Khairuddin Md Isa
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Preferred name
Khairuddin Md Isa
Official Name
Md Isa, Khairuddin
Alternative Name
Isa, K. Md
Md Isa, Khairuddin
Md. Isa, Khairuddin
Isa, K. M.
Main Affiliation
Scopus Author ID
36188321600
Researcher ID
Y-7078-2019

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Sulfur dioxide removal by calcium-modified fibrous KCC-1 mesoporous silica: kinetics, thermodynamics, isotherm and mass transfer mechanism

2022-04-01 , Hanif M.A. , Naimah Ibrahim , Khairuddin Md Isa , Umi Fazara Md Ali , Tuan Abdullah T.A. , Jalil A.A.

The removal of sulfur dioxide from industrial flue gas through dry flue gas desulfurization method commonly involves the use of adsorption process with porous sorbent. The efficiency of this process is highly dependent on the adsorption capacity and the adsorption rate of SO2 onto the sorbent materials. The use of KCC-1 mesoporous silica modified with calcium metal additives (Ca/KCC-1) in SO2 adsorption is examined in a fixed bed reactor system. The adsorption capacity of Ca/KCC-1 is found to be critically governed by the reaction temperature and inlet SO2 concentration where low values of both parameters are favorable to achieve the highest adsorption capacity of 3241.94 mg SO2/g sorbent. SO2 molecules are adsorbed on the surface of Ca/KCC-1 by both physisorption and chemisorption processes as assumed by the Avrami kinetic model. Thermodynamic study shows that the process is exothermic and spontaneous in nature, and changes from an ordered stage on the surface of KCC-1 towards an increasingly random stage. The process is well explained by Freundlich isotherm model indicating a slightly heterogeneous process and moderate adsorption capacity. The adsorption stage is limited by film diffusion at the initial stage and by intraparticle diffusion during the transfer of SO2 into the network of pores before adsorption takes place on the active sites.

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The Grease Formulation Using Waste Substances from Palm Oil Refinery and Other Industrial Wastes: A Review

2023-08-01 , Hairunnaja M.A. , Aziz M.A.A. , Bashari N.A.F. , Arifin M.A. , Nedumaran N. , Khairuddin Md Isa , Umi Fazara Md Ali

Many applications use Spent Bleaching Earth (SBE) despite being considered hazardous waste from the palm oil refinery process. Its production increases yearly, similar to waste cooking oil (WCO). The SBE is known as a thickener in grease formulation. The same goes for red gypsum, waste motor oil, stearic acid, and lithium hydroxide monohydrate. They are all considered thickeners but have different durability in protecting base oil in grease. Then, previous studies revealed their performances with side effects detection against the environment and human bodies. Cooking oil is a heat transfer medium for serving foods with higher amounts of unsaturated fatty acids. The number of fatty acids might change after cooking oil consumption and become highly demanded due to the chemical properties of density, viscosity and fatty acids. Nowadays, people lack awareness of the importance of recycling palm oil waste. They intend to dispose of it instead of recycling it for sustainable energy resources. Therefore, this paper will discuss the grease formulation, contaminant available in WCO, its treatment, issues regarding different thickener consumption, treatment against Spent Bleaching Earth (SBE), and propose the safe thickener and additives for future intakes. This study found that adding Fume Silica (F.S.) as a thickener and Molybdenum Disulfide (MoS2) enhanced the grease stability. Further treatment against SBE (remove residue oil) and WCO (metal elements, undesired impurities and water content) is necessary for providing good quality formulated grease.

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Tailoring the properties of calcium modified fibrous mesoporous silica KCC-1 for optimized sulfur dioxide removal

2022-01-01 , Muhammad Adli Hanif , Naimah Ibrahim , Khairuddin Md Isa , Fahmi Muhammad Ridwan , Tuan Abdullah T.A. , Jalil A.A.

Dry regenerative flue gas desulfurization (FGD) is a promising method to tackle industrial issues regarding SO2 emission into the atmosphere due to its sorbent being highly accessible, the lack of water dependency and reduction in waste management. This study examined the feasibility of using fibrous mesoporous silica KCC-1 which has been reported to possess better properties than several other predecessor mesoporous silica as alternative sorbents for dry FGD. Calcium metal was introduced to overcome the lack of active sites available on KCC-1 while simultaneously providing sufficient basicity to counter the increase in acidity brought by SO2 adsorption. Three sorbent modification parameters were analyzed: metal loading (5–15 wt %), calcination temperature (823–973 K) and calcination time (5.5–7 h), and the prepared samples were characterized using BET surface area and pore analyzer, FESEM-EDX, XRD and H2-TPR. The breakthrough experiment was conducted using a lab scale fixed bed reactor system with 1500 ppm SO2/N2 at 200 mL/min. SO2 removal was optimized by sorbent prepared with calcium loading of 5 wt %, calcination temperature of 923 K and calcination time of 6.5 h with adsorption capacity of 3241.94 mg SO2/g KCC-1. The optimized sorbent demonstrated highest surface area, good pore development, high dispersion of calcium metal, appropriate impregnation of calcium oxide which caused only minor distortion to the silica framework of KCC-1. Subjecting the optimized sample to five consecutive regeneration cycles by heating at 773 K while simultaneously flowing N2 gas for an hour shows good regeneration performance with a total final reduction of only 25% from the initial adsorption capacity obtained from a fresh sample.

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Sulfur dioxide removal by mesoporous silica KCC-1 modified with low-coverage metal nitrates

2021-01-01 , Muhammad Adli Hanif , Naimah Ibrahim , Khairuddin Md Isa , Tuan Abdullah T.A. , Abdul Jalil A.

The removal of sulfur dioxide (SO2) from flue gas using fibrous mesoporous silica KCC-1 synthesized via microwave-assisted hydrothermal method was observed. The sorbent was modified by introducing nitrate salts of sodium (Na) and calcium (Ca) at 5 wt. % metal loading via incipient wet impregnation method. The SO2breakthrough experiment was conducted in a vertical quartz-column reactor at atmospheric pressure and temperature of 323 K in the presence of 0.3 % SO2/N2. The SEM micrograph of KCC-1 exhibited a well-defined fibrous morphology consisting of colloidal spheres of 240-1160 nm in diameter. Addition of metal nitrates resulted in the reduction of surface area, total pore volume and minor breakage of the silica framework. The adsorption capacities of all samples were measured at C/C0= 0.5, where the addition of sodium (Na5/KCC-1) and calcium (Ca5/KCC-1) enhanced the removal capacity by 1.88 and 2 times higher than the parent KCC-1 respectively. Even though sodium is expected to achieve better removal capacity due to its higher basicity and dispersion related to the lower crystallite size, its performance ultimately suffered from significant agglomeration of sodium oxide which created pore blockage, subsequently resulting in poor accessibility to the active sites.

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Chemically modified sugarcane bagasse as a potentially low-cost biosorbent for dye removal

2010 , Saiful Azhar Saad , Khairuddin Md Isa , Rohazita Bahari

The use of adsorbent prepared from sugarcane bagasse, an agro waste from sugar industries has been studied as an alternative substitute for activated carbon for the removal of dyes from wastewater. Adsorbents prepared from sugarcane bagasse were successfully used to remove the methyl red (MR) from an aqueous solution in a batch reactor. This study investigates the potential use of sugarcane bagasse, pretreated with phosphoric acid (SBC), for the removal of methyl red from simulated wastewater. Phosphoric acid treated sugarcane bagasse was used to adsorb methyl red at varying dye concentration, adsorbent dosage, pH and contact time. A similar experiment was conducted with commercially available powdered activated carbon (PAC) and untreated sugarcane bagasse (SB) in order to evaluate the performance of SBC. The adsorption efficiency of different adsorbents was in the order PAC > SBC > SB. The initial pH 3 to 6 favoured the adsorption of synthetic dyes by both SBC and SB. This prepared adsorbent was very efficient in decolorized diluted solution. It is proposed that SBC, in a batch or stirred tank reactors could be employed as a low-cost alternative in wastewater treatment for dyes removal.

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Comparative Study of Sulfur Dioxide Removal Using Mesoporous Silica KCC-1 and SBA-15

2022-01-01 , Muhammad Adli Hanif , Naimah Ibrahim , Khairuddin Md Isa , Masitah Hasan , Tuan Abdullah T.A. , Jalil A.A.

Sulfur dioxide (SO2) emitted into the atmosphere by fossil fuel burning in the industries posed significant negative effects on humans and the environment. SO2 removal performance of two mesoporous silica: KCC-1 and SBA-15, are compared through breakthrough experiments on a lab-scale fixed bed reactor. The mesoporous silicas were characterized via nitrogen (N2) adsorption-desorption isotherm and field emission scanning electron microscopy (FESEM). KCC-1 demonstrates characteristics of capillary condensation and non-uniform slit-shaped pores while SBA-15 displays characteristic of a narrow range of mesopores with minimal network effects. Surface area, total pore volume and average pore diameter of KCC-1 are significantly greater than SBA-15 due to the presence of dendrimeric fibrous morphology. Under tested conditions, SO2 adsorption capacities of KCC-1 and SBA-15 are 614.01 mg/g and 274.64 mg/g, respectively. Superior performance by KCC-1 can be attributed to better accessibility of SO2 towards the active sites due to higher surface area provided by the dendrimer fibers.

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Performance of Waste Cooking Oil Esterification for Biodiesel Production Using Various Catalysts

2024-03-01 , Herman I.T. , Khairuddin Md Isa , Naimah Ibrahim , Saiful Azhar Saad , Abdullah T.A.T. , Aziz M.A.A. , Hairunnaja M.A.

In this study, waste cooking oil (WCO) with high free fatty acid (FFA) content was esterified to produce biodiesel, and the catalysts’ performance was investigated. Two deep eutectic solvents (DESs) were employed as the liquid catalysts (K2CO3-Gly and KOH-Gly), while the solid heterogeneous catalysts used were spent bleaching earth (SBE), KCC-1, and Na/KCC-1. DESs were prepared by mixing at reaction temperature and time of 80°C and 120 min, respectively. The American Standard Testing Method (ASTM) D974 determined the acid value. The catalysts were first screened for their catalytic activity in WCO esterification. The parameters investigated in this study were oil-to-methanol molar ratio, catalyst loading, reaction time, and temperature. The highest conversion (94.7%) was obtained using Na/KCC-1. The performance of solid and liquid catalysts was evaluated using KOH-Gly and SBE for the reduction of FFA in WCO under different conditions of oil-to-methanol molar ratio (1:6–1:10), catalysts loading (0.2–2.0 g), reaction time (30–60 min), and temperature (40–100°C). The highest reduction of FFA in the esterification process for KOH-Gly and SBE as catalysts was 97.74% and 84.2%, respectively. Transesterification of the esterified oil shows a promising result (97%), and the process can potentially be scaled up. The GC-MS result shows that the produced oil has the highest percentage of hexadecanoic acid and methyl ester.

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Evaluation of phenol formaldehyde resin synthesized from sugarcane bagasse bio-oil under optimized parameters

2022-04-01 , Ahmad S.F.K. , Umi Fazara Md Ali , Khairuddin Md Isa , Subash Chandra Bose Gopinath

Bio-oil from biomass is considered as a potential substitute to partially replace phenol in the preparation of phenol formaldehyde resin as replacement to the commercial phenol which high in cost. However, the percentages of bio-oil substitutions need to be determined to ensure that the performance is good as the commercial ones. The aim of this research is to identify the optimum conditions for synthesizing phenol formaldehyde resin (PF) and determines the percentages of bio-oil substitutions by manipulating the synthesizing variables such as formaldehyde to phenol (F/P) catalyst ratio (NaOH/P), catalyst ratio and duration using one-factor-at-time method. The effect of each manipulated variables on shear strength was compared to the Chinese National Standard for PF resin shear strength. Bio-based phenolic resins are synthesized using the optimum conditions by replacing 10, 20, 30 and 40% of phenol with bio-oil from the pyrolysis of sugarcane bagasse. The results obtained shown that the optimum conditions to synthesize phenol formaldehyde resin is at F/P molar ratio of 2.0, catalyst ratio of 0.6 and duration of 3 hour. The results of bio-based phenolic resins bonding performance shows that substitution percentage of bio-oil up to 20% at most gives good performance compared to the pure PF resin.

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Application of Mesoporous Silica as Catalyst Support in Sulfur Dioxide Removal: Metal and Amine Sorbent Modifications

2020-07-09 , Adli Hanif M. , Naimah Ibrahim , Khairuddin Md Isa , Abdul Jalil A.

Emission of hazardous SO2 into the atmosphere due to the burning of fossil fuels in various industries is detrimental not only to the environment but also to human beings. Various mitigation techniques have been implemented to overcome this problem, with flue gas desulfurization (FGD) method being the most commonly used. Dry FGD does not typically perform as good as wet method and requires new type of sorbent to be tested. Mesoporous silica (MS), a sorbent with porosity in the range of 2-50 nm is considered as attractive alternative due to its high specific surface area, ordered pore structures and wide array of morphologies. Due to relatively weak interaction between MS and SO2 adsorbate during dry FGD process, additives are introduced to overcome this problem. These MS are modified with basic additives which are deemed more favorable for SO2 adsorption. Metal and amine-based additives are commonly employed where the latter are reported to obtain higher adsorption capacity. Increasing additive loading is beneficial up to an optimal value depending on the types of additives.

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A single step transesterification process to produce biodiesel from the spent cooking oil

2021-05-24 , Indah Thuraya Herman , Khairuddin Md Isa , Naimah Ibrahim , Farizul Hafiz Kasim , Abd Aziz M.A.

A direct process of transesterification has been carried out to produce high yields of biodiesel. Conversion of waste cooking oil to methyl esters was performed using potassium hydroxide-glycerol (KOH-Gly) as a catalyst. KOH-Gly was produced by mixing KOH and glycerol at a mass ratio of 1:20 at a temperature of 80 oC for 120 minutes. The process of transesterification was performed at a reaction temperature of 60 oC, a molar ratio of oil to methanol of 1:6, 2% wt KOH-Gly catalytic loading for 30 minutes. This process resulted in a waste cooking oil conversion yield of about 97-98% to biodiesel using KOH-Gly as a catalyst. The two layers of the product were produced without the formation of soap, which facilitated the separation and purification process. Gas chromatography-mass spectrometry was used to analyse the chemical content of biodiesel.

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