Heah Cheng Yong
Thumbnail Image
Preferred name
Heah Cheng Yong
Official Name
Heah, Cheng Yong
Alternative Name
Yong, Heah Cheng
Yong, H. C.
Heah, Cheng Yong
Heah, C. Y.
Cheng-Yong, Heah
Cheng Yong, Heah
Main Affiliation
Scopus Author ID
54402789500
Researcher ID
S-7139-2019

Research Output

Filters
Reset filters

Settings
Now showing 1 - 10 of 88
Thumbnail Image
Publication

Turning waste into strength enhancing geopolymer composites with Oil Palm Frond Fibers (OPF)

2024-10 , Ng Hui-Teng , Liew Yun Ming , Heah Cheng Yong , Tan Soo Jin , Muhammad Aqil Asyraf Bin Mohd Roslan , Siti Khadijah Binti Zulkepli , Tan You How , Ng Yong-Sing

Geopolymers are alternatives to ordinary Portland cement as construction materials. The increasing demand for sustainable construction materials has driven the utilization of industrial by-products and agricultural waste. The disposal of oil palm frond (OPF) biomass as waste in landfills poses significant environmental challenges, necessitating effective recycling strategies. This study examines the incorporation and feasibility of OPF as a reinforcing fiber in fly ash geopolymer composites, examining its impact on physical and mechanical properties. Various parameters were tested, including fiber content (10–20 wt.%), shapes (shredded and tubular), and lengths (1–3 cm). The geopolymer composites with 10 wt.% shredded oil palm frond and 1-cm tubular oil palm frond fibers enhance the compressive strength by 17% compared to the control sample without oil palm frond. The shredded oil palm frond was particularly effective, enhancing strength performance and achieving better dispersion within the geopolymer matrix. Conversely, increasing the fiber content and length generally resulted in diminished composite strength, attributed to the creation of a more porous structure and weaker fiber-matrix interactions. However, lower fiber additions were shown to decrease porosity and water absorption, highlighting the potential of optimized oil palm frond fiber content and form in improving the environmental and mechanical performance of geopolymer composites. These results support the viability of oil palm frond as a sustainable additive in geopolymers, contributing to waste reduction and material innovation in construction.

View
Thumbnail Image
Publication

Improvements of flexural properties and thermal performance in thin geopolymer based on fly ash and ladle furnace slag using borax decahydrates

2022 , Ng Yong-Sing , Liew Yun Ming , Heah Cheng Yong , Mohd. Mustafa Al Bakri Abdullah , Phakkhananan Pakawanit , Petrica Vizureanu , Mohd Suhaimi Khalid , Ng Hui-Teng , Hang Yong-Jie , Marcin Nabiałek , Paweł Pietrusiewicz , Sebastian Garus , Wojciech Sochacki , Agata Śliwa

This paper elucidates the influence of borax decahydrate addition on the flexural and thermal properties of 10 mm thin fly ash/ladle furnace slag (FAS) geopolymers. The borax decahydrate (2, 4, 6, and 8 wt.%) was incorporated to produce FAB geopolymers. Heat treatment was applied with temperature ranges of 300 °C, 600 °C, 900 °C, 1000 °C and 1100 °C. Unexposed FAB geopolymers experienced a drop in strength due to a looser matrix with higher porosity. However, borax decahydrate inclusion significantly enhanced the flexural performance of thin geopolymers after heating. FAB2 and FAB8 geopolymers reported higher flexural strength of 26.5 MPa and 47.8 MPa, respectively, at 1000 °C as compared to FAS geopolymers (24.1 MPa at 1100 °C). The molten B2O3 provided an adhesive medium to assemble the aluminosilicates, improving the interparticle connectivity which led to a drastic strength increment. Moreover, the borax addition reduced the glass transition temperature, forming more refractory crystalline phases at lower temperatures. This induced a significant strength increment in FAB geopolymers with a factor of 3.6 for FAB8 at 900 °C, and 4.0 factor for FAB2 at 1000 °C, respectively. Comparatively, FAS geopolymers only achieved 3.1 factor in strength increment at 1100 °C. This proved that borax decahydrate could be utilized in the high strength development of thin geopolymers.

View
Thumbnail Image
Publication

Mechanical Properties and Thermal Conductivity of Lightweight Foamed Geopolymer Concretes

2019-08-14 , Fatimah Azzahran Abdullah S. , Yun-Ming L. , Mohd. Mustafa Al Bakri Abdullah , Heah Cheng Yong , Zulkifly K.

Foamed geopolymer concretes have a better performance in the thermal insulation properties compared to normal geopolymer concretes. In this research, lightweight aggregate geopolymer concretes was incorporated with different percentage of foaming agents (hydrogen peroxide). Compressive strength and thermal conductivity were measured. From results obtained, increased H2O2 contents will decrease the strength of lightweight foamed geopolymer concretes. Lightweight aggregate foamed geopolymer concretes (LWAFGC) with foaming agent content of 0.2wt.% obtained the highest strength of 19.601 MPa. Furthermore, Increased of H2O2 contents also will decrease the thermal conductivity of lightweight foamed geopolymer concretes. Lightweight foamed geopolymer concretes with 2wt.% H2O2 gave the good thermal insulating behavior when the thermal conductivity value recorded the lowest value compare to other wt.% of H2O2 content. The thermal conductivity value of lightweight foamed geopolymer concretes with 2wt.% of H2O2 was 0.072 W/m. K while, the thermal conductivity of other mixtures ranged between 0.077 W/m. K to 0.087 W/m. K., respectively.

View
Thumbnail Image
Publication

Thermo-mechanical behaviour of fly ash-ladle furnace slag blended geopolymer with incorporation of decahydrate borax

2022-05-09 , Ng Hui Teng , Heah Cheng Yong , Liew Yun Ming , Mohd. Mustafa Al Bakri Abdullah , Rojviriya C. , Ken P.W. , Ong Shee Ween , Hang Yong Jie , Ooi Wan En

This paper elucidates the effect of adding decahydrate borax (1 and 2 wt%) on thermo-mechanical properties of fly ash-ladle furnace slag (FS) geopolymer at 29 °C – 1000 °C. Adding borax improved the compressive strength of unheated (40.5 MPa) and heat-treated (36.9 – 43.1 MPa) FS geopolymers by 8.4% and 21.2%, respectively. The higher crystallinity, incompact microstructure, and the presence of B-bonds and B-crystals contributed to the high-temperature resistance of FS-B geopolymer. The reduced sintering temperature by 75 °C due to addition of borax compared to FS geopolymer improved the thermal stability and structural integrity during high-temperature applications.

View
Thumbnail Image
Publication

Microstructural Analysis of Fly Ash-based Geopolymers with various Alkali Concentration

2019-08-14 , Hui-Teng N. , Heah Cheng Yong , Yun-Ming L. , Mohd. Mustafa Al Bakri Abdullah , Yong-Sing N.

In the present work, a comparative study on the effect of different concentration of sodium hydroxide (NaOH) on fly ash-based geopolymer was investigated. The geopolymer synthesis by mixing fly ash with alkali activator (a mixture of NaOH and sodium silicate) at solid/liquid ratio of 2.5. The NaOH were used 6M, 8M, 10M, 12M and 14M with constant sodium silicate/NaOH ratio of 2.5. The geopolymers were cured at room temperature (29°C) for 24 hours and 60°C in oven for another 24 hours. The testing and analysis of the fly ash-based geopolymers were performed after 28 days. The adequate Na+ ions and densified microstructure were observed at optimum 8M-NaOH-activated fly ash-based geopolymers.

View
Thumbnail Image
Publication

Discovering the roles of electrode distance and configuration in dye degradation and electricity generation in photocatalytic fuel cell integrated electro-Fenton process

2022-01-01 , Thor S.H. , Ho Li Ngee , Ong Soon An , Che Zulzikrami Azner Abidin , Heah Cheng Yong , Nordin N. , Ong Y.P. , Yap K.L.

Photocatalytic fuel cell (PFC) integrated electro-Fenton (EF) system (PFC-EF system) was considered as an eco-friendly approach for dye degradation and electricity generation simultaneously. The modification on configuration of PFC-EF system was aimed to improve the dye degradation and power output. Effect of electrode distance on the efficiency of PFC-EF system was investigated as it was a crucial factor in the mass transfer of ions in PFC-EF system. Closer electrode distance reduced the resistance flow of ions and enhanced the mass transfer of ions between the electrodes in both PFC and EF, eventually yielded higher concentration of reactive species for removal of dye. Four different electrode configurations by varying the number of cathodes in PFC and EF were investigated to discover the most efficient operating configuration for this PFC-EF system. The dye decolourization rate was evaluated and compared by using pseudo-first order and second order in both PFC and EF system, respectively. Results revealed that single cathode PFC-EF system was the most effective configuration in dye degradation while double cathodes PFC-EF system was the optimal configuration to be used for power output.

View
No Thumbnail Available
Publication

Asas Geopolimer Teori & Amali

2013 , Mohd. Mustafa Al Bakri Abdullah , Rafiza Abd Razak , Zarina Yahya , Kamarudin Hussin , Liew Yun Ming , Heah Cheng Yong , Mohd Izzat, Ahmad

Buku Asas Geopolimer: Teori dan Amali ialah sebuah buku yang membincangkan beberapa perkara asas yang penting mengenai geopolimer. Ia meliputi aspek-aspek seperti; Sejarah geopolimer Pengenalan kepada geopolimer Perbandingan konkrit geopolimer dengan konkrit biasa Bahan mentah dalam geopolimer Tindak balas kimia Kaedah pemprosesan Kualiti konkrit geopolimer Penyelidikan geopolimer masa kini Penulisan buku ini menumpukan kepada teori asas, proses dan pencirian geopolimer yang memberi pengetahuan kepada pembaca mengenai teori dan praktikal berasaskan hasil penyelidikan yang dibuat penyelidik. Tiga perkara utama yang dibincangkan di dalam buku ini ialah bahan mentah (larutan pengaktif alkali), tindak balas kimia yang memainkan peranan dalam proses pengeopolimeran dan pemprosesan geopolimer. Buku Asas Geopolimer: Teori dan Amali ini juga adalah buku pertama yang dihasilkan dalam Bahasa Melayu.

View
Thumbnail Image
Publication

Formulation, mechanical properties and phase analysis of fly ash geopolymer with ladle furnace slag replacement

2021 , Ng Hui-Teng , Heah Cheng Yong , Kong Ern Hun , Mohd. Mustafa Al Bakri Abdullah , Liew Yun Ming , Hasniyati Md Razi , Ng Yong-Sing

This paper presents the formulation of fly ash (FA) geopolymer and the incorporation of ladle furnace slag (LFS) as a replacement to FA in geopolymer formation. The formulation of the LFS replacement was set at 10–40 wt.%. The geopolymer was formed by mixing FA and LFS with a sodium-based alkali activator. The FA geopolymer had a compressive strength of 38.9 MPa with the optimum formulation of 8 M NaOH concentration, AS/AA ratio of 3, and AA ratio of 1.5. The compressive strength was affected more significantly by the amorphous content. The most influential factors affecting the properties of FA geopolymer were: AS/AA ratio > AA ratio > NaOH concentration. Replacing LFS led to very little (4.1%) increment in the compressive strength. The LFS had little contribution in supplying Si, Al and Ca for the formation of the N-A-S-H and C-A-S-H network. But LFS acted as a filler and improved the compactness of the FA geopolymer. The mechanical performance of FA/LFS geopolymer was not governed by the amorphous content like the FA geopolymer, as LFS addition contributed to increasing crystalline content. New crystalline phases of calcite and CSH due to the addition of LFS helped to retain the compressive strength of FA geopolymer. Nevertheless, the outcome of the study proved that LFS can be blended with FA to produce geopolymers without severe deterioration in mechanical strength. LFS can be potentially added in geopolymers as filler to produce geopolymer mortar.

View
Thumbnail Image
Publication

A sustainable photocatalytic fuel cell integrated photo-electro-Fenton hybrid system using KOH activated carbon felt cathodes for enhanced Amaranth degradation and electricity generation

2022-07-01 , Thor S.H. , Ho Li Ngee , Ong Soon An , Che Zulzikrami Azner Abidin , Heah Cheng Yong , Ong Y.P. , Yap K.L.

Photo-electro-Fenton (PEF) process was integrated with photocatalytic fuel cell (PFC) through the connection of electrodes and the cathodes were responsible for the acceptance of electrons. In this study, potassium hydroxide (KOH) was used to activate the carbon felt (CF) to improve the oxygen reduction reaction reactivity on cathodes for effective PFC integrated PEF hybrid system (PFC-PEF system) in Amaranth removal and electricity generation simultaneously. The results revealed that KOH activated CF cathodes had improved the electro-generation of hydrogen peroxide in both PFC and PEF and contributed to decolourisation efficiencies of 99.25% (PFC) and 96.10% (PEF). The maximum power density (4.218 μW cm−2) achieved by KOH activated CF cathode was 22% higher than that of pristine CF. The results revealed that air flow rate of 1000 mL min−1 favoured the generation of more reactive species for effective Amaranth degradation under the dissolved oxygen enrichment condition. The highest decolourisation rates were respectively achieved in PFC (0.5965 h−1) and PEF (0.2919 L mg−1 h−1) at air flow rate of 1000 mL min−1.

View
Thumbnail Image
Publication

Correlation of Thermal Conductivity Versus Bulk Density, Porosity and Compressive Strength of Metakaolin Geopolymer

2020-07-09 , Ain Jaya N. , Liew Yun Ming , Heah Cheng Yong , Mohd. Mustafa Al Bakri Abdullah

This paper investigates the correlation of thermal conductivity versus bulk density, porosity and compressive strength of metakaolin geopolymer for different mixing parameters (that are, alkali concentration, activator (AA) ratio and metakaolin/activator (MK/AA) ratio). Metakaolin was alkali-activated with NaOH and Na2SiO3 solution to produce geopolymer. Varying NaOH concentration (6M, 8M, 10M, 12 M and 14M), AA ratio (0.4, 0.6, 0.8, 1.0 and 1.2) and MK/AA ratio (0.6, 0.7, 0.8, 0.9 and 1.0) were used to study the effect on bulk density, porosity, compressive strength and thermal conductivity. Result showed that metakaolin geopolymer with maximum compressive strength (33 MPa), bulk density of 1680 kg/m3, porosity of 18% and thermal conductivity of 0.40 W/mK is achieved with alkali concentration of 10M, AA ratio of 1.0 and MK/AA ratio of 0.8. From the gradation analysis of the strength result, AA ratio is the most influential mixing parameter in determining the compressive strength. In contrast, MK/AA ratio significantly affected the thermal conductivity. From the Pearson correlation coefficient, TC had strong relationship with bulk density and porosity and poor relationship with compressive strength.

View