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Reactive distillation (RD) holds promise for process intensification in biodiesel production since it integrates reaction and separation. It simplifies the process and enhances the conversion of the equilibrium limited reactions. To ensure the stability in RD operation, sensitivity study and process control simulation are necessary. In this work, RD was employed for free fatty acid (FFA) esterification of mixed non edible oils in biodiesel synthesis. Non edible oils used were waste cooking oil, crude jatropha oil, and crude nyamplung oil (Calophyllum inophyllum L). Simulation was conducted using ASPEN Plus V8.8. Sensitivity study was carried out to determine the effects of the operating condition alteration. A dynamic simulation was performed as a Proportional-Integral-Derivative (PID) controller tuning. It was revealed that the highest FFA conversion was 85%, achieved at the feed stage of 7, distillate rate of 0.22 kmol/hr, and oil to methanol molar ratio of 1:5. Level, pressure and temperature controls were installed in RD. Then, a dynamic simulation was applied as a PID controller tuning. Three different controller tuning methods, viz. Ziegler-Nichols, Cohen-Coon, and Internal Model Control, were studied. The best PID parameter was obtained by using Cohen-Coon method which provided fastest rise time, lowest settling time and lowest overshoot.

A large number of bifunctional ionic liquid extractant with ammonium-based have been formulated to separate and extract rare earth (RE) ions with better extraction efficiencies and selectivities co...

Oleic acid is a mono-unsaturated fatty acid that can be found abundantly in various vegetable oils and potentially attractive to be used as raw material for epoxide chemical. In-situ epoxidation of oleic acid was conducted in batch reactor using peroxy-formic at 30-60°C. Pseudo-steady-state-hypothesis (PSSH) was applied to develop the kinetic model. Heterogeneous liquid-liquid system was chosen and four models which emphasized on the ring opening agent (ROA) and reversibility of the epoxidation reaction were proposed. It has been suggested that reversible model is well suited to represent the experimental data. Activation energy obtained from Arrhenius equation is in the range of 40-195 kJ/mol.

In general, the multiple-input-multiple-output (MIMO) system is the main method of process control in industry. However, the interaction between variables in the process is a challenge when designing controllers for the system. Strong interaction worsens system performance. Inverted decoupling plays an important role in reducing interaction in the process. Internal model control (IMC) is the controller used in this research. A one degree of freedom (1DoF) IMC controller is only able to provide a good response to set-point tracking, and has a slow response to disturbance rejection. Therefore, a controller that has a good response to set-point tracking and disturbance rejection is a two degrees of freedom (2DoF) IMC. The tuning method uses maximum peak gain margin (Mp-GM) stability criteria based on the uncertainty model. In this study, a reduction in interaction was realized by the addition of inverted decoupling to the 2DoF IMC control scheme. The Wardle & Wood and Wood & Berry column distillation models are given as illustrative examples to demonstrate the performance of the inverted decoupling 2DoF IMC control scheme. A comparison is made of the IAE values of 1DoF IMC, 2DoF IMC, decoupling 2DoF IMC, and inverted decoupling 2DoF IMC, with inverted decoupling 2DoF IMC showing the lowest IAE value.

The changing capacity of gold adsorption with new and reuse resins in hydro metallurgical process was studied with Purolite and Dowex Minix resin. Fresh resin or regenerated resin is put into 1000 ml of gold mother solution and mixed, and the samples are taken for every 10 min. As a results adsorption capacity for fresh Purolite resin logarithmically increased in 70 min to reach 95.3% capacity and 34.3% regenerated Purolite resin adsorption capacity. Adsorption capacity for fresh Minix resin was 95.7% capacity and barren Minix resin adsorption capacity was 71.9%. Resin Metals loaded after elution process showed Dowex Minix resin had higher Au concentration and Au selectivity in adsorption process than Purolite resin. The total metal adsorption capacity of Purolite was higher than the Dowex Minix resin. Purolite resin seemingly has faster loading rates compared to Dowex Minix resin. Purolite resin seems stronger base resin, higher load, and more difficult for elute than Dowex Minix.

Oleic acid is a mono-unsaturated fatty acid that can be found abundantly in various vegetable oils and potentially attractive to be used as raw material for epoxide chemical. In-situ epoxidation of oleic acid was conducted in batch reactor using peroxy-formic at 30-60°C. Pseudo-steady-state-hypothesis (PSSH) was applied to develop the kinetic model. Heterogeneous liquid-liquid system was chosen and four models which emphasized on the ring opening agent (ROA) and reversibility of the epoxidation reaction were proposed. It has been suggested that reversible model is well suited to represent the experimental data. Activation energy obtained from Arrhenius equation is in the range of 40-195 kJ/mol.

An example of sintered inert ceramic is ceramic balls as catalyst support media. The composition of the ceramic is regulated by Universal Oil Products (UOP) standard. The requirement of the chemical composition will therefore determine the range of sintering temperature, number of phases or crystal during sintering, and the weight percent of starting materials. The weight percent of starting materials becomes important in order to fulfil the UOP requirement since all of the materials are stable raw materials and can be found directly from nature. This study is to design how to have the starting material composition and sintering temperature to fulfil the standards. One example of inert ceramic ball design is illustrated at the end of this paper.

This paper studied the use of bifunctional ionic liquid as an extractant to extract and separate Sm-Eu-Gd mixed solutions. The extractant combined the conventional extractant di-(2-ethyl hexyl) phosphate (P204) with ionic liquid Aliquat 336 (A336) through acid/base neutralization method. This work explored the effect of extraction medium (chloride, sulphate and nitrate), acid concentration (1.5-5.0 M) and organic to aqueous phase ratio (1:1, 3:2, 7:3, 4:1, 9:1) to determine the separation factor of each metals. Based on the results, Sm(III) showed the highest separation factor of total solute (βSm/total-Sm=2.81) in the nitrate medium with the acid concentration of 3.0M and organic to aqueous phase ratio of 4:1. Sm(III) was chosen to be separated in the first stage of extraction from the Sm-Eu-Gd mixed solution. In the second stage, the optimized condition to separate the remaining Eu-Gd mixed solution into individual metal was also in the nitrate medium with organic to aqueous phase ratio of 3:2, except with lower acid concentration, 2.0M. This work shows that [A336][P204] is an impeccable extractant candidate for an improved and environmental friendly to separate Sm-Eu-Gd in both laboratory and industrial application.

The solvent is a liquid that can dissolve or extract specific materials. Solvents are needed for most chemical transformations to increase contact between reagents and catalysts. It also holds an important role in many studies, industrial chemical processes, coatings, and formulations of consumer products, however, most of the hydrocarbon-based solvents based still contain high aromatic content of benzene, toluene, and xylene which are carcinogenic chemicals. The separation of aromatic hydrocarbons from a mixture of C4-C10 aliphatic hydrocarbons is a complex process, due to its close boiling points and some combinations can form azeotropes. The general distillation process is not the right choice for the separation of aromatic hydrocarbons from a mixture of C4-C10 aliphatic hydrocarbons. Possible processes are liquid-liquid extraction, extractive distillation, and azeotropic distillation. In this study, extractive distillation using ASPEN Plus was performed to simulate the process. The crude feed composition used contains 77.13% aromatic compounds so that the separation technology used uses the extractive distillation process using sulfolane as a solvent. The variables used are the ratio of the crude feed to sulfolane (1:10, 1:15, 1:20), the number of stages (30, 40, 50), feed stage (15,20,25). Based on the simulation results, the best result was obtained by using the ratio of the crude feed to sulfolane of 1:10, with the number of stages 30, and the feed stage on the 25th stage.

Extraction of rare earth using ionic liquid as extractant become an alternative practice to replace the common volatile organic solvents in recent years. In general, the work to extract rare earth element, require a large number of extraction stage, and different extractant used resulted in different number of extraction needed. Therefore an analysis on the theoretical number of stages is necessary prior to laboratory work. This study was designed to compare between the number of extraction stages required by 2-ethylhexyl phosphoric acid mono 2-the ester (P204), a common rare earth extractant with a bifunctional ionic liquid, and [A336][P204] in a counter-current extraction process for the separation of Sm in Sm-Eu-Gd mixed solution. The value of the separation factor (β) of both extractants, was obtained from the experimental work, while other process parameters were calculated using the counter-current theory developed by Xu Guangxian. Extraction of Sm using [A336] [P204] was optimum in 3.0 M of nitric acid, with organic to aqueous (O/A) ratio of 4:1, while the optimum condition for P204 was when the medium was 2.0 M of hydrochloric acid and 7:3 of O/A ratio. The β value for the optimized condition for P204 was lower compared to the condition for [A336][P204] at β:1.93 and β:2.81, respectively. To derive an optimum extraction condition to calculate the number of extraction stage, target purity and recovery ratio were set to 99.9% and 90%, respectively, for both extractants. As a result, [A336][P204] was able to reduce the number of extraction stage by 5 compared to P204. The result indicated that [A336][P204] is preferable over P204 from the viewpoint of economic efficiency.

Growth of electricity demand is rapidly increasing. Several method to supply electricity such as utilizing renewable energy has been used. Nuclear energy is still the best choice to produce electricity. Instead of using uranium as a fuel, utilization of thorium as a nuclear power plant fuel has been investigated since 1950. Thorium is much safer than uranium since it does not produce hazardous by product which can be used as an explosive material. Thorium can be found widely in Indonesia together with uranium and many other rare earth material such as lanthanides group. Separation is needed before thorium can be used as a fuel. In this article, preliminary study of thorium separation from monazite mineral has been conducted. The end product of this study is a plant design for thorium separation process. This study used secondary data which has been lab scale experimental. The data was then predicted by using mathematical model, calculated data were then compared to the experimental data. The model used in this study was in accordance with the experimental data, where R2 for thorium, uranium and rare earth element are 0.9591, 0.7591 and 0.9889 respectively. The developed model in this study then can be used for thorium separation process modelling using METSIM.

Generally, chemical industry processes have the characteristics of a multi-variable process, and influenced by the disturbances which may be detrimental to the process. Quadruple tank process is a simple prototype which represents the complicated multivariable dynamic process. However, this system originally doesn’t have time delay that always occure in industrial process. Thus, this study modify the system by adding heater in tank I and tank 2. In addition, interaction between tank I and tank 2 also tank 3 and tank 4 was modified [2]. Two controllers are implemented to maintain level and temperature of tank I and tank 2 i.e. PI-PID and 2DoF IMC. The PI-PID controller parameters are determined by Ziegler-Nichols tuning method which detuned by Mc Avoy method and BLT method, while the 2DoF IMC controller parameter is determined by MP-GM method. In the minimum phase, based on the value of IAE, the PI controller with detuning Mc Avoy better than the 2DoF-IMC in controlling levels and 2DoF-IMC better than cont...

Main function of oil production facility is to separate oil well stream into three phases i.e. oil, gas and water. A vessel called three phase separator is used for this purpose, commonly in horizontal arrangement. In order to optimize the process, an accurate model for horizontal three phase separator (HTPS) is needed. Computational Fluid Dynamics (CFD) is a mathematical tool capable of simulating a wide range of fluid flows. HTPS dimensions used in this simulation were taken from one of oil and gas company in Indonesia. The CFD simulation used in this study is based on volume of fluid and k-e turbulence models. Gas outlet was assumed using porous media zone model with fluid porosity 0.99. Simulation result displayed concentration and velocity distribution for each component inside HTPS. The result of concentration distribution shows that the region of fluid divided into upper region and lower region. The lower region major component were water and upper region mainly consist of gas and oil. The contour of concentration distribution indicated a good separation process with distribution of water flow rate at the outlet of water, oil, and gas respectively are 405,67; 115,65; and 172.01 lb/min

Excess molar volume and viscosities are one of the important fundamental data for the design and optimization of chemical process. In this study, excess molar volume and viscosities of 1,4 Dioxane with two hydrocarbons Bromobenzene and Ethyl benzene have been measured over the entire range of composition at (303.15, 308.15, and 313.15) K. From experimentations excess volumes, VE, and deviations in viscosities, Δη, are calculated. The calculated excess volumes, VE and deviations in viscosities, Δη exhibited positive and negative values respectively over the whole range of composition in both binary systems. The Redlich-Kister Model was used to correlate excess volumes, VE, and deviations in viscosities, Δη, to derive the binary coefficients and standard deviations of these systems. The fitted outcomes and the calculated data clearly indicated that weak interactions present in two mixtures. It is mainly because of number and position of methyl groups exist in these aromatic hydrocarbons. It can conclude that the experimental values are predicted well by the Redlich-Kister Model with high degree of precision.

Nonconventional column/rectifier configuration is the new alternate design for the sequence multicomponent separation of three or more products. It can accomplish an efficient energy. There are two columns, the first is the rectifier and the second is the main, the vapor sidestream is taken out from the location under the feed tray of the main column then fed to the rectifier column and the liquid that from the bottom of the rectifier column is turned back to the main column. In order to completely understand the dynamic behavior of complex process of this configuration, process dynamic and control of it has to be studied intensively. The implementation of it is demethanizer and deethanizer column. The configuration has been simulated for dynamic by using Aspen Hysys v10.0. The results show that the graph of rejecting disturbance from all controllers of the main column need more attention especially for inventory control i.e. level controller for reflux drum, sump level reboiler and pressure controller for condenser. The overshoot for level controller of reflux drum of main column is 10% from set points. The better algorithm of tuning is required. The results of this studied could provide guidance for composition controller of this configuration.

There are many uses of agarwood trees in a number of countries around the world. However, lack in extractionprocess efficiency was affected to the lower product quality and oil yield. Therefore, this research was aimed toinvestigate the effect of pre-treatment techniques of soaking with water and soaking with three fungi onagarwood oil yield. The oils produced were compared with industrial samples. Analysis of chemical compoundsis done by using Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-MassSpectrometry (GC-MS). As a result, the sample treated with fungi Phanerochaete chrysosporium achieved thehighest average oil yields of 0.58% with content of 80.13% of total chemical compounds compared to sampletreated with water only consist of 0.27% oil yield and 72.58% of total chemical compounds was detected. Thesample soak with fungi is more advantageous than soak with water in terms of oil productivity, energy savingand efficiency process. The main component present in all parameter studied were epoxybulnesene (1.64%-7.54%), tetradecanal (1.02%-6.10%), agarospirol (0.29%-1.34%), bulnesol (0.59%-8.07%), selina-3,11-dien-9-ol (1.10%-4.02%), oxo-agarospirol (1.12%-10.80%) and eudesmol (0.19%-9.17%).