Bawadi Abdullah

Composition Prediction of a Debutanizer Column using Equation Based Artificial Neural Network Model

Debutanizer column is an important unit operation in petroleum refining industries. The design of online composition prediction by using neural network will help improve product quality monitoring in an oil refinery industry by predicting the top and bottom composition of n-butane simultaneously and accurately for the column. The single dynamic neural network model can be used and designed to overcome the delay introduced by lab sampling and can be also suitable for monitoring purposes. The objective of this work is to investigate and implement an artificial neural network (ANN) for composition prediction of the top and bottom product of a distillation column simultaneously. The major contribution of the current work is to develop these composition predictions of n-butane by using equation based neural network (NN) models. The composition predictions using this method is compared with partial least square (PLS) and regression analysis (RA) methods to show its superiority over these other conventional methods. Based on statistical analysis, the results indicate that neural network equation, which is more robust in nature, predicts better than the PLS equation and RA equation based methods.

Real-time monitoring and measurement of wax deposition in pipelines via non-invasive electrical capacitance tomography

Tomographic analysis of the behavior of waxy crude oil in pipelines is important to permit appropriate corrective actions to be taken to remediate the wax deposit layer before pipelines are entirely plugged. In this study, a non-invasive/non-intrusive electrical capacitance tomography (ECT) system has been applied to provide real-time visualization of the formation of paraffin waxes and to measure the amount of wax fraction from the Malay Basin waxy crude oil sample under the static condition. Analogous expressions to estimate the wax fraction of the waxy crude oil across the temperatures range of 30–50 °C was obtained by using Otsus and Kuos threshold algorithms. Otsus method suggested that the wax fraction can be estimated by the correlation coefficient while Kuos method provides a similar correlation with . These correlations show good agreements with the results which are obtained from the conventional weighting method. This study suggested that Kuos threshold algorithm is more promising when integrated into the ECT system compared to Otsus algorithm because the former provides higher accuracy wax fraction measurement results below the wax appearance temperature for waxy crude oil. This study is significant because it serves as a preliminary investigation for the application of ECT in the oil and gas industry for online measurement and detection of wax fraction without causing disturbance to the process flow.

Upgrading of bio-oil from palm kernel shell by catalytic cracking in the presence of HZSM-5

ABSTRACT Upgrading of bio-oil extracted from palm kernel shell (PKS) was performed using a lab-scale fixed-bed reactor with HZSM-5 as a catalyst. The catalytic cracking was carried out at optimized conditions: 0.3-MPa pressure, temperature of 500°C, and oil to catalyst ratio of 1:5. One of the challenges in upgrading bio-oil by catalytic cracking is deactivation of catalyst due to coke formation on catalyst surface. To overcome coke deposition, the upgrading process was carried out at 0.3-MPa pressure. Characterization of raw and upgraded bio-oil obtained through catalytic cracking was discussed in detail, indicating improvement in its physical properties. The distribution of products after cracking of bio-oil includes 58.89 wt% of organic liquid product, 15.63 wt% of aqueous fraction, 7.84 wt% of coke, and 17.64 wt% of gases. The degree of deoxygenation and calorific value of organic liquid product is 43.74% and 31.65 MJ/kg respectively. Organic liquid product obtained comprises 17.55% of hydrocarbons within the gasoline range. Hence, HZSM-5 proved its effectiveness for upgrading the bio-oil in a continuous mode.

Thermocatalytic decomposition of methane/methanol mixture for hydrogen production: Effect of nickel loadings on alumina support

Hydrogen produced by thermocatalytic decomposition of methane is termed as clean and alternative fuel however high reaction temperature and fast catalyst deactivation limitize the efficiency of this process. In this study nickel based catalyst supported on alumina with various Ni loadings were prepared by impregnation method and employed for TCD of methane/methanol mixture for hydrogen production. Surface area and pore volume were decreased by increasing the amount of nickel loading on alumina. The results revealed that both reaction temperature and nickel loading affected the reaction rates and catalyst deactivation time. Scanning electron microscope (SEM) and Thermogravematric analysis (TGA) were used for characterization of fresh and spent catalyst. Crystalline carbon was formed on the surface of the catalyst and was proved by TGA analysis. Methane yield increased as the reaction temperature was increased but the catalyst deactivation time was decreased as a lot carbon was encapsulated on the surface o...

Influence of Acid and Thermal Treatments on Properties of Carbon Nanotubes

The application of carbon nanotubes as a catalyst support has received considerable attention recently. The influence of acid and thermal treatments on the properties of multi-walled carbon nanotubes (MWCNTs) is presented in this paper. MWCNTs were treated with 65 wt% HNO3 at the 120 °C for 14 h in order to open the caps and introduce functional groups on the MWCNTs. Then thermal treatment was carried out at 600, 700, 800, 900 °C for 3 h in flowing Ar gas in a tubular furnace. The MWCNTs were characterized by N2- adsorption, FESEM and Raman spectroscopy. The thermal treatment resulted in slight morphological changes of the MWCNTs. The acid and thermal treatments also increased the BET surface areas and pore volumes of the MWCNTs.

Production of Biofuel via Hydrogenation of Lignin from Biomass

Historically, humans have been harnessing biomass as a source of energy since the time they knew to make a fire from woods. Even today, some countries still depend on woods as a main source of energy. Biologically, biomass contains carbon-, hydrogenand oxygen-based matters that unify in a solid material and that are potentially to be converted to fuel. Lignin is one of the components present in lignocellulosic biomass and has been actively examined to be used for biofuel production. Issues arise with the chemical characteristic and rigidity of its structure, which a setback for its viability for biofuel conversion. However, such setbacks have been counteracted with the advances of lignin-based knowledge on its conversion to chemical precursors for biofuel conversion. Recently, investigations on hydrogenation as one of the chemical processes used can be potentially utilised for efficient and viable means for biofuel production.

Hydrogenated microstructure and its hydrogenation properties: a density functional theory study

The relationship between microstructure and hydrogenation properties of the mixed metals has been investigated via different spectroscopic techniques and the density functional theory (DFT). FESEM and TEM analyses demonstrated the nano-grains of Mg2NiH4 and MgH2 on the hydrogenated microstructure of the adsorbents that were confirmed by using XPS analysis technique. SAED pattern of hydrogenated metals attributed the polycrystalline nature of mixed metals and ensured the hydrogenation to Mg2NiH4 and MgH2 compounds. Flower-like rough surface of mixed metals showed high hydrogenation capacity. The density functional theory (DFT) predicted hydrogenation properties; enthalpy and entropy changes of hydrogenated microstructure of MgH2 and Mg2NiH4 are -62.90 kJ/mol, -158 J/molċK and -52.78 kJ/mol, -166 J/molċK, respectively. The investigation corresponds to the hydrogen adsorption feasibility, reversible range hydrogenation thermodynamics, and hydrogen desorption energy of 54.72 kJ/mol. DFT predicted IR band for MgH2 and Mg2NiH4 attributed hydrogen saturation on metal surfaces.

Heavy Metal Removal by Oil Palm Empty Fruit Bunches (OPEFB) Biosorbent

This study developed an effective and economical physical pretreatment of OPEFB to be used as biosorbent for the removal of heavy metal ions such as Cu+2, Zn+2 and Pb2+. The effects of fibres sizes, metal ions concentration (100-1000 ppm), initial pH (4-10) and contact time (20-150 min) were investigated in batch system. Samples were characterized with Atomic Absorption Spectrometry (AAS), Transmission Electron Microscopy (TEM) and Fourier Transmission Infra-red Spectroscopy (FTIR). Results showed pH-dependence adsorption efficiency and increased adsorption with initial metal concentrations where more than 92% adsorption efficiency achieved. We have successfully developed an eco-friendly, low cost adsorbent without any chemical modification or excessive energy disposal.

Synthesis and Characterization of Co/CNTs Catalysts Prepared by Strong Electrostatic Adsorption (SEA) Method

Strong Electrostatic Adsorption (SEA) is an effective method to synthesize and introduce Cobalt nanoparticles on Carbon Nanotubes (CNTs) support. Point of zero charge (PZC) of CNTs and optimum pH, the cobalt uptake versus different pH were investigated. By using the range of characterization methods such as TEM, FESEM and TPR catalyst prepared was studied. TEM and FESEM images indicate well-dispersed cobalt particles on the CNTs support. TPR was proven reduction peak at high temperature (530oC) indicating strong interaction between Cobalt and CNTs support. SEA showed the desired method in preparing supported cobalt catalysts.

Catalytic Cracking of Synthetic Bio-Oil: Kinetic Studies

Kinetic study on the transformation of model compounds of bio-oil into less oxygenated liquid product was performed. A fixed bed continuous reactor was used for the catalytic cracking of bio-oil model compounds at the temperatures of 300°C, 400°C and 500°C under atmospheric pressure. HZSM-5 was used as the catalyst with the oil to catalyst ratio of 15. The kinetic behavior of the catalytic cracking of bio-oil was represented by a 3-lumped model. The kinetic parameters were calculated using an error minimization approach based on least square method. The results indicated that rate of formation for both gaseous products as well as for liquid product (LP) increased when the temperature increased. The activation energy for liquid product was higher compared to that for gaseous product. The order of reaction was in a fraction form which implies the complex nature of the cracking reaction.