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Ditemukan 4 dokumen yang sesuai dengan query
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Agus Mirwan
"The kinetics of aluminum
leaching from sludge solid waste (SSW) using hydrochloric acid at different
leaching temperatures (30-90°C) was studied. A mathematical model was developed based on a
shrinking core model by assuming first-order kinetics mechanisms for leaching
and an equilibrium linear at the solid-liquid
interface. The proposed model is suited to fit experimental data with three
fitting parameters and to simulate the leaching of aluminum from SSW, which was
validated with the mass transfer coefficient (kc, cm/s),
diffusion coefficient (De,
cm2/s), and reaction rate constants (k, cm/s). The evaluated kc,
De, and k are expected to follow an increasing
trend with increasing temperature. The correlation coefficient ≥ 0.9795, the
root mean square error ≤ 0.399, the mean relative deviation modulus ≤ 6.415%,
and the value of activation energy is 13.27 kJmol-1. The proposed model could describe the kinetics of
aluminum leaching from the SSW DWT in accordance with test parameters and
relevant statistical criteria. Valuable information on the results of this work
can be given for the purposes of the simulation, optimization, scaling-up, and
design of the leaching
process."
2017
J-Pdf
Artikel Jurnal  Universitas Indonesia Library
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Agus Mirwan
"The kinetics of aluminum leaching from sludge solid waste (SSW) using hydrochloric acid at different leaching temperatures (30-90°C) was studied. A mathematical model was developed based on a shrinking core model by assuming first-order kinetics mechanisms for leaching and an equilibrium linear at the solid-liquid interface. The proposed model is suited to fit experimental data with three fitting parameters and to simulate the leaching of aluminum from SSW, which was validated with the mass transfer coefficient (kc , cm/s), diffusion coefficient (De, cm2/s), and reaction rate constants (k, cm/s). The evaluated kc , De , and k are expected to follow an increasing trend with increasing temperature. The correlation coefficient ? 0.9795, the root mean square error ? 0.399, the mean relative deviation modulus ? 6.415%, and the value of activation energy is 13.27 kJmol-1. The proposed model could describe the kinetics of aluminum leaching from the SSW DWT in accordance with test parameters and relevant statistical criteria. Valuable information on the results of this work can be given for the purposes of the simulation, optimization, scaling-up, and design of the leaching process."
Depok: Faculty of Engineering, Universitas Indonesia, 2017
UI-IJTECH 8:1 (2017)
Artikel Jurnal  Universitas Indonesia Library
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Muhammad Irfan Salahuddin
"Penelitian ini bertujuan untuk mendapatkan model matematis yang valid untuk ekstraktor unggun diam untuk proses ekstraksi asam lemak dari mikroalga Nannochloropsis sp. dan mendapatkan parameter kinetika ekstraksi asam lemak dari Nannochloropsis sp. Ekstraksi senyawa asam lemak dilakukan menggunakan metode ekstraksi fluida superkritis (EFS) dengan fluida superkritis CO2. Dalam penelitian ini, proses EFS akan dipelajari dengan menggunakan model inti menyusut, dan perhitungan model terkait neraca massa proses ekstraksi dilakukan secara numeris metode implisit Crank-Nicolson dengan program MATLAB R2020b. Estimasi parameter-parameter proses ekstraksi asam lemak dari mikroalga Nannochloropsis sp. dengan fluida CO2 superkritis telah berhasil dilakukan. Nilai konsentrasi awal solut dalam padatan adalah 420 mol/m3. Parameter-parameter nilai koefisien difusivitas efektif solut dalam pelarut, koefisien perpindahan massa solut dalam fluida-padat, dan nilai konsentrasi jenuh masing-masing diperoleh pada empat kondisi operasi, yaitu pada suhu 313 K dan tekanan 12,5 MPa, 20 MPa, 30 MPa, dan juga pada suhu 333 K dan tekanan 30 MPa. Nilai deviasi relatif mutlak (AARD) yang didapat setelah membandingkan hasil simulasi dengan data eksperimen rata-rata adalah masing-masing sebesar 4,481%, 3,628%, 16,846%, dan 32,328% untuk kondisi operasi 313 K dan 12,5 MPa, 313 K dan 20 MPa, 313 K dan 30 MPa, dan 333 K dan 30 MPa, yang menandakan model ini kurang dapat mereproduksi hasil eksperimen ekstraksi asam lemak dari Nannochloropsis sp. pada tekanan tinggi.

The purpose of this research experiment is to obtain a valid mathematical model for fixed bed extractor extraction process of fatty acid from microalgae Nannochloropsis sp. and obtaining fatty acid extraction kinetic parameters from microalgae Nannochloropsis sp. Supercritical fluid extraction (SFE) method with CO2 supercritical fluid is used as the extraction method to extract the fatty acid compounds from microalgae Nannochloropsis sp. In this research, study of SFE process will use the shrinking core model and calculations related to mass balances of the extraction process will be carried out numerically by Crank-Nicolson implicit method using MATLAB R2020b program. Process parameters estimation of fatty acid supercritical fluid extraction from spent coffee grounds had been carried out successfully. Initial solid solute concentration value is 420 mol/m3. Extraction parameters, which are effective diffusivity coefficient, solute in solid-fluid mass transfer coefficient, and saturated concentration are each obtained under four operating conditions, namely at a temperature of 313 K and a pressure of 12.5 MPa, 20 MPa, 30 MPa, and at a temperature of 333 K and a pressure of 30 MPa. Comparison of reference experimental data with simulation from this experiment resulted on AARD values (average absolute relative deviation) of 4.65%, 12.87%, 4.19%, and 4.29% for 313K and 12.5MPa, 313K and 20MPa, 313K and 30MPa and 333K and 333K and 30MPa respectively, which shows that this model is less able to reproduce the experimental results of fatty acid extraction from Nannochloropsis sp. at high pressure."
Depok: Fakultas Teknik Universitas Indonesia, 2021
S-pdf
UI - Skripsi Membership  Universitas Indonesia Library
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Rakha Putra Prasetya
"Indonesia adalah negara yang kaya akan tanaman herbal untuk mengobat berbagai jenis penyakit. Tanaman herbal memiliki senyawa bioaktif Bernama asam fenolat dengan sifat anti-inflamasi, anti-penuaan, dan antioksidan,. Salah satu tanamannya adalah kejibeling atau Strobilanthes crispus. Senyawa bioaktif bekerja paling baik dengan cara diekstraksi. Proses ini dimodelkan untuk menggambarkan fenomena proses ekstraksi dengan model inti menyusut. Model ini disimulasikan dengan ekstraksi asam fenolat berdasarkan data eksperimen. Model orde dua diterapkan untuk menggambarkan kinetika. Variasi untuk simulasi adalah 30, 40, 50, dan 60°C dan konsentrasi enzim 3, 5, dan 7%. Simulasi yang dimodelkan menghasilkan konsentrasi awal (Cc), faktor pra-eksponensial (kd00), energi aktivasi (Ea), dan koefisien difusi (Dl). Parameter yang dihasilkan adalah nilai Cc sebesar 0,889 kmol/m3 dan kd00 sebesar 1,565E-03 m/s untuk semua suhu dan konsentrasi enzim. Nilai Ea adalah 1,20E+07 untuk enzim 3%, 1,145E+07 untuk enzim 5%, dan 1,07E+07 J/kmol untuk enzim 7%. Nilai Dl adalah 1,889E-06, 1,833E-06, dan 1,792E-06 m2/s pada suhu 30°C dan konsentrasi enzim 3, 5, dan 7%, 1,6746E-06, 1,5437E-06, dan 1,5267E-06 m2/s pada suhu 40°C dan konsentrasi enzim 3, 5, dan 7%. 3844E-06, 1.2495E-06, dan 1.2165E-06 m2/s pada suhu 50°C dan konsentrasi enzim 3, 5, dan 7%, serta 9.254E-07, 9.061E-07, dan 8.683E-07 m2/s pada suhu 60°C dan konsentrasi enzim 3, 5, dan 7%.

Indonesia is a country rich with herbal plants for the treatment of a variety of diseases. Herbal plants contain bioactive compounds called phenolic acids with anti-inflammatory, anti-aging, and antioxidant properties. One of the herbal plants is kejibeling or Strobilanthes crispus. The bioactive compounds work best by being extracted. The process is modelled for describing the phenomena of extraction process with the shrinking core model. The model is simulated with the extractions of phenolic acids based on experimental data. The second-order model is applied for describing kinetics. The variations for the simulation are 30, 40, 50, and 60°C and enzyme concentrations of 3, 5, and 7%. The modelled simulation yields initial concentrations (Cc), pre-exponential factor (kd00), activation energy (Ea), and diffusion coefficient (Dl). The resulting parameters are Cc values of 0.889 kmol/m3 and kd00 of 1.565E-03 m/s for all temperature and enzyme concentrations. The Ea value is 1.20E+07 for 3% enzyme, 1.145E+07 for 5% enzyme, and 1.07E+07 J/kmol for 7% enzyme. The Dl values are 1.889E-06, 1.833E-06, and 1.792E-06 m2/s at 30°C and enzyme concentrations of 3, 5, and 7%, respectively, 1.6746E-06, 1.5437E-06, and 1.5267E-06 m2/s at 40°C and enzyme concentrations of 3, 5, and 7%, respectively, 1.3844E-06, 1.2495E-06, and 1.2165E-06 m2/s at 50°C and enzyme concentrations of 3, 5, and 7%, respectively, and 9.254E-07, 9.061E-07, and 8.683E-07 m2/s at 60°C and enzyme concentrations of 3, 5, and 7%, respectively."
Depok: Fakultas Teknik Universitas Indonesia, 2024
S-pdf
UI - Skripsi Membership  Universitas Indonesia Library