Alina Rahayu Mohamed
Thumbnail Image
Preferred name
Alina Rahayu Mohamed
Official Name
Alina Rahayu, Mohamed
Alternative Name
Rahayu, M. Alina
Mohamed, Alina Rahayu
Rahayu Mohamed, Alina
Main Affiliation
Scopus Author ID
55349453800
Researcher ID
DHI-6721-2022

Research Output

Filters

20 2
5 1
20
Reset filters

Settings
Now showing 1 - 10 of 20
Thumbnail Image
Publication

Kinetics Analysis on Catalytic Pyrolysis of Empty Fruit Bunch (EFB) with Copper Oxide Doped Aluminium Oxide (CuO/Al2O3) Catalyst

2020-12-18 , Alina Rahayu Mohamed , Zin A.M. , Siti Nor Azreen Ahmad Termizi , Khairunissa Syairah Ahmad Sohaimi , Izhar N.I.I.N.

This study focuses on dynamic non-catalytic and catalytic pyrolysis of empty fruit bunch (EFB) with copper oxide doped aluminium oxide (CuO/Al2O3) at linear ramp rates of 10, 15, 20, 25, 30 and 40 Cmin-1 at pyrolysis temperature of 28-1000 C in a thermogravimetric analyzer (TGA). The thermogravimetric profiles for the thermochemical breakdown of EFB under non-catalytic and catalytic pyrolysis with CuO/Al2O3 comprise of three different levels. The kinetics analysis for the reactions were evaluated using the Kissinger and Ozawa methods. The values of activation energy (Ea) for non-catalytic EFB pyrolysis were 167.95 and 177.68 kJmol-1 based on Kissinger and Ozawa methods respectively. For catalytic pyrolysis with approximately 9.09 wt% CuO/Al2O3 catalyst, the values of Ea reduced to 127.72 and 137.42 kJmol-1 by Kissinger and Ozawa methods respectively. These values indicate that the presence of 9.09 wt% CuO/Al2O3 catalyst has successfully reduced Ea value for the EFB pyrolysis reaction.

View
Thumbnail Image
Publication

The Effect of Different Waste Material Binders in Relation to Khaya Senegalensis Solid Fuel Pellet Quality

2023-11-01 , Ras Izzati Ismail , Khor Chu Yee , Alina Rahayu Mohamed , Mustafa N.M.K.N. , Lee Yit Leng , Nur Lailina Makhtar , Norawanis Abdul Razak

Fuel pellets are an attractive renewable energy source derived from biomass sources thanks to their uniformity and ease of handling. However, raw biomass and waste material binders have several drawbacks, which include poor physical properties, particularly low density and compositional heterogeneity, which restrict their wider use as a general source of energy. Besides, due to the low energy density, low bulk density, and uneven shape and size of raw biomass, it is very difficult to store and transport biomass in its original form, which decreases transport efficiency. This study investigated the effect of waste material binders (rice husk, corn cob, and sugarcane bagasse) on the mechanical and thermal properties of Khaya Senagalensis pellets. The mechanical and thermal properties were determined according to ASTM standards. Waste material binders have affected pellet quality such as density, bulk density, moisture content, durability, compressive strength, shatter index, water resistance, ash content, volatile matter, fixed carbon, and calorific value. From the analysis, sugarcane bagasse as a binder shows the highest quality pellet in terms of mechanical properties. Sugarcane bagasse produces the highest density (0.967g/cm3), bulk density (0.4094), durability (99.71%), shatter index (98.85%), water resistance (98.35%), and thermal properties, which are the highest volatile matter (94.71%) and the lowest ash content (1.71%). In a nutshell, sugarcane bagasse is a good binder that gives a positive impact to the K.senegalensis pellets in terms of storage and transportation compared to corn cob and rice husk binder.

View
Thumbnail Image
Publication

Durability properties of demineralized and torrefied Empty Fruit Bunch (EFB) pellets

2020 , Alina Rahayu Mohamed , Ras Izzati Ismail , Rashid, Mohammad Abdur , Khairunissa Syairah Ahmad Sohaimi , N N Kasim , R Badlishah Ahmad

The pelletization of raw and demineralized and torrefied empty fruit bunch (TDEFB) were conducted upon mixing with bio-oil that was obtained from EFB pyrolysis. The ratio of bio-oil addition to raw and TDEFB was varied from 0-20 wt%. Then it was pressed using the single pellet press machine. The effects of the ratio of bio-oil addition to raw and TDEFB and the thickness of pellets were evaluated towards its durability. It was identified that the ratio of bio-oil addition to raw and TDEFB pellet of 5 wt% had produced the optimum durability which was 69.27 and 74.46 % respectively. In terms of the thickness of the raw and torrefied pellets, it was determined that at thickness of 3 cm, the durability was the highest which were 70.12 and 71.12 % for both raw and TDEFB pellets respectively. The raw and TDEFB pellets were analysed using Fourier Transform Infra-Red (FTIR) spectroscopy in order to evaluate the presence of functional groups within the materials. The presence of O-H hydroxyl group, C=O from carbonyl or ester and C-H alkane groups are detected in both raw and torrefied pellets.

View
Thumbnail Image
Publication

The effect of torrefaction reaction temperature on the Elaeis Guineensis Empty Fruit Bunch (EFB) pellet durability and calorific value

2020-12-18 , Ras Izzati Ismail , Leng L.Y. , Nur Lailina Makhtar , Rahman A.A.A. , Dali J.A.A. , Abd Razak Shaari , Yee K.C. , Alina Rahayu Mohamed , Mohd Riduan Jamalludin , Norawanis Abdul Razak , Wan Nur A'tiqah Wan Draman

Empty Fruit Bunch (EFB) are not being fully utilized for energy production due to its high moisture content, low density, having bulky characteristics and low calorific value. In order to improve characteristic of Elaeis Guineensis empty fruit bunch as fuel, pre-treatment process is necessary to overcome these shortcomings. Therefore, the aim of this research is to examine the effect of torrefaction reaction temperature on the Elaeis Guineensis pellet energy characteristics. The observed pellet qualities include the pellet durability and calorific value of the pellet. The torrefaction of empty fruit bunch was conducted in a fixed-bed reactor at 200 C, 220 C, 240 C and 260 C. The torrefied sample was pelletized, analysed and tested to examine the characteristics of empty fruit bunch biomass as fuel. The pelletization process was carried out by using the cold single press pelletizer and using cassava starch as binder. At higher torrefaction temperature, the decomposition of cellulose and lignin become more prominent. At the torrefaction temperature 260 C, the gross calorific value is the highest due to the removal of moisture, release of volatile matter and the decomposition of biomass components such as hemicellulose, cellulose and lignin which resulted in energy densification. By comparing the torrefied empty fruit bunch at 260 C with the untorrefied empty fruit bunch, it was found that the torrefaction increased the energy densification and pellet qualities of empty fruit bunch that can be utilized as biomass energy sources in renewable energy.

View
Thumbnail Image
Publication

Synthesis of ultrasonicated amine-functionalized MgO-deposited empty fruit bunch (EFB)-derived biochar for CO2 adsorption

2024-01-01 , Shafawi A.N. , Mohd Amer N. , Aghamiri A.R. , Lahijani P. , Mohammadi M. , Alina Rahayu Mohamed

In this study, biochar derived from empty fruit bunch (EFB) was modified by sonication, amine functionalization, and MgO deposition to increase CO2 uptake capacity towards addressing the global warming problem. The optimal conditions for amine functionalization were a biochar to melamine mass ratio of 5:2, an activation temperature of 700 Â°C, and a heating rate of 15 Â°C/min. The sequential sonication, amine functionalization, and MgO deposition resulted in the ultrasonicated amine-functionalized MgO-deposited biochar (UAMB) with the highest CO2 uptake capacity of 84.95 mg/g, which is a 142% increase compared to the pristine biochar (35.10 mg/g). The results of XRD, SEM–EDX, FTIR, Raman, BET, Boehm titration, and XPS analysis showed that the sequential treatments improved the porosity, surface area, and surface chemistry of the modified biochar due to the presence of MgO, pyridine, pyrrole, and nitrile, resulting in a superior increase in CO2 uptake capacity. Advantageously, this modified biochar exhibited the highest affinity for CO2 compared to air, methane, and nitrogen and was stable up to 12 cycles of CO2 adsorption–desorption. Kinetic studies showed that the Avrami kinetic model best described CO2 adsorption on the biochar, with physisorption being the main adsorption mechanism and chemisorption making only a minor contribution to CO2 adsorption. CO2 capture tests in a fixed-bed adsorption system showed that the best adsorption conditions were at a gas flow rate of 30 mL/min, an initial CO2 concentration of 15%, and an adsorption temperature of 30 Â°C. The excellent performance of this modified biochar is promising for efficient CO2 capture to reduce CO2 emissions.

View
Thumbnail Image
Publication

Mechanical and physical properties of khaya senegalensis solid fuel pellet with different binder percentages

2021-10-25 , Ras Izzati Ismail , Shaari A.R. , Khor Chu Yee , Alina Rahayu Mohamed , Rahim M.S.b.A. , Lee Yit Leng , Wan Nur A'tiqah Wan Draman , Nur Lailina Makhtar , Norawanis Abdul Razak , Mohd Riduan Jamalludin

The characteristics of the solid fuel pellets, such as its strength, durability and density can be used to assess its quality. During the transport and storage, pellets with low strength and durability produces dusts and ultimately resulting in equipment blockage, high pollution emissions, and an increased risk of fire and explosion. Therefore, pellet manufacturing process should be given priority to improve pellet quality. The use of binder in the production of pellets will aid in improving pellet quality. Therefore, this study investigates the influence of different binder percentages on the mechanical properties of K. senegelensis fuel pellets. Durability, unit density, bulk density and diametral compressive strength testing were carried out in compliance with international standards. It was discovered that pellets containing 4% cassava starch binder produces better results, particularly in terms of durability and compressive ldiametral strength.

View
No Thumbnail Available
Publication

Building Stronger Biomass : How Particle Size Affects the Physical and Mechanical Properties of Khaya senegalensis Fuel Pellets

2025-06-10 , Ras Izzati Ismail , Khor Chu Yee , Alina Rahayu Mohamed

Biomass has gained significant attention as a renewable energy source due to its potential to reduce dependency on fossil fuels and lower carbon emissions. Among various biomass-derived fuels, pelletized biomass offers enhanced energy density, improved combustion efficiency, and ease of handling and storage. Khaya senegalensis, a fast-growing tree that thrives in suboptimal conditions, requires regular pruning, leading to significant biomass waste. This study examines the influence of feedstock particle size on the mechanical properties of Khaya senegalensis fuel pellets. Biomass trimmings from Khaya tree branches were collected, processed into wood chips, and ground into five particle sizes (0.1, 0.3, 0.5, 1, and 2 mm) before pelletization. The pellets were produced under constant moisture content, pressure, temperature, and binder percentage. A one-factor-at-a-time (OFAT) approach was employed, with each process repeated three times to ensure consistency. The mechanical properties analyzed include unit density, durability, axial compressive strength, and diametral compressive strength. Experimental data are analyzed using analysis of variance (ANOVA) to examine correlations between feedstock particle sizes and mechanical properties. This study establishes that particle size plays a crucial role in determining the physical and mechanical properties of Khaya senegalensis wood pellets. The results indicate that finer particles (0.15 mm) contribute to higher unit density and durability, whereas coarser particles (1.00 mm) enhance compressive strength.

View
Thumbnail Image
Publication

Inhibition of Aspergillus flavus by Momordica charantia Ethanolic Leaves Extract for Mushroom Protection

2023-06-09 , Noor Hasyierah Mohd Salleh , Zulkarnay Zakaria , Aziz N.H. , Ahmad Anas Nagoor Gunny , Alina Rahayu Mohamed , Munusamy T.

Pleurotus ostreatus, better known as oyster mushroom is one of the world’s widely cultivated mushroom. Infection from pathogenic fungi is one of the major reasons causing losses of mushroom during cultivation. The objective of this study is to investigate the antifungal property of Momordica charantia leaves extract against Aspergillus flavus for mushroom protection. The inhibitory effect of M. charantia leaves extract against A. flavus isolated from infected P. ostreatus mushroom bag was investigated using pour plate technique. Inhibition of A. flavus mycelial growth was the highest at extract concentration of 9.64 v/v %, temperature 26℃ and incubation time of 96 hours with inhibitory value of 70.58 ± 0.00 %, 78.4 ± 0.00 % and 63.33 ± 2.89 % respectively. Structural morphology of the mycelia grown on the treated plate also showed morphological alteration compared to the control plate. Hence, Momordica charantia leaves extract may serves as a promising fungicides alternative to chemical use for controlling invasion of A. flavus on oyster mushroom.

View
Thumbnail Image
Publication

Thermal pyrolysis of empty fruit bunch (EFB) in a vertical fixed-bed reactor

2020 , Alina Rahayu Mohamed , A N Awang , Noor Hasyierah Mohd Salleh , R Badlishah Ahmad

In the production of crude palm oil, huge quantities of solid biomass waste is generated such as empty fruit bunch (EFB), palm fronds and palm–pressed fibre (PPF). This inevitably resulted in the environmental pollution due to its natural conversion to methane. In this study, thermal pyrolysis of EFB was conducted using a fixed bed reactor. The factors such as nitrogen gas flowrate and holding time that affect the distribution of pyrolysis product yields were being investigated by evaluating the percentage product yields. It was determined that at nitrogen gas flowrate of 300 cm3/min and 30 mins holding time, the maximum bio-oil yield of 46.20 % was attained with gas and char yield of 21.79 % and 32.01 % respectively. The existence of functional groups in bio-oil was analyzed by Fourier Transfrom Infra-Red (FTIR) spectroscopy. It was identified that the bio-oil has several functional groups such as hydroxyl (OH), ketone/aldehyde (C=O) and ester (O-C=O) groups. The dynamic viscoscity of bio-oil was analyzed by Brookfield viscometer. It showed that the viscosity of bio-oil decreased with increasing temperature from 25-50 °C.

View
Thumbnail Image
Publication

Thermal and catalytic pyrolysis of palm-pressed fibre with copper oxide doped zirconia CuO/ZrOâ‚‚ catalyst in a fixed-bed reactor

2020 , Alina Rahayu Mohamed , Aznie Nadiera Awang , D M Hassan , N Nordin , R Badlishah Ahmad

The utilization of agriculture solid waste such as palm pressed fibre (PPF) in pyrolysis reaction is an alternative way in converting the solid waste into bio-oil. In this research, thermal and catalytic pyrolysis of PPF was conducted using a tubular fixed bed reactor. A series of CuO/ZrO₂ catalysts were prepared using the aqueous sol-gel technique. The catalysts were calcined at 400, 600 and 800 °C for 17 hours. The thermal and catalytic pyrolysis of PPF were carried out at 500 °C pyrolysis temperature for 5 minutes holding time using PPF particle size of 250-500 µm. The pyrolysis results showed that 44.35% bio-oil was obtained under thermal condition and their yields reduced to 41.07%, 35.45% and 38.18% respectively when CuO/ZrO₂ catalysts calcined at 400, 600 and 800 °C were incorporated in PPF pyrolysis. The bio-oil was analyzed by using fourier transform infrared (FTIR) spectroscopy for the determination of functional groups. It was found that bio-oil from thermal and catalytic conditions possessed oxygenated functional groups such as aldehyde, ketone and carboxylic acid. In addition, the bio oil from catalytic conditions CuO/ZrO₂ catalysts calcined at 400 and 600 °C showed the presence of saturated hydrocarbon.

View