Intermolecular Interaction of Monoethanolamine, Diethanolamine, Methyl diethanolamine, 2-Amino-2-methyl-1-propanol and Piperazine Amines in Absorption Process to Capture CO2 using Molecular Dynamic Simulation Approach

Many active researches struggle to identify a solution towards problem of effect excessive CO2 emission in atmosphere. Global warming effect happen when there has excess of CO2 percentage in atmosphere. Amine-based absorption process technology is selected in this work because their efficiency to capture CO2 up to 90%. The aim of this paper is to study intermolecular interaction of MEA, DEA, MDEA, AMP and PZ amines based absorption process to capture CO2 using molecular dynamic (MD) simulation. MD simulation was run under condition 313K and 1 atm. It used NVE ensemble at 200ps and NVT ensemble at 1ns. The results were interpreted in term of intermolecular interaction by using Radial Distribution Function (RDF) analysis. It was found that AMP solvent shows the highest tendency to make intermolecular interaction with H2O and CO2 compared to MEA, DEA, MDEA and PZ. MDEA has the weakest intermolecular interaction with CO2 among others. Thus it is required that MDEA to blend with promoter or other amine for enhance the reaction with CO2. The blend of conventional amine i.e. MEA, DEA and MDEA with activator amine is expecting to increase CO2 absorption capacity and reduce heat regeneration requirement

Simulation of leaching process of gold by cyanidation

This paper presents a simulation study of leaching process of gold by using HSC Chemistry software (HSC). Cynide (NaCN) has been used to recover gold from gold bearing ores since 1890’s and until today it still playing an important role in the beneficiation process of the gold. This work aims to develop a simulation process model of this solid-liquid leaching process by using cyanide solvent for the dissolution of gold by using HSC simulator. The simulation of the leaching process was carried out in a continuous steady-state condition. The results from this simulation were compared with other researcher which employed Aspen Plus and it shows very good agreement with very small error (less than 1.5%). A case study was carried out using the developed process model where hydrochloric acid (HCl) was used as solvent in order to recover the gold from the ores. The results from the case study show that the chlorination process gives higher amount of gold (Au) dissolved in the solvent compared to cyanidation process. Another case study was carried out in order to study the effect of different concentration of Au in ores and the effect of different concentration of solvent as a leaching reagent. As a conclusion, the develop process model provide an effective means for studying the solid liquid leaching process in the future

Sensitivity analysis of leaching process on rare earth elements by using metsim software

Leaching is part of the hydrometallurgical treatment in the separation of rare earth elements (REEs). The increase of demand for REEs in the world but its limited supply caused by the separation process that has negative environmental impact, as well as high costs of laboratory work, the alternative method to study on the extraction of these resources are urgently needed. This can be done through simulation study that eliminates the number of experiment that needs to be carried out. In this work, a sensitivity analysis of the leaching process for light rare earth elements (LREEs); Lanthanum (La) and Neodymium (Nd) from monazite concentrate was carried out by employing a software called METSIM which is able to model metallurgical processes. METSIM software is also able to calculate mass and heat balance of complicated hydrometallurgy processes and furthermore, its function has been expanded to involved chemical reactions, process control and equipment sizing. The simulation of the digestion and the leaching process was run and compared with experimental work from the literature, which aimed to optimize the leaching process. Leaching is an extraction process of a substance from a solid material that is dissolved in a liquid. In this study, the leaching process is modelled as a two-steps process, in which the first step is the digestion process, followed by the actual leaching process. The monazite concentrate is made strong bonds as REEs oxide, therefore, they are not soluble in water before leaching process. For the digestion process, the monazite concentrate was mixed with sulfuric acid (H2SO4) in the digestion reactor. The precipitates which contain leachate was then mixed with deionised water in the leaching reactor to increase the solubility of La and Nd. The reaction equations for the digestion reactor are as shown in Equations (1) and (2), while for the leaching reactor are shown by Equations (3) and (4) as follows

Smart home aquaponic system monitoring and control with internet of things using mobile application

Food security has been a recurrent concern for numerous nations, including Malaysia. Climate change and population growth exacerbate this issue by increasing necessity food. In past few years, aquaponics has proven beneficial for fish and plant production, based on the idea that if every household can generate its own fish and plants, the nation's overall food consumption will reduce. The suggested smart house aquaponics system comprises an assortment of internet-connected sensors, actuators, and ESP32 microcontrollers that continuously monitor, adjust, and record the water and air quality of the fish tank. The Internet of Things (IoT) mobile application feature can alert the user in the event of an abnormal system state in terms of maintaining the health and growth of fish and plants. The Internet of Things (IoT) mobile application feature can alert the user in the event of an abnormal system state in terms of maintaining the health and growth of fish and plants. When the pH and turbidity thresholds are surpassed, the pumps are actuated to either fill or drain the tank. The results show that the design for a smart aquaponics system that can be used in a home is able to monitor and control all the parameters that are needed to cultivate wholesome fish and vegetation

Bacterial adhesion on the titanium and stainless-steel surfaces undergone two different treatment methods: polishing and ultrafast laser treatment

Bacterial adhesion has become a significant problem in many industries causing billions of dollars for its complicated removal treatment and maintenance. In this study, metal surfaces undergone treatment with ultrafast laser with varies power. The microstructure produced on its original surfaces were expected to prevent the adhesion of Escherichia coli (E. coli) ATCC 8739 and Staphylococcus aureus (S. aureus) ATCC 6838. The laser treatment was performed at 380 fs pulse duration, 515 µm central wavelength and a repetition rate of 200 kHz. Stainless steel AISI 316L was treated with an average laser power of 0.04 W (SS-0.04) and 0.11 W (SS-0.11), while Grade 5 titanium alloy was tested with high laser power 0.11 W (T-0.11). The adhesion was observed after 16 hours and the number of adhering bacteria was counted per cm2. The result achieved shows that, increasing the average laser power is leading to an enhanced S. aureus adhesion while E. coli adhesion is reduced which is due to the hydrophobicity interaction and difference in surface texture. Meanwhile, the laser treatment showed significant reduction of the bacterial adhesion on its surface compared to the polished surfaces. Thus, ultrafast laser texturing can be suggested as a promising method to reduce the bacterial adhesion, which reduced the adhesion of >80% for E. coli and >20% for S. aureus

Modeling of Methyl Methacrylate Polymerization Using MATLAB

This paper presents a modeling of methyl methacrylate (MMA) polymerization with toluene in the presence of azo-bi’s-isobutyronitrile (AIBN) using MATLAB. This work aims to optimize the initial concentration of initiator and the reactor temperature to achieve a maximum monomer conversion in minimum batch time. The optimization of solution polymerization of MMA based on the three-stage polymerization model (TSPM) was performed using ode23t solver. The non-linear polymerization kinetics considered the gel, glass and cage effect to obtain a realistic prediction. The predicted reactor and jacket temperature showed a reasonable agreement with the experimental data, where the error is about 2.7 % and 2.3 %, respectively. The results showed that a maximum monomer conversion of 94 % was achieved at 0.126 kgmol m–3 of the initial concentration of AIBN and 346 K of the initial reactor temperature in 8,951 s (2.5 h)

Modelling of leaching process of rare earth element Praseodymium (Pr)

Rare earth elements have their unique physical and chemical properties character that makes them important elements in several of high-tech application. It’s very important to ensure the efficient separation of REE is carried out optimally. In order to achieve this, understanding the fundamental process is essential. Thus the purpose of this study is to relate how the leaching process occurs by using shrinking core model for a better understanding. Rare earth separation process usually passed through a cascade of physical processing steps including beneficiation process. After filtration, leaching solution is passed through a sequence of solvent extraction process with several mixer-settler steps to separate individual or mixed rare earths compounds. The aims of this work are to study and develop a model for leaching process of rare earth elements, Praseodymium (Pr). It was conducted for the purpose of the recovery of the rare earth element from ore. The mathematical model of this work was developed based on the shrinking core model (SCM). The effect of temperature ranging from 30oC – 80oC and concentration (1.5 mol/L – 3 mol/L) of the reagent was carried out in this work. The developed model from this work can be used to predict the recovery of Praseodymium (Pr) from the solid liquid leaching process which can be a good reference for future research

A Review of Rare Earth Mineral Processing Technology

The recent technological advancement has made the rare earth elements (REEs) more significant and they in turn have facilitated the culmination of more new technological applications owing to their unique physical and chemical properties. In this regard, renewable energy applications such as wind turbine and hybrid cars testify to the increasing demands on permanent magnet in the future. Considering such increasing demands on REEs, it is felt necessary to identify alternative producers of REEs outside of China as one of the measures to create a fair competition and control the price on the market. It is worth highlighting that the separation of rare earth can be both complex and challenging owing to similar properties which are shared by them. The purpose of this paper is to comprehensively review and summarize the rare earth processing routes, the mostly employed rare earth separation methods, supply and demand of rare earth around the world and some possible scenarios in rare earth market. This review has critically looked into a few authors recent reviews on six major processes of rare earth processing steps and each step is considered as important to produce both high quality and better quantity of REEs