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Persamaan Empiris Sederhana untuk Memprediksikan Ukuran Partikel dari Enkapsulasi Oleoresin Jahe Merah Jayanudin Jayanudin; Rochmadi Rochmadi; Moh. Fahrurrozi; Sang Kompiang Wirawan
ALCHEMY Jurnal Penelitian Kimia Vol 14, No 2 (2018): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.14.2.17076.178-192

Abstract

Tujuan penelitian ini adalah menentukan persamaan empiris dari bilangan tak berdimensi untuk memprediksikan ukuran mikrokapsul oleoresin jahe merah. Metode enkapsulasi yang digunakan adalah crosslink emulsi dengan kitosan sebagai penyalut dan glutaraldehyde saturated toluene (GST) sebagai agen crosslink. Oleoresin jahe merah dan kitosan dengan konsentrasi 1, 2, 3 dan 4% (w/v) diaduk dengan kecepatan 10.000 rpm untuk membentuk emulsi, kemudian dimasukan dalam minyak jagung dan diaduk kembali untuk membentuk emulsi kedua. Sebanyak 10 mL glutaraldehyde saturated toluene (GST) sebagai agen crosslink ditambahkan secara bertahap. Setelah itu, ditambahkan larutan glutaraldehida 25% dan terus diaduk selama 2 jam. Mikrokapsul dipisahkan dan dicuci dengan petroleum eter dan heksan, kemudian dikeringkan dalam oven dengan suhu 70 °C. Dengan cara yang sama digunakan untuk membuat mikrokapsul pada kecepatan pengadukan 5.000, 8.000 dan 15.000 rpm. Ukuran diameter mikrokapsul dianalisis menggunakan mikroskop digital. Persamaan empiris dari bilangan tak berdimensi Reynolds (Re) dan Ohnesorge (Oh) dibuat untuk memprediksikan diameter mikrokapsul. Data dari variabel perubahan konsentrasi kitosan dan kecepatan pengadukan dapat menghasilkan persamaan empiris dari bilangan Reynolds (Re) dan Ohnesorge (Oh). Konstanta yang dihasilkan adalah  = 422,06,  = 0,37 dan  = -0,18. Berdasarkan perbandingan antara data diameter penelitian dan hasil perhitungan didapat % kesalahan sebesar 8,05% untuk pengaruh konsentrasi kitosan dan 7,52% untuk pengaruh kecepatan pengadukan.A Simple Empirical Equation for Predicting Particle Size from Encapsulation of Red Ginger Oleoresin. This study aims to determine the empirical equations of the dimensionless number to predict the diameter size of red ginger oleoresin microcapsules. The encapsulation method used is crosslinking emulsion with chitosan as coating and glutaraldehyde saturated toluene (GST) as a crosslinking agent. Red ginger oleoresin and chitosan with concentrations of 1, 2, 3 and 4% (w/v) were stirred at 10,000 rpm to form emulsions, and then added to the corn oil and stirred again to form a second emulsion. The 10 mL of glutaraldehyde saturated toluene (GST) as a crosslinking agent was added gradually. After that, a 25% glutaraldehyde solution was added and stirred for 2 hour. Microcapsules were separated and washed with petroleum ether and hexane, then dried in an oven at a temperature 70 °C. The same step, the microcapsules were made at stirring speed of 5,000; 8,000; and 15,000 rpm. The size of the microcapsule diameter was analyzed using a digital microscope. The empirical equations of the dimensionless numbers Reynolds (Re) and Ohnesorge (Oh) are made to predict the microcapsule diameter. The data from the chitosan concentration change and stirring speeds could produce the empirical equations of the Reynolds and Ohnesorge numbers. The resulting constants were  = 422.06,  = 0.37 dan  = -0.18. By comparing the data diameter of the research and calculation results obtained % error of 8.05% for the influence of chitosan concentration and 7.52% for the effect of stirring speed. 
Mathematical Modeling of Reactive Extraction of Solute from Slab Solid Material Indah Hartati; Hary Sulistyo; Wahyudi Budi Sediawan; Muhammad Mufti Azis; Moh Fahrurrozi
Indonesian Journal of Chemistry Vol 20, No 2 (2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (16.081 KB) | DOI: 10.22146/ijc.47181

Abstract

Reactive extraction is gaining higher attention due its wide application in various solute separation processes. Here, a mathematical model of reactive extraction in slab has been proposed. The model was developed by considering simultaneous processes of active compound intra particle diffusion, second order elemental reaction of solute-active compound, and intra-particle product diffusion. The obtained partial differential equations (PDEs) were solved using Finite Difference Approximation (FDA) method by using realistic parameters. Concentration profile as well as product yield were evaluated as a function of time. As a result, the model proposed here may serve as a basis design for reactive extraction unit. Sensitivity analyses was conducted to inspect the influence of slab thickness, diffusivity and reaction rate constant to the product yield. Eventually, model validation was conducted by comparing the simulation results with analytical solutions for special cases. Validation results showed that the model gave good agreement with the analytical solution.
Removing Ethylene by Adsorption using Cobalt Oxide-Loaded Nanoporous Carbon Imam Prasetyo; Nur Indah Fajar Mukti; Moh Fahrurrozi; Teguh Ariyanto
ASEAN Journal of Chemical Engineering Vol 18, No 1 (2018)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1011.751 KB) | DOI: 10.22146/ajche.49542

Abstract

Ethylene is naturally generated by climacteric fruits and can promote the ripening process faster. For effective long-distance transport and subsequent storage, removing ethylene from the storage environment has been of interest to suppress its undesirable effect. In this study, ethylene removal by an adsorptive method using cobalt-loaded nanoporous carbon is studied. Cobalt oxide-loaded carbon was prepared by incipient wetness method followed by calcination process at 200 °C under inert flow. Ethylene adsorption test was performed at 20, 30, and 40 °C using a static volumetric test. The results showed that cobalt oxide/carbon system has significant ethylene adsorption capacity up to 3.5 times higher compared to blank carbon. A higher temperature adsorption is more favorable for this chemisorption process. Ethylene uptake increases from 100 to 150 mL g-1adsorbent STP by increasing cobalt oxide loading on carbon from 10 to 30 wt.% Co. The highest uptake capacity of 6 mmol ethylene per gram adsorbent was obtained using 30 wt.% cobalt oxide. Therefore, ethylene adsorption by cobalt-loaded nanoporous carbon may represent a potential method in ethylene removal and it could serve as a basis for development of ethylene scavenging material.
Thermodynamics Analysis on Methane Hydrate Formation in Porous Carbon Wibiana W. Nandari; Imam Prasetyo; Moh. Fahrurrozi
ASEAN Journal of Chemical Engineering Vol 16, No 2 (2016)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1156.984 KB) | DOI: 10.22146/ajche.49891

Abstract

Methane is a potential alternative energy source which is abundant and produces lower CO2 emissions when it is used as fuel due to the content of C in the methane molecule is much lesser than its H content. Besides in a form of gas, methane in nature can also be in the form of methane hydrates. The formation process of methane hydrates in nature can be adopted as a method of storage of methane. In this study, a thermodynamics review will be studied related to temperature and pressure in a phase equilibrium system of methane hydrate . Thermodynamic model aims to predict the stability of methane hydrates for effective storage of methane. Each volume of methane hydrate contains as 164 volumes of methane gas under standard conditions ( STP ). The study was conducted by adsorbing methane on a wet porous carbon with the method of static volumetric.. The experimental results show that at the temperature of 274 K methane hydrates was formed at a pressure of 2.75 MPa; at a temperature of 275 K, pressure of 3.16 MPa; at a temperature of 276 K, pressure of 3.44 MPa, while at a temperature of 277 K, pressure of 3.67 MPa. Temperatures and pressures data are used to calculate the parameters of Langmuir equation constants modeled by the Van der Waals - Platteeuw for the chemical potential of water in the hydrate phase, Holder et al for the chemical potential of water in the liquid phase, as well as for the Gibbs-Thomson effect of porous carbon media.
Synthesis and Characterization of Hybridfiber from Gelatin Modified by PVACOS Using Coaxial Electrospinning Techniques as an Advanced Medical Textile Material Siti Fatimah; Sarto Sarto; Moh. Fahrurrozi; Budhijanto Budhijanto
Emerging Science Journal Vol 8, No 2 (2024): April
Publisher : Ital Publication

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.28991/ESJ-2024-08-02-022

Abstract

The synthesis of hybrid fiber based on bovine bone gelatin combined with polyvinyl alcohol-chitosan-oxidized sucrose (PVACOS) has been successfully carried out using the coaxial electrospinning technique. The presence of oxidized sucrose can improve the diameter and the tensile strength of hybrid fibers due to the formation of new covalent bonds. The combination of gelatin with PVACOS material aims to increase the strength of the hybrid fiber so that it has better tensile strength characteristics and improves the diameter of the resulting hybrid fiber. The characterization of the resulting material was tested using FTIR, SEM, EDX, XRD, and TGA. Based on FTIR analysis, there is an increase in absorption intensity in the 2900 cm-1 – 3000 cm-1 band, which indicates the occurrence of covalent bond interactions so that it can increase the bond strength between materials with the performance of crystalline materials. Apart from that, the morphological structure of the hybrid fibers was also investigated using scanning electron microscopy (SEM), and the resulting fiber diameter for Ge-Ch, Ge-Ch-PVA, Ge-PVACOS 3%, and Ge-PVACOS 5%, respectively, was 0.4049 µm. 0.3735 µm, 0.3388 µm, and 0.3206 µm. The tensile strengths of hybrid fiber for Ge-PVACOS 3% and Ge-PVACOS 5%, respectively, are 39.91935 N/m2 and 76.12507 N/m2. Statistical tests show that the concentration of oxidized sucrose has a significant influence on hybrid fiber performance. The significance values for diameter and tensile strength are 0.0486 and 0.0325, respectively. According to this performance, the Ge-PVACOS hybrid fiber is recommended as a material for advanced medical textiles. Doi: 10.28991/ESJ-2024-08-02-022 Full Text: PDF
Studi tekno-ekonomi pemurnian biogas dari limbah domestik Akhwari Wahyu P; Moh Fahrurrozi; Muslikhin Hidayat
Jurnal Rekayasa Proses Vol 6 No 2 (2012): Volume 6, Number 2, 2012
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.4695

Abstract

Biogas purification can increase the caloric value of combustion and prevent corrosion. Biogas with 95% of methane is similar to pipeline quality natural gas. The objective of this research was to study technical and economical feasibility of biogas purification and also to estimate gas production cost and scale up capacities.This research used the secondary data from pilot plant of Biogas of Pasar Induk Buah dan Sayuran Gemah Ripah, Gamping, Sleman, Yogyakarta. This research was to obtain the production cost and scale up capacities for each biogas purification method. The sensitivity analysis was conducted to study the influence of gas composition ranged at 30-70% CH4 toward the flow of absorbent to gas ratio, the price of waste changed from decreasing 100% up to increasing 100% and the finance changed ranged at 0-15% to the change of production cost.The result showed that water scrubber was the cheapest method for scrubbing impurities. The production cost of scale up capacities compared to the price of pipeline quality natural gas which ranged at 6-10 US$/MMBtu. The minimum capacity of economical biogas purification methods was 100 tons waste/day. The influence of gas composition ranged at 30-70% of CH4 produced the L/G value change in the absorber column ranged at 0,005-0,025; the influence of waste price from decreasing and up to increasing 100% and finances from 0-15% produced the production cost change ranged at 3-8 US$/MMBtu and 2-14 US$/MMBtu respectively.
Life cycle assessment pabrik semen PT Holcim Indonesia Tbk. pabrik Cilacap: komparasi antara bahan bakar batubara dengan biomassa Taufan Ratri Harjanto; Moh. Fahrurrozi; I Made Bendiyasa
Jurnal Rekayasa Proses Vol 6 No 2 (2012): Volume 6, Number 2, 2012
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.4696

Abstract

Holcim Indonesia Tbk. Cilacap having capacity of 2.6 million ton/year uses rice husk as alternative fuels. The utilization of the rice husk will effect the environment. The aim of the study is to evaluate the effects of biomass utilization to environment using life cycle assessment (LCA) method.The “cradle to gate” approach was used to evaluate four scenarios of different fuel combinations: (1) 100% coal, (2) mixed fuel of 90% coal and 10% biomass, (3) mixed fuel of 50% coal and 50% biomass, (4) 100% biomass as primary fuels in the kiln for 1000 kg cement. Evaluation of environment impact related to each scenario was using ISO 14040 (2006) that consists of: (1) goal definition and scoping, (2) inventory analysis, (3) impact assessment, and (4) interpretation.Results showed by contribution analysis, the scenario 1, 2, 3, and 4, give 2.78 x10-1 Pt, 2.24 x10-1Pt, 1.57 x10-1Pt, and 8.50 x10-2 Pt respectively. It was also found that the global warming, respiratory inorganic and resources give significant impacts to the environment. It is suggested to replace silica tranportation using train, to utilize miscanthus giganteus and to grow plants or reforestry.
Integrasi proses elektrokoagulasi-elektrooksidasi sebagai alternatif dalam pengolahan limbah cair batik zat warna naftol Fikry Nashrullah K; Muslikhin Hidayat; Moh. Fahrurrozi
Jurnal Rekayasa Proses Vol 10 No 1 (2016): Volume 10, Number 1, 2016
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.34425

Abstract

The production of batik produces wastewater which contains mixture of complex organic macromolecules. In this study, a sequential process of electrocoagulation-electrooxidation (EC-EO) using electrodes of aluminium-graphite and PbO2-graphite was proposed as an alternative method for treating wastewater of naphthol from batik dyeing process. The effects of parameter of current density of in the range of 3.7-7.90 mA/cm2, and the effect of electrical voltage to the decrease of color intensity. The electrocoagulation-electrooxidation method was carried out in a batch reactor with a capacity of 1.3 L, where the first 20 minutes is the electrocoagulation process and the next 100 minutes is the electrooxidation process. The samples were drawn at 10, 20, 40, 60, 80, 100 and 120 minutes and their color intensity was analyzed using spectrophotometric method. The results showed that the highest decreased value was at 99,78% at the current density (7,53 mA/cm2) during 120 minutes with electricity consumption 14,40 kWh/m3. The higher the density of the current, the greater the decrease value of color intensity in the liquid naphthol waste.
Mathematical modelling and simulation of hydrotropic delignification Indah Hartati; Wahyudi Budi Sediawan; Hary Sulistyo; Muhammad Mufti Azis; Moh Fahrurrozi
Jurnal Rekayasa Proses Vol 13 No 1 (2019): Volume 13, Number 1, 2019
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.42364

Abstract

Delignification is a fundamental step in bio-refinery for lignocellulose feedstock processing. Hydrotropic delignification is considered as a promising alternative compared to other conventional delignification processes due to the use of mild chemicals. In this paper, a quantitative description of hydrotropic delignification for a cylindrical biomass particle is presented by using fundamental concepts of chemical kinetics and transport processes. The development of hydrotropic delignification model was based on following assumptions: i) lignin in the biomass is immobile, ii) delignification is considered as a simultaneous process which involves intra-particle diffusion of hydrotropic agent followed by second order reaction for lignin and hydrotropic chemical, as well as intra-particle product diffusion. Finite difference approximation was applied to solve the resulting partial and ordinary differential equations. The simulation results of the proposed model may describe the concentration profiles of lignin, hydrotropic agent and soluble product distributions in a cylindrical solid particle as a function of radial position and time. In addition, the model could also predict the concentration of hydrotropic agent and soluble product in the liquid phase as well as the yield and conversion as a function of time. A local sensitivity analysis method using one factor at a time (OFAT), has been applied to investigate the influence of particle size and hydrotropic agent concentration to the yield and conversion of the hydrotropic delignification model. Validation of the proposed model was conducted by comparing the numerical results with an analytical solution for a simple case diffusion in cylinder with constant surface concentration and in the absence of chemical reaction. The validation result showed that the hydrotropic delignification model was in good agreement with the analytical solution.
Analysis method of black liquor pyrolysis and gasification using deconvolution technique to obtain the real time gas production profile Joko Wintoko; Suryo Purwono; Moh. Fahrurrozi; Bambang Soehendro
Jurnal Rekayasa Proses Vol 14 No 1 (2020): Volume 14, Number 1, 2020
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.56152

Abstract

In thermal reaction experiments, e.g., pyrolysis, combustion, and gasification, the gas released from the reaction can be analyzed in gas measuring instruments. There will be some time delay due to the relatively long gas travel from the reactor to the analyzers. Besides, there can be some time lag in the gas measuring instrument. Gas dispersion may furthermore occur and thus alter the gas concentration profile. The observed gas concentration, therefore, can be very different from the original gaseous reaction products profile. A mathematical procedure called deconvolution technique will be used to get the original gaseous reaction products concentrations profile. The deconvolution technique is based on the assumption that original data have been altered by a transfer function to yield observed data. By the deconvolution techniques, the transfer function for each data set will be calculated and then can be used to compute the original data. In this study, the deconvolution technique was applied to the concentration profile of gaseous products from black liquor pyrolysis and gasification reactions measured by gas analyzers instruments to obtain the real-time gas concentration profile during the processes. Tracer gases are injected in the reactor To facilitate the deconvolution calculation, and their concentration profiles observed in the measuring instruments are recorded. Gaseous products that are analyzed are CO2, CO, CH4, SO2, and H2S. This technique can successfully provide the real-time gas production concentration profile from the black liquor pyrolysis and gasification reaction.