Methyl esters selectivity of transesterification reaction with homogenous alkaline catalyst to produce biodiesel in batch, plug flow, and continuous stirred tank reactors

Selectivity concept is essential in establishing the best operating conditions for attaining maximum production of the desired product. For complex reaction such as biodiesel fuel synthesis, kinetic studies of transesterification reaction have revealed the mechanism of the reaction and rate constants. The objectives of this research are to develop the kinetic parameters for determination of methyl esters and glycerol selectivity, evaluate the significance of the reverse reaction in transesterification reaction, and examine the influence of reaction characteristics (reaction temperature, methanol to oil molar ratio, and the amount of catalyst) on selectivity. For this study, published reaction rate constants of transesterification reaction were used to develop mathematical expressions for selectivities. In order to examine the base case and reversible transesterification, two calculation schemes (Case 1 and Case 2) were established. An enhanced selectivity was found in the base case of transesterification reaction. The selectivity was greatly improved at optimum reaction temperature (60 C), molar ratio (9 : 1), catalyst concentration (1.5 wt.%), and low free fatty acid feedstock. Further research might explore the application of selectivity for specifying reactor configurations

Compacted nanosilica-talic/calcium carbonate polyacrylate composites prepared using accelerated sedimentation

The effectiveness of centrifugation as the compacting method in preparing high filler composites has been investigated. Different size and shape of fillers were used to ensure efficient filler space filling. In situ polymerization of bisphenol-A ethoxy diacrylate after centrifugating produced biomimetic composites with 74–86 % filler content. The filler space was efficiently filled by using a combination of nano and microsize fillers, especially in the nanosilica-CaCO3 composite. The morphology of the composites indicates that the fillers were well dispersed and embedded in the polymer matrix. The etched surface of the nanosilica-talc composite reveals that the combination of talc and nanosilica formed a biomimetic composite that displayed an ordered brick-and-mortar nacre-like structure. The wide-angle X-ray diffraction patterns indicate the crystal structure of CaCO3 and talc were maintained in the composit

Analisis Faktor-Faktor yang Mempengaruhi Rasio Pembayaran Dividen pada PT. Indofood Sukses Makmur di Bursa Efek Indonesia (BEI)

Tujuan dari penelitian ini adalah untuk mengetahui pengaruh Free Cash Flow (Aliran Kas Bebas) dan Return On Asset (ROA) terhadap Rasio Pembayaran Dividen pada PT. Indofood Sukses Makmur di Bursa Efek Indonesia (BEI). Alat analisis yang digunakan dalam penelitian ini adalah regresi linear berganda dengan Rasio Pembayaran Dividen yang diukur berdasarkan rasio antara devidend per share dengan earning per share yang dalam persentase menjadi variabel dependen dan dua variabel independen, yaitu Free Cash Flow yang diukur berdasarkan antara cash flow from operation dengan capital expenditures dan Return On Asset (ROA) yang diukur berdasarkan persentase dari rasio antara laba bersih setelah pajak dengan total aktiva. Data yang digunakan adalah data sekunder yang diperoleh dari laporan keuangan PT. Indofood Sukses Makmur di Bursa Efek Indonesia (BEI), dengan teknik dokumentasi serta laporan keuangan. Olah data menggunakan regresi linear berganda.Hasil pengolahan data diperoleh model Y = 22,508 + 0,00003515 X1 + 5,595 X2. Secara parsial, hasil uji t menunjukkan bahwa variabel Free Cash Flow (FCF)= 4,033 dan Return On Asset (ROA) = 3,793 berpengaruh positif dan signifikan terhadap Rasio Pembayaran Dividen karena thitung > ttabel = 2,365. Berdasarkan hasil simultan diperoleh nilai F sebesar 4,989 dengan tingkat probabilitas 0,033 ini menunjukkan bahwa secara bersama-sama variabel independen, yaitu Free Cash Flow dan ROA berpengaruh secara signifikan terhadap Rasio Pembayaran Dividen pada PT. Indofood Sukses Makmur di Bursa Efek Indonesia (BEI). Nilai Koefisien Determinasi (R2) adalah 0,563, hal inimenunjukkan bahwa variabel independen yang diteliti mampu menjelaskan 56,3 persen terhadap variabel Rasio Pembayaran Dividen

Methyl esters selectivity of transesterification reaction with homogenous alkaline catalyst to produce biodiesel in batch, plug flow, and continuous stirred tank reactors

Selectivity concept is essential in establishing the best operating conditions for attaining maximum production of the desired product. For complex reaction such as biodiesel fuel synthesis, kinetic studies of transesterification reaction have revealed the mechanism of the reaction and rate constants. The objectives of this research are to develop the kinetic parameters for determination of methyl esters and glycerol selectivity, evaluate the significance of the reverse reaction in transesterification reaction, and examine the influence of reaction characteristics (reaction temperature, methanol to oil molar ratio, and the amount of catalyst) on selectivity. For this study, published reaction rate constants of transesterification reaction were used to develop mathematical expressions for selectivities. In order to examine the base case and reversible transesterification, two calculation schemes (Case 1 and Case 2) were established. An enhanced selectivity was found in the base case of transesterification reaction. The selectivity was greatly improved at optimum reaction temperature (60 C), molar ratio (9 : 1), catalyst concentration (1.5 wt.%), and low free fatty acid feedstock. Further research might explore the application of selectivity for specifying reactor configurations

Estimation of temperature and electron density in stainless steel plasma using laser induced breakdown spectroscopy

LIBS plasma produced by a 1064 nm Q-switched Nd:YAG laser in an atmospheric pressure was studied for the stainless steel sample. The laser output energy 150 mJ with pulse duration of 6 ns. The plasma emission spectrum was recorded by the LR1 Spectrometer connected to the fibre optic. The plasma temperature and electron density of each element were estimated by time-resolved spectroscopy of neutral atom and ion line emission. The plasma temperature was obtained from the Boltzmann plot method and their electron density was determined by using Saha-Boltzmann equation method. The preliminary qualitative LIBS analysis shows that several elements contained in the stainless steel. The element detected was Cu, Fe, Mn, Ni, and Cr. The results shows that Mn and Fe has the highest plasma temperature of 1.2 eV, but the electron density of Mn was the highest with value 4.6x1020 cm-3, while the Cu has the lowest temperature that is 0.73 eV with the electron density 2.8x1017 cm-3. The results are discussed

Analisis Kelayakan USAha Agroindustri Tempe

Penelitian ini bertujuan untuk mengetahui: (1) besarnya biaya, penerimaan, dan pendapatan agroindustri tempe di Desa Pawindan Kecamatan Ciamis Kabupaten Ciamis; (2) kelayakan USAha agroindustri tempe di Desa Pawindan Kecamatan Ciamis Kabupaten Ciamis. Penelitian dilaksanakan di Desa Pawindan Kecamatan Ciamis Kabupaten Ciamis dengan menggunakan metode survai. Sampel lokasi ditentukan secara sengaja (purposive) dengan pertimbangan bahwa Desa Pawindan merupakan sentra agroindustri tempe di Kecamatan Ciamis. Teknik penarikan responden dilakukan secara sensus. Hasil penelitian menunjukkan bahwa: Rata-rata biaya total sebesar Rp 1.274.208,90, yang dihasilkan dari penjumlahan biaya tetap rata-rata sebesar Rp 17.427,24, dengan biaya variable rata-rata sebesar Rp 1.256.781,70. Pendapatan rata-rata yang diperoleh sebesar Rp 644.791,09, dari penerimaan rata-rata sebesar Rp 1.919.000,00,- dikurangi biaya total rata-rata sebesar Rp 1.274.208,90. Analisis Kelayakan yang digunakan yaitu analisis kelayakan USAha yang membandingkan antara penerimaan dan biaya total. Rata-rata penerimaan yang diperoleh sebesar Rp 1.919.000,00,- dan biaya total rata-rata yang dikeluarkan sebesar Rp 1.274.208,90. Dengan demikian diperoleh R/C sebesar 1,50 artinya berarti bahwa USAha agroindustri tempe layak untuk dijalankan