Ras Izzati Ismail
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Ras Izzati Ismail
Official Name
Ras Izzati, Ismail
Alternative Name
Ismail, Ras Izzati binti
Ismail, R. I.
Ismail, Ras Izzati
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Scopus Author ID
57193309626
Researcher ID
AAI-8795-2021

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Estimating shelf-life of fresh Brazilian spinach: Paper and plastic packaging

2023-04-24 , Norawanis Abdul Razak , Amran M.A.F. , Sharon S. , Wei L.T. , Abd Razak Shaari , Lee Yit Leng , Ras Izzati Ismail , Sriyana Abdullah

The selection of packing materials is an important factor to prolong the shelf life of food products, especially for perishable foods or produces. This research was conducted to determine the effect of packing materials (papers and plastics) on fresh Brazilian spinach leaves quality such as moisture content, water activity and total color difference (Δη). The samples were stored at ambient temperature (25 °C) for 16 days. The moisture content and water activity of the samples were measure by moisture analyzer and water activity meter, respectively. The total color difference (Δη) was calculated based on L∗, a∗ and b∗ parameters. Generally, based on overall results, the packing materials significantly affected the quality of fresh Brazilian spinach leaves throughout 16 days of storage period. The results asserted that the paper materials are not suitable to use to pack fresh Brazilian spinach leaves for long period. It is also not recommended to use any paper material to pack fresh produce, especially perishable vegetables and fruits, in protecting their quality. The use of HDPE and PP plastics is recommended to prolong the shelf life of the fresh Brazilian spinach leaves. However, it has a limitation in controlling the changes of leaves color.

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The effect of silica toward polymer membrane for water separation process

2017-09-26 , Mohd Riduan Jamalludin , Rosli M.U. , Muhammad Ikman Ishak , Khor Chu Yee , Mohamad Suhaimi Shahrin , Ras Izzati Ismail , Lailina N.M. , Leng Y.L. , Hazrin Jahidi Jaafar

The aim of this present work was to investigate the effect of different percentage rice husk silica (RHS) particles composition towards polymer mixed matrix membrane microstructure and performance in water separation process. The polymer membranes were prepared by a phase inversion method using polysulfone (PSf), N-methyl-2-pyrrolidone (NMP) as solvent, distilled water as non-solvent and fixed RHS at 400°C as an additive. The microstructures of PSf/PEG/RHS sample were characterized by performing scanning electron microscope (SEM). The performance was measured by using pure water flux and humic acid for the rejection test. The analyzed result of SEM analysis revealed that the addition of RHS obviously improved the microstructure of the membrane especially at the top and sub layer at the range of 1 until 3 wt. %. This was proven by the pure water flux (PWF) value measured from 114.47 LMH to 154.04 LMH and rejection from value 83% to 96% at this specified range substantially higher than the mixed matrix membrane with synthetic silica. In fact, the presence of RHS particles not only improved the properties and performance of membrane but also possess biodegradable properties which can minimize the pollution and provide a membrane green technology system.

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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.

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Production of Solid Biofuels From Renewable Resources: A Review

2023-06-09 , Ras Izzati Ismail , Khor Chu Yee , Shaari A.R. , Alina Rahayu Mohamed , Abdul Halim M.H.B. , Rahman A.A.A. , Lee Yit Leng , Nur Lailina Makhtar , Norawanis Abdul Razak

Increasing concerns over greenhouse gas emissions, volatile fossil fuel prices, and political instability have led to biomass as a renewable energy source. Close cooperation from the government supported by independent bodies also helps produce this effective and sustainable energy source. As a result, the current growth of solid biofuels has increased tremendously. Agricultural, municipal, forest, commercial waste and dedicated energy crops are the main sources of biomass. Due to this biomass's nature, the methods to produce them into solid biofuels are also different. The energy potential of these biomass sources is quite dependent on the use of technology and public awareness. Therefore, this paper review feedstock biomass, processing processes, product types and properties of solid biofuels in terms of mechanical and combustion. The paper also reviews the solid biofuel production situation in Malaysia.

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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.

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Optimization of processing parameters for physical, mechanical and chemical properties of Khaya senegalensis fuel pellets

2024 , Ras Izzati Ismail

Flourishing even in less-than-ideal conditions, the rapid growth of the Khaya senegalensis (khaya) tree requires regular pruning, presenting a challenge in waste management. To address this, the study proposes repurposing the pruning waste to manufacture energy pellets, offering an eco-friendly solution to waste removal. Pellets offer improved energy density, bulk density, moisture content, and homogeneity, thereby reducing storage, handling, and transportation costs. Notably, there is a lack of scientific gap on using Khaya senegalensis wood for fuel pellet production. To produce high-quality solid fuel, it is essential to comprehend the properties of wood fuel. Due to this necessity, the current study examines the effects of pelletization temperature, pressure, particle size, feedstock moisture content and binder percentages on fuel pellet properties, particularly on their physical, mechanical and combustion characteristics. In this study, the methodology involved determining the fuel characteristics of Khaya senegalensis wood biomass, including bulk density and calorific value, followed by the fabrication of fuel pellets from varying feedstock parameters. The effects of these parameters on pellet properties were analyzed through a parametric study, and response surface methodology was employed to optimize the processing conditions for enhanced pellet quality. The study achieves its first objective by comprehensively assessing the fuel characteristics of Khaya senegalensis wood, with bulk density measured at 258 kg/m³, moisture content (26.06 %), ash content (5.38 %), volatile matter (83.07 %), fixed carbon (15.46 %), and calorific values (16.11 MJ/kg). The second objective involves a parametric study, investigating the effects of pelletizing parameters on mechanical strength and combustion characteristics. The study successfully establishes relationships and optimized conditions for various parameters, presenting statistically significant findings in response analysis. The third objective employs response surface methodology to optimize pelletizing variables for ideal mechanical and combustion characteristics, resulting in well-validated models and predicted optimized values. Design Expert 13 revealed that khaya pellets performed optimally with factor settings of pelletization temperature at 110 °C, pressure at 5 tonnes, and a binder percentage of 9 %. The optimized values for various responses include axial compressive strength at 55.66 MPa, diametral compressive strength at 9.604 MPa, moisture content at 6.93 %, volatile matter at 87.83 %, ash content at 6.54 %, fixed carbon at 5.31 %, calorific value at 19.08 MJ/kg, durability at 99.93 %, and unit density at 1309.37 kg/m³. In conclusion, all the objectives have been successfully achieved, and the research provides valuable insights into repurposing khaya wood waste for sustainable energy pellet production. Understanding wood biomass, solid fuel qualities, and pelletization parameters for this crop could streamline the production of premium-quality pellets from khaya wood, addressing global energy demands efficiently.

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

2020 , Ras Izzati Ismail , Lee Yit Leng , Nur Lailina Makhtar , A A A Rahman , J A A Dali , A R Shaari , Khor Chu Yee , A R 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.

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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.

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Quantification of the torrefaction influenceon lignin composition of Khaya senegalensis biomass

2023 , Adli Azimi Abdul Rahman , Ras Izzati Ismail , AbdulRazak Shaari , Nik Noriman Zulkepli

In Malaysia, Khaya senegalensis has been introduced as landscape and shade tree. However, Khaya senegalensis has few suitable characteristics to be developed as future energy crops. Fast growing and can be planted in marginal soil are among the important criteria of energy crop that belong to this species. This research was conductedto determine the influence of torrefaction on the lignin composition of the biomass, as it can influence the performance as feedstock for bioenergy production. The biomass sample was torrefied at different temperature (225, 250, 275 and 300°C) and different duration(30, 60, 90 minutes). The result shows that the torrefaction severity has the significant impact on the weight loss and lignin composition of the biomass sample. The total lignin of the torrefied sample increases when the torrefaction severity increases. It was found thatthe changes in the lignin composition have strong correlation with the calorific value of the biomass.

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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.

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