Razi Ahmad
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Preferred name
Razi Ahmad
Official Name
Razi, Ahmad
Alternative Name
Ahmad, Razi
Ahmad, R. B.
Ahmad, R.
Ahmad, R. Badlishah
Main Affiliation
Scopus Author ID
54419444500
Researcher ID
B-9254-2012

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Publication

Influence of Torrefaction on Sewage Sludge

2023-01-01 , Razi Ahmad , Abdul Ghapar Ahmad , Mohammed S.A. , Wan Ahmad W.A.M. , Vikneswaran Vijean , Ragunathan Al Santiagoo , Ibrahim N.R. , Udin N.

Sewage sludge (SS) from sewage treatment plants has been seen as a waste for decades and little attention to investigate the potential and its beneficial product. SS contain a large amount of recoverable energy; however, it has high moisture, ash, heavy metals, and organic contents. Thus, the goal of this research is to use torrefaction to produce upgraded or torrefied SS. The proximate and ultimate analysis was used to determine the physical and chemical characteristic of raw SS. Torrefaction was performed through inert atmosphere in fixed bed reactor. According to the findings, at torrefaction temperature of 300 °C, torrefaction had improved the quality of raw SS, increasing its fixed carbon content by 47.8%, and its moisture content by 61.3%. The optimum temperature for torrefaction was at 300 ℃ with holding time of 60 minutes. This study improved the quality of sewage sludge to be utilised in subsequent thermochemical conversion.

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Influence of pretreated coconut shell on gasification product yield

2023-10-16 , Muda S.Z. , Razi Ahmad , Syakirah Afiza Mohammed , Wan Amiza Amneera Wan Ahmad , Vikneswaran Vijean , Ibrahim N.R. , Ani A.Y. , Ragunathan Al Santiagoo

Gasification of untreated and pretreated coconut shell (CS) was carried out in a fixed-bed reactor to assess the effect of temperature (600, 650, 700, 750, and 800 C) and holding time (30 and 40 min) on gases composition. The untreated CS was first torrefied in a fixed-bed reactor at different temperatures (200 â 300 C) and holding times (30 min, 60 min and 90 min). Pretreated CS at the optimal torrefaction temperature (275 C and 60 min) was used for gasification. Under optimal conditions of 750 C and 30 min holding time, gasification contributed the most gas production. At this optimum condition, the gas composition of pretreated CS was 35.03 % of CH4, 24.43 % of CO2, and 40.54 % of H2 + CO. Untreated CS contains 37.63 % of CH4, 24.03 % of CO2, and 38.34 % of H2 + CO gases. The production of CH4 gas was higher when untreated CS was used for gasification rather than pretreated CS. Moreover, when untreated CS was used for gasification, the amount of CO2, H2, and CO produced was minimal. Therefore, for high H2 production, pretreatment prior to gasification is appropriate.

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Bio-Char And Bio-Oil Production From Pyrolysis of Palm Kernel Shell And Polyethylene

2023-01-01 , Ibrahim N.R. , Razi Ahmad , Wan Amiza Amneera Wan Ahmad , Vikneswaran Vijean , Ragunathan Al Santiagoo , Syakirah Afiza Mohammed , Khalid A.F. , Ani A.Y.

In recent years, palm kernel shell (PKS) has become a viable feedstock for making biofuels and value-added commodities using a variety of thermal conversion routes. Therefore, significant conservation is required for PKS as a resource for fuel production in biofuel facilities. Thus, this research was intended to elucidate the effects on PKS as a solid fuel through torrefaction and the production of bio-char and bio-oil by single and co-pyrolysis of PKS and polyethylene (PE). The PKS was treated through torrefaction at different temperatures and holding times. The optimum parameters for torrefaction were a temperature of 250 oC and a holding time of 60 min. Then the PKS and PE were pyrolyzed in a fixed-bed reactor at different temperatures and ratios. The product yield was analysed for single and co-pyrolysis of PKS and PE for pyrolysis. The properties of the product composition for single and co-pyrolysis of the PKS and PE were determined by proximate analysis, Fourier transform infrared (FTIR) analysis, and gas chromatography-mass spectrometry (GC-MS). The optimum parameter obtained for biochar and bio-oil production from co-pyrolysis of PKS and PE was at temperature of 500 oC at a ratio of 1:2 (PKS: PE). The ester and phenol compounds were increased around 19.02 to 23.18% and 32.51 to 34.80 %, respectively, while amide and amine decreased around 4.94 to 18.87% and 0.63 to 32.39 %, respectively, compared to the single pyrolysis of PKS. Therefore, the PKS and PE co-pyrolysis significantly increased the amount of phenol and ester compounds while slightly reducing the amount of amide and amine compounds in the bio-oil product. As a conclusion, biomass conservation enables the manufacturing of value-added chemicals.

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Potential of pretreated palm kernel shell on pyrolysis

2023-01-01 , Razi Ahmad , Ragunathan Al Santiagoo , Abdul Ghapar Ahmad , Syakirah Afiza Mohammed , Wan Ahmad W.A.M. , Vikneswaran Vijean , Ibrahim N.R.

The impact of pretreatment on palm kernel shell (PKS) with torrefaction for the possibility of pyrolysis is discussed in this study. PKS samples were torrefied at different holding times of 30 and 60 minutes at temperatures of 200, 225, 250, 275, and 300 °C. In a fixed-bed reactor with a constant nitrogen flow rate of 500 ml/min, torrefaction pretreatment was carried out. The elemental composition, mass, and energy yield, as well as proximate analysis, were all performed on the pretreated PKS. The optimised pretreated PKS was pyrolyzed next at a temperature of 400 to 550 °C in a fixed-bed reactor. The outcomes demonstrated that the pretreated PKS had a significant mass and energy yield at a temperature of 250 °C and a holding time of 30 min. PKS's calorific value and carbon content both rose after pretreatment. However, the oxygen and moisture content decreased for pretreated PKS. The maximum bio-oil production of 58% was achieved during the pyrolysis of pretreated PKS at a temperature of 500 °C. At higher temperature of 550 ℃, the bio-oil decreased due to secondary cracking reaction. Consequently, the pretreated PKS has greater potential as effective feedstock for successive proses particularly pyrolysis for bio-oil production.

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Compatibilizers Effect on Recycled Acrylonitrile Butadiene Rubber with Polypropylene and Sugarcane Bagasse Composite for Mechanical Properties

2023-10-16 , Zainal M. , Ragunathan Al Santiagoo , Razi Ahmad , Mohammed S.A. , Abdul Ghapar Ahmad , Vikneswaran Vijean , Wan Amiza Amneera Wan Ahmad , Allan Melvin Andrew

Compatibilizers effect on recycled acrylonitrile butadiene rubber (NBRr) with polypropylene (PP) and sugarcane bagasse (SCB) composite for mechanical properties is evaluated. Trans-Polyoctylene Rubber (TOR) and Bisphenol a Diglycidyl Ether (DGEBA) are used as compatibilizers in this study. Three (3) different composites (80/20/15, 60/40/15, and 40/60/15), with fixed filler (15 phr) and compatibilizers (10 phr) content, were carried out. These composites were arranged via melt mixing technique utilizing a heated two-roll mill at a temperature of 180 C for 9 minutes employing a 15-rpm rotor speed. Tensile and morphological properties were evaluated. The result shown average tensile strength dropped by 48.50% as the recycle NBR content rises 20 phr. Nevertheless, subsequent compatibilization reveals that the compositesâ tensile properties were all greater than control composites. The morphology discovered validates the tensile properties, indicating a stronger interaction between the PP/SCB and recycle NBR composites with the addition of compatibilizer DGEBA.

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Influence of carbonisation temperature on the surface pore characteristics of acid-treated oil palm empty fruit bunch activated carbon

2020-07-01 , Ahmad N. , Naimah Ibrahim , Fu P.Y. , Razi Ahmad

Carbonisation process affects the surface physical and chemical properties of an activated carbon. Therefore, this work aims to investigate the influence of carbonisation temperature from 400 to 550° C during activation with 85% phosphoric acid (H3PO4) on the surface pore characteristics of activated carbon produced from oil palm empty fruit bunch (EFB) for nitric oxide (NO) removal from gas streams. Pore and morphological characterisation showed that EFB carbonised at 400° C (EFBC-400) is microporous and has a uniform pore structure with 98% micropore volume. Increasing carbonisation temperature resulted in pore enlargement from 2.8 to 4.7 nm and increment in pore heterogeneity and BET surface area from 215 to 759 m2/g. However, the NO breakthrough experiment indicated that EFBC-400 is more favourable for low-temperature NO removal, due to the importance of microporosity in adsorption of NO. Further study will look at the kinetics of NO removal and the adsorbent regeneration.

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