Kah Chun Ho | Taylor's University College (original) (raw)

Papers by Kah Chun Ho

Journal of Applied Membrane Science & Technology

It is worth noticing that structure of nanomaterials affects the membrane performance, however, t... more It is worth noticing that structure of nanomaterials affects the membrane performance, however, the effect of diameter of multiwalled carbon nanotubes (MWCNTs) has not been discussed in the past. This research aims to investigate the effect of diameter of MWCNTs on the performance of graphene oxide (GO)/ MWCNTs nanocomposite membrane for methyl orange dye removal. MWCNTs with different diameters (12-15 nm, 30-50 nm) with the same length (< 10 µm) are used to synthesize the nanocomposite membrane. The characteristics of the synthesized nanocomposite membrane were determined by surface hydrophilicity, pore size and porosity, zeta potential, and Fourier-transfer infrared (FTIR) spectroscopy. Besides, the membrane performance was evaluated by the water permeability test, dye rejection test, and antifouling test. The result showed that pure MWCNTs (30-50 nm) nanocomposite membrane (M2b) has the best performance among the synthesized membrane. The dye rejection of M2b membrane reached ...

Integrated Environmental Technologies for Wastewater Treatment and Sustainable Development

Journal of Cleaner Production, 2022

Nanofiltration (NF) membrane is a class of pressure-driven membrane, which is an intermediate of ... more Nanofiltration (NF) membrane is a class of pressure-driven membrane, which is an intermediate of ultrafiltration membrane and reverse osmosis (RO). With the pore size ranging from 0.1 to 1 nm (equivalent to molecular weight cut-off of 200–1000 Da), the NF membrane has a high removal rate for multivalent salt ions and organic solutes which have a molecular weight larger than 200 Da. Hence, the NF membrane is suitable to be used to remove hardness, heavy metals, and large organic matter such as dyes. However, it has a low rejection of monovalent ions and neutral solutes with a molecular weight below 200, which can be removed only through RO membranes.

Membrane Separation Principles and Applications, 2019

Abstract The membrane bioreactor (MBR) has become an established hybrid or integrated membrane pr... more Abstract The membrane bioreactor (MBR) has become an established hybrid or integrated membrane process for various applications, especially for industrial and municipal wastewater treatments. Recent advances in membrane technology and system design for MBRs have resulted in wide usage of MBRs. Various types of materials have been used for producing membranes that have been used successfully in MBRs. These membranes were produced using various fabrication techniques including nonsolvent induced phase separation (NIPS), and melt spinning cold stretching (MSCS), track-etched, and electrospinning. The major characteristics of the membranes that are important are related to the pore size and porosity, surface roughness, hydrophilicity, and surface charge. Various methods have been used to characterize these properties. Within the system itself, the design and optimization of the biological and membrane processes are very important to ensure that the system is operational and cost-effective. Due to these advances, MBRs have found applications in many sectors including those for municipal wastewater, leachate treatment, dye and textile, petrochemical, food and beverage, and pharmaceutical. This chapter discusses all the above issues in more detail.

Particulate Science and Technology, 2021

Abstract The objective of this study is to synthesize QD-embedded molecularly imprinted membranes... more Abstract The objective of this study is to synthesize QD-embedded molecularly imprinted membranes (MIMs) with 2-mercaptoethanol-capped manganese-doped zinc sulfide quantum dots (ME-capped Mn-doped ZnS QDs) through chemical precipitation followed by surface molecular imprinting. For the synthesis of the MIMs, the weight of ME-capped Mn-doped ZnS QDs was first manipulated, followed by their characterization through transmission electron microscopy (TEM), zeta potential, hydrodynamic particle size, particle size distribution, and Fourier-transform infrared spectroscopy (FTIR). The resultant MIM was characterized by fluorescence intensity and showed an emission peak of 600 nm with an excitation wavelength of 300 nm. Besides, increments in QDs were found to elevate the fluorescence intensity of the MIM, contributing to an improved fluorescence quantum yield. This article indicates that molecularly-imprinted QD-based sensors offer promising biomedical potential in diagnoses and treatment.

Science of The Total Environment, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Journal of Water Process Engineering, 2020

This study aimed to evaluate several potential candidates of single disinfection/disinfectant uni... more This study aimed to evaluate several potential candidates of single disinfection/disinfectant units and integrated disinfection systems in treating sewage effluent to obtain non-potable water, within a techno-economic analysis framework. Eight candidates of commercially available disinfection units and integrated disinfection systems were selected to be examined under the techno-economic analysis by comparison amongst the sewerage effluent. There were 4 types of treatment processes represented amongst the single disinfection units (Single): ultraviolet (UV), chlorination, microfiltration (MF), and ultrafiltration (UF). Within these processes, MF and UF both were represented twice by HVLP00010 and PVDF021 M (MF membranes); and by PVDF1001 M and PES20kDa (UF membranes). Whereas, for integrated disinfection systems (Integrated), UV disinfection and chlorination act as the primary disinfection unit, with MF/UF, Enviromulti-media (EMM) adsorption, or granular activated carbon (GAC) adsorption integrated as the pre-treatment unit. Two design capacities for water recovery-100 m³/day (to represent a pilot-scale reproduction) and 5000 m 3 /day (to represent an industrial-scale reproduction) were defined to analyze and compare the cost effectiveness between single disinfection units and integrated disinfection systems chosen in this study. Amongst the studied setups, single chlorination unit and EMM-UV integrated disinfection system were the two most economical configurations to regenerate treated water for restricted applications. Whereas, the single PVDF1001 M UF membrane filtration unit was ultimately suggested as the most economic and viable technology for unrestricted water reuse purpose at both design capacities, considering the estimated cost at Malaysia currency, RM 0.50/m³ and RM 0.10/m³ for 100 m³/day and 5000 m³/day design capacity, respectively.

Journal of Water Process Engineering, 2020

This study explores a green-synthesis method for developing biodegradable cellulose membranes usi... more This study explores a green-synthesis method for developing biodegradable cellulose membranes using cellulose extracted from oil palm empty fruit bunch (OPEFB). The OPEFB-derived cellulose membranes were formulated with two different types of solvents and at different cellulose-to polyvinylidene fluoride (PVDF) ratios. The performance of OPEFB-derived cellulose membranes in treating dye wastewater was evaluated. Among different membrane formulations, the M2 OPEFB-derived membranes produced using 1-methyl-2-pyrrolidone (NMP) and cellulose content of 3 wt% was found to be optimal, given its comparatively higher permeate flux (132.57-158.06 L/m 2 h) and methylene blue (MB) dye rejection (13.13-36.16 %). Besides, the M2(b) OPEFBderived cellulose membrane with cellulose content of 3 wt% and a cellulose:PVDF ratio of 96:4 was found to be the optimum membrane formulation, given its lowest surface roughness, high permeate flux due to large membrane pore sizes, and high membrane porosity without compromising its performance on MB dye rejection. The exploration of OPEFB-derived cellulose membranes would ensure cost-effective and abundantly available raw materials for dye wastewater treatment.

Jurnal Kejuruteraan, 2017

Severe water shortage caused by El-Nino has caused life-threatening drought conditions globally. ... more Severe water shortage caused by El-Nino has caused life-threatening drought conditions globally. This natural disaster has put millions of lives at risk and forcing the people to search for waster. However, the water scarcity problem was not just limited to the countries that were strike by El-Nino. Poor water management and climate change were bringing droughts to Asia and the Pacific. The water scarcity worldwide has recently reached the alarming rate and received the greatest attention among the people. Membrane technology is an innovative technology which has proven to be effective and efficient for water and wastewater treatment. Therefore, membrane technology has high potential to be employed for the treatment of lake water, mine water, and tube well water in increasing the fresh water production for reuse purpose. The objective of this work is to investigate the potential of membrane technology for treating the lake water, mine water, and tube well water. A laboratory bench-scale dead-end test rig was used in this study to evaluate the performance of commercial flatsheet nanofiltration (NF)-NF270 and reverse osmosis (RO)-BW30 membranes. Both source water and treated water were analysed based on chemical oxygen demand (COD), ammonia nitrogen (NH 3-N), colour, total suspended solid (TSS), pH, and temperature. In order to prove the reuse concept of membrane technology, the permeate water quality after the membrane filtration process was compared with National Water Quality Standard (NWQS) of Malaysia. The results from this study shown that the permeate water filtered by NF270 and BW30 membranes were able to meet the NWQS Class III, which was suitable to recycled for livestock drinking and irrigation purposes.

Jurnal Teknologi

It is reported that the membrane properties can be enhanced by nanomaterials. However, agglomerat... more It is reported that the membrane properties can be enhanced by nanomaterials. However, agglomeration will occur due to the overdose of nanomaterials subsequently deteriorating membrane performance. The project aims to investigate the effect of concentration of cabon nanomaterials: multiwalled carbon nanotubes (MWCNTs) and graphene oxide (GO), on nanocomposite membrane for methyl blue (MB) dye removal. The GO/MWCNTs nanocomposite membranes were synthesized using direct blending method with three concentrations (0.2, 0.5, and 1 wt.%). The synthesized membrane was characterized by surface hydrophilicity, pore size and porosity, surface charge, functional group, and surface morphology. Besides, the performance of the synthesized membrane was evaluated by water permeability test, dye rejection test, and antifouling test. The result shows that the surface hydrophilicity was enhanced when the concentration of nanomaterials increased up to 0.2 wt%. However, higher concentration of nanomater...

Journal of Applied Membrane Science & Technology

It is worth noticing that structure of nanomaterials affects the membrane performance, however, t... more It is worth noticing that structure of nanomaterials affects the membrane performance, however, the effect of diameter of multiwalled carbon nanotubes (MWCNTs) has not been discussed in the past. This research aims to investigate the effect of diameter of MWCNTs on the performance of graphene oxide (GO)/ MWCNTs nanocomposite membrane for methyl orange dye removal. MWCNTs with different diameters (12-15 nm, 30-50 nm) with the same length (< 10 µm) are used to synthesize the nanocomposite membrane. The characteristics of the synthesized nanocomposite membrane were determined by surface hydrophilicity, pore size and porosity, zeta potential, and Fourier-transfer infrared (FTIR) spectroscopy. Besides, the membrane performance was evaluated by the water permeability test, dye rejection test, and antifouling test. The result showed that pure MWCNTs (30-50 nm) nanocomposite membrane (M2b) has the best performance among the synthesized membrane. The dye rejection of M2b membrane reached ...

Integrated Environmental Technologies for Wastewater Treatment and Sustainable Development

Journal of Cleaner Production, 2022

Nanofiltration (NF) membrane is a class of pressure-driven membrane, which is an intermediate of ... more Nanofiltration (NF) membrane is a class of pressure-driven membrane, which is an intermediate of ultrafiltration membrane and reverse osmosis (RO). With the pore size ranging from 0.1 to 1 nm (equivalent to molecular weight cut-off of 200–1000 Da), the NF membrane has a high removal rate for multivalent salt ions and organic solutes which have a molecular weight larger than 200 Da. Hence, the NF membrane is suitable to be used to remove hardness, heavy metals, and large organic matter such as dyes. However, it has a low rejection of monovalent ions and neutral solutes with a molecular weight below 200, which can be removed only through RO membranes.

Membrane Separation Principles and Applications, 2019

Abstract The membrane bioreactor (MBR) has become an established hybrid or integrated membrane pr... more Abstract The membrane bioreactor (MBR) has become an established hybrid or integrated membrane process for various applications, especially for industrial and municipal wastewater treatments. Recent advances in membrane technology and system design for MBRs have resulted in wide usage of MBRs. Various types of materials have been used for producing membranes that have been used successfully in MBRs. These membranes were produced using various fabrication techniques including nonsolvent induced phase separation (NIPS), and melt spinning cold stretching (MSCS), track-etched, and electrospinning. The major characteristics of the membranes that are important are related to the pore size and porosity, surface roughness, hydrophilicity, and surface charge. Various methods have been used to characterize these properties. Within the system itself, the design and optimization of the biological and membrane processes are very important to ensure that the system is operational and cost-effective. Due to these advances, MBRs have found applications in many sectors including those for municipal wastewater, leachate treatment, dye and textile, petrochemical, food and beverage, and pharmaceutical. This chapter discusses all the above issues in more detail.

Particulate Science and Technology, 2021

Abstract The objective of this study is to synthesize QD-embedded molecularly imprinted membranes... more Abstract The objective of this study is to synthesize QD-embedded molecularly imprinted membranes (MIMs) with 2-mercaptoethanol-capped manganese-doped zinc sulfide quantum dots (ME-capped Mn-doped ZnS QDs) through chemical precipitation followed by surface molecular imprinting. For the synthesis of the MIMs, the weight of ME-capped Mn-doped ZnS QDs was first manipulated, followed by their characterization through transmission electron microscopy (TEM), zeta potential, hydrodynamic particle size, particle size distribution, and Fourier-transform infrared spectroscopy (FTIR). The resultant MIM was characterized by fluorescence intensity and showed an emission peak of 600 nm with an excitation wavelength of 300 nm. Besides, increments in QDs were found to elevate the fluorescence intensity of the MIM, contributing to an improved fluorescence quantum yield. This article indicates that molecularly-imprinted QD-based sensors offer promising biomedical potential in diagnoses and treatment.

Science of The Total Environment, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Journal of Water Process Engineering, 2020

This study aimed to evaluate several potential candidates of single disinfection/disinfectant uni... more This study aimed to evaluate several potential candidates of single disinfection/disinfectant units and integrated disinfection systems in treating sewage effluent to obtain non-potable water, within a techno-economic analysis framework. Eight candidates of commercially available disinfection units and integrated disinfection systems were selected to be examined under the techno-economic analysis by comparison amongst the sewerage effluent. There were 4 types of treatment processes represented amongst the single disinfection units (Single): ultraviolet (UV), chlorination, microfiltration (MF), and ultrafiltration (UF). Within these processes, MF and UF both were represented twice by HVLP00010 and PVDF021 M (MF membranes); and by PVDF1001 M and PES20kDa (UF membranes). Whereas, for integrated disinfection systems (Integrated), UV disinfection and chlorination act as the primary disinfection unit, with MF/UF, Enviromulti-media (EMM) adsorption, or granular activated carbon (GAC) adsorption integrated as the pre-treatment unit. Two design capacities for water recovery-100 m³/day (to represent a pilot-scale reproduction) and 5000 m 3 /day (to represent an industrial-scale reproduction) were defined to analyze and compare the cost effectiveness between single disinfection units and integrated disinfection systems chosen in this study. Amongst the studied setups, single chlorination unit and EMM-UV integrated disinfection system were the two most economical configurations to regenerate treated water for restricted applications. Whereas, the single PVDF1001 M UF membrane filtration unit was ultimately suggested as the most economic and viable technology for unrestricted water reuse purpose at both design capacities, considering the estimated cost at Malaysia currency, RM 0.50/m³ and RM 0.10/m³ for 100 m³/day and 5000 m³/day design capacity, respectively.

Journal of Water Process Engineering, 2020

This study explores a green-synthesis method for developing biodegradable cellulose membranes usi... more This study explores a green-synthesis method for developing biodegradable cellulose membranes using cellulose extracted from oil palm empty fruit bunch (OPEFB). The OPEFB-derived cellulose membranes were formulated with two different types of solvents and at different cellulose-to polyvinylidene fluoride (PVDF) ratios. The performance of OPEFB-derived cellulose membranes in treating dye wastewater was evaluated. Among different membrane formulations, the M2 OPEFB-derived membranes produced using 1-methyl-2-pyrrolidone (NMP) and cellulose content of 3 wt% was found to be optimal, given its comparatively higher permeate flux (132.57-158.06 L/m 2 h) and methylene blue (MB) dye rejection (13.13-36.16 %). Besides, the M2(b) OPEFBderived cellulose membrane with cellulose content of 3 wt% and a cellulose:PVDF ratio of 96:4 was found to be the optimum membrane formulation, given its lowest surface roughness, high permeate flux due to large membrane pore sizes, and high membrane porosity without compromising its performance on MB dye rejection. The exploration of OPEFB-derived cellulose membranes would ensure cost-effective and abundantly available raw materials for dye wastewater treatment.

Jurnal Kejuruteraan, 2017

Severe water shortage caused by El-Nino has caused life-threatening drought conditions globally. ... more Severe water shortage caused by El-Nino has caused life-threatening drought conditions globally. This natural disaster has put millions of lives at risk and forcing the people to search for waster. However, the water scarcity problem was not just limited to the countries that were strike by El-Nino. Poor water management and climate change were bringing droughts to Asia and the Pacific. The water scarcity worldwide has recently reached the alarming rate and received the greatest attention among the people. Membrane technology is an innovative technology which has proven to be effective and efficient for water and wastewater treatment. Therefore, membrane technology has high potential to be employed for the treatment of lake water, mine water, and tube well water in increasing the fresh water production for reuse purpose. The objective of this work is to investigate the potential of membrane technology for treating the lake water, mine water, and tube well water. A laboratory bench-scale dead-end test rig was used in this study to evaluate the performance of commercial flatsheet nanofiltration (NF)-NF270 and reverse osmosis (RO)-BW30 membranes. Both source water and treated water were analysed based on chemical oxygen demand (COD), ammonia nitrogen (NH 3-N), colour, total suspended solid (TSS), pH, and temperature. In order to prove the reuse concept of membrane technology, the permeate water quality after the membrane filtration process was compared with National Water Quality Standard (NWQS) of Malaysia. The results from this study shown that the permeate water filtered by NF270 and BW30 membranes were able to meet the NWQS Class III, which was suitable to recycled for livestock drinking and irrigation purposes.

Jurnal Teknologi

It is reported that the membrane properties can be enhanced by nanomaterials. However, agglomerat... more It is reported that the membrane properties can be enhanced by nanomaterials. However, agglomeration will occur due to the overdose of nanomaterials subsequently deteriorating membrane performance. The project aims to investigate the effect of concentration of cabon nanomaterials: multiwalled carbon nanotubes (MWCNTs) and graphene oxide (GO), on nanocomposite membrane for methyl blue (MB) dye removal. The GO/MWCNTs nanocomposite membranes were synthesized using direct blending method with three concentrations (0.2, 0.5, and 1 wt.%). The synthesized membrane was characterized by surface hydrophilicity, pore size and porosity, surface charge, functional group, and surface morphology. Besides, the performance of the synthesized membrane was evaluated by water permeability test, dye rejection test, and antifouling test. The result shows that the surface hydrophilicity was enhanced when the concentration of nanomaterials increased up to 0.2 wt%. However, higher concentration of nanomater...