Lau Kok Keong

Thermo Physical Analysis of 2-amino-2-methyl-1-propanol Solvent for Carbon Dioxide Removal

Removal of acid gases such as carbon dioxide (CO2) is normally carried out by aqueous solutions of alkanolamines. The traditional amines used for acid gas removal include; mono-ethanolamine (MEA), di-ethanolamine (DEA) and N-methyldiethanolamine (MDEA). There is a need to investigate new solvents to minimize the carbon emissions since the traditional amines have low CO2 loading capacity and require high energy for regeneration. Recently, a new class of amines, sterically hindered amines is identified as one of the potential solvent for acid gas removal due to their relatively higher CO2 absorption capacity, low heat of regeneration and higher values of rate constant. One of the identified solvent that has potential for commercialization is sterically hindered amine known as 2-amino-2-methyl-1-propoanol (AMP). The investigation of thermophysical properties of this solvent is essential in the design and optimization for smooth operation of acid gas removal process. The density, viscosity, surface tension and refractive index are the most important physical properties for this purpose which is presented in this paper. These properties of aqueous solutions of 2-amino-2-methyl-1propanol (AMP) are investigated over the industrially important temperature range of 298.15 K to 333.15 K. The thermal analysis of aqueous solutions was also carried out using TGA (Thermal gravity analyzer) with the heating rate of 10 °C·min under nitrogen (N2) environment in order to investigate the thermal stability of the solvent. All the investigated properties are correlated as a function of temperature for ease of usage in the design of acid gas removal system. The correlated and measured data are in good agreement.

Methods Comparison for the Synthesis of Deca-dodecasil 3 Rhombohedral (DDR3) Zeolite Crystals

In the present work, DDR3 zeolite crystals were synthesized using two different methods. The silica sources used to synthesize DDR3 crystals were tetramethoxysilane (TMOS) and Ludox-40. The resultant samples were characterized using X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM). The XRD results showed that the peaks representing DDR3 structure were not obtained for the sample synthesized in 5 days at room temperature with ultrasonic pre-treatment of 3h using Ludox-40 as silica source. On the other hand, the XRD pattern obtained for the sample synthesized in 25 days at 160 o C using TMOS as a silica source were similar with the XRD peaks reported in the literature. From these results, it can be concluded that the synthesis conditions of 25 days at 160 o C using TMOS as silica source were the favorable conditions in obtaining DDR3 crystal structure.

Solubility of carbon dioxide in aqueous solutions of Piperazine (PZ) at elevated pressures

The solubility of carbon dioxide (CO2) was measured in (0.2, 0.4, 0.6 & 1.2) molars of aqueous solutions of Piperazine (PZ) at three temperatures (30, 40 and 60) °C. The measurements were made over the pressure range of 5 to 60 bar. The results are presented as a function of pressure. It has been found that PZ gives significantly higher CO2 loadings at higher pressures. The influence of pressure on solubility is found to be positive. However, solubility decreases with the increase of temperature and PZ concentration.

Assessing the significance of rate and time pulse spraying in top spray granulation of urea fertilizer using Taguchi Method

Studies in urea granulation process using Top Spray Fluidized Bed Granulator (TSFBG) is still limited and requires in-depth research about the effectiveness and influence of droplets to the formation of urea granule (UG). Rate and time interval of spraying technique (Pulse) significantly influence the physical properties of urea granules. Cassava starch dissolves in water was selected as the binder released at various time interval to observe impact of spray droplet on UG size formation. Using Taguchi Method, the study had identified three leading factors contributed to the formation of droplet size namely volume of binder (VOB), time pulse of spraying (TPS) and spraying rate (SR). These factors were then evaluated in terms of the influence on response as signal-to-noise analysis (S/N ratios) from Taguchi to validate UG size in range 2 mm to 4 mm from screening process with respect to the actual experimental data. These results were useful for future experiment reference to determine pressure drop and surface contact during interaction between droplet and urea powder particles using TSFBG to obtain uniform UG size and smooth surface layer with reasonable hardness.

Novel Approach and Setup for Multi Component Mixtures Separation and Analysis at Offshore Conditions

The precious demand not in the push away and broad off from receive forward developed technology approaches place the hand almost several lacks of warns and in-needed developed technique and techniques for greater than before contract and analysis for several issues, no complimentary and talk to studies within the literature describe the system comes in multi component and dual phase particularly for those that ought to be investigated at offshore conditions, the novel technique and setup has been created for such scope, the recently developed set up has the flexibility to analyses the sorption isotherms and kinetic for multi component and dual phase mixtures (gas and vapor) at offshore conditions in term of temperature up to 150 oC and pressure up to 150 bar. Additionally to the pretreatment that would be finished to the sorbents used at temperatures up to 400 oC and vacuumed pressure. The primer experiments are done using 13 X zeolites for the sorption of pure CO2 and binary mixtures (CO2 and CH4) at elevated conditions.

Application of Response Surface Methodology to Investigate CO2 Absorption Column Temperature Rise

This study aims to investigate the impact of process parameters to the column temperature rise during the absorption process using response surface methodology (RSM). The parameters studied were liquid temperature, column pressure, CO2 inlet concentration and gas flow rate. While all the factors studied had significant impact to the quadratic model for the temperature rise, the magnitude of temperature rise was more obvious with the variation of column pressure and CO2 inlet concentration. The column temperature rise was found to be high when the liquid temperature, column pressure and CO2 inlet concentration were high. Similar behavior of high column temperature rise was also observed when the gas flow rate was low.

Preparation and Characterization of Polysulfone Membrane for Gas Separation

Symmetric and asymmetric polysulfone membranes were fabricated using different of solvents; N-methyl-pyrrolidone (NMP), Tetrahydrofuran (THF) and Dimethylacetamide (DMAC) at different polymer concentration (15 and 20%) to study the influence of varying type of solvents and polymer concentration in membrane fabrication. The membranes were characterized using Field Emission Scanning Electron Microscopy (FESEM), Thermogravimetric Analyzer (TGA), Universal Testing Machine (UTM) and Fourier Transform Infra-Red (FTIR).The results disclosed that the symmetric, higher polymer concentration membrane contributed to better thermal and mechanical stabilities. PSF/THF membrane showed good mechanical strength while PSF/DMAC membrane illustrated great thermal stability. 20% of polymer concentration and PSF/THF membrane led to the thicker skin layer and dense structure formation.

Simulation of Hydrodynamics and Reaction Behavior in an Industrial RFCC Riser

A 2D axi-symmetric, steady state and pressure-based model for the riser of an industrial RFCC unit was developed with ANSYS FLUENT in workbench 13.0. The EulerianEulerian approach was applied to simulate the flow behavior of the two phases and the catalytic cracking reactions. The k-ε gassolid turbulent flow per phase model was used, and the particle-level fluctuations are modeled in the framework of the kinetic theory of granular flow. Two different drag models were used separately to simulate the gas solid interaction in the riser fluidized bed. The 14-lump kinetic model was chosen to describe the complex catalytic cracking of the heavy residual feed stock. The particle volume fraction, velocity and temperature profiles, as well as product yields in the riser were analyzed and validated with results from open literature and the industrial RFCC plant data.