sampel percobaan dengan variasi 2:1, yaitu sebesar 230 mg/l, 784 mg/l dan 5,26.Kata Kunci: AOPs; degradasi; H2O2/MnO2; limbah tekstil; zat warna direk ABSTRACT: Advanced Oxidation Processes (AOPs) method has been applied and is growing in number of textile wastewater treatment. Textile industries are commonly using synthetic dyes in the dyeing process and will produce coloured-wastewater that is still contain of organic compound and is hard to be degraded. One of most frequently used synthetic dyes in textile industries is direct dyes. Direct dyes wastewater consists of azo bound whereby difficult to eliminate the colour and the concentration itself, thus an appropriate treatment such as AOPs is considered. The AOPs process to degrade direct dyes wastewater in this research uses a combination of H2O2 with catalyst MnO2. Parameter variation that carried out, are the variation of the ratio of wastewater and H2O2 volume, namely 1:1; 2:1 and 1:2. Whilst the using of mass of catalyst MnO2 is 1 g for each sample variation, namely 1 g for 250 ml and 500 ml H2O2. The results obtained after the BOD, COD and pH tests, are 230 mg/l, 784 mg/l and 5,26 respectively. This result is showed by the sample with variation 2:1 which is delivering the lowest values of BOD, COD and pH amongst the three sample variations mentioned.Keywords: AOPs; degradation; direct dyes; H2O2/MnO2; textile wastewate
Penerapan Lima Model Kesetimbangan Adsorpsi Isoterm pada Adsorpsi Ion Logam Chrom VI oleh Zeolit
Get PDFChrom VI metal ion include heavy metal waste which needs further processing using adsorbent. Zeolite is a suitable adsorbent for absorbing strong affinity chrom VI metal ions because zeolite is a natural mineral that has an active surface area per unit of mass and power. The purpose of this study was to determine a suitable model for the equilibrium adsorption of chrom VI metal ion by zeolite along with their parameter values, and to determine the optimal zeolite absorption against chrom VI metal ion. This study uses the method of applying the isotherm adsorption equilibrium model which includes 5 equations namely Linear Adsorption (Henry\u27s Law), Freundlich Isotherm Adsorption, Langmuir Isoterm Adsorption, Brunauer-Emmett-Teller Isotherm (BET), Sigmoidal Chapman Equation. From these five models, data fitting is done to find models that are closer to the data. Data matching is done by minimizing the Matlab program. The results showed that the suitable model is the BET Isotherm Adsorption model with parameter values, namely the BET isotherm adsorption constant value (CBET) of 0.5183 l/mg, the maximum capacity of the adsorbent at equilibrium theoretical (qs) is 149.9977 mg/g and the saturated adsorbate concentration in the monolayer (Cs) is 184.1691 mg l.ABSTRAK: Ion logam chrom VI termasuk limbah logam berat yang perlu dilakukan pengolahan lebih lanjut dengan menggunakan adsorben. Zeolit adalah adsorben yang cocok untuk menyerap ion logam chrom VI karena zeolit merupakan mineral alam yang mempunyai luas permukaan aktif per satuan massa yang besar dan daya afinitas yang cukup kuat. Tujuan dari penelitian ini adalah menentukan model yang cocok untuk kesetimbangan adsorpsi ion logam chrom VI oleh zeolit beserta nilai parameternya, dan mengetahui daya serap zeolit optimal terhadap ion logam chrom VI. Penelitian ini mengunakan metode penerapan model kesetimbangan adsorpsi isoterm yang meliputi 5 persamaan yaitu Adsorpsi Linier (Henry’s Law), Adsorpsi Isoterm Freundlich, Adsorpsi Isoterm Langmuir, Isoterm Brunauer-Emmett-Teller (BET), Persamaan Sigmoidal Chapman. Dari kelima model ini dilakukan fitting data untuk mencari model yang lebih mendekati data. Pencocokan data dilakukan dengan minimasi yang dilakukan oleh program Matlab. Hasil penelitian menunjukkan bahwa model yang cocok yaitu model Adsorpsi Isoterm BET dengan nilai parameter yaitu nilai konstanta adsorpsi isoterm BET (CBET) sebesar 0,5183 l/mg, kapasitas maksimal adsorben saat setimbang secara teoritis (qs) adalah 149,9977 mg/g dan konsentrasi adsorbat jenuh pada lapisan monolayer (Cs) adalah 184,1691 mg/l.Kata Kunci: Adsorben; Isoterm BET; Model Kesetimbangan Adsorpsi; Zeolit ABSTRACT: Chrom VI metal ion include heavy metal waste which needs further processing using adsorbent. Zeolite is a suitable adsorbent for absorbing strong affinity chrom VI metal ions because zeolite is a natural mineral that has an active surface area per unit of mass and power. The purpose of this study was to determine a suitable model for the equilibrium adsorption of chrom VI metal ion by zeolite along with their parameter values, and to determine the optimal zeolite absorption against chrom VI metal ion. This study uses the method of applying the isotherm adsorption equilibrium model which includes 5 equations namely Linear Adsorption (Henry\u27s Law), Freundlich Isotherm Adsorption, Langmuir Isoterm Adsorption, Brunauer-Emmett-Teller Isotherm (BET), Sigmoidal Chapman Equation. From these five models, data fitting is done to find models that are closer to the data. Data matching is done by minimizing the Matlab program. The results showed that the suitable model is the BET Isotherm Adsorption model with parameter values, namely the BET isotherm adsorption constant value (CBET) of 0.5183 l/mg, the maximum capacity of the adsorbent at equilibrium theoretical (qs) is 149.9977 mg/g and the saturated adsorbate concentration in the monolayer (Cs) is 184.1691 mg l.Keywords: Adsorbent; BET Isotherm; Adsorption Equilibrium Model; Zeolit