Rosalam Sarbatly - Academia.edu (original) (raw)

Papers by Rosalam Sarbatly

Applied chemical engineering, Mar 13, 2024

AIP Conference Proceedings, Dec 31, 2022

International Journal of Food Engineering, Sep 24, 2010

This study reveals the drying kinetics, specific heat and enthalpy of seaweed dried in the convec... more This study reveals the drying kinetics, specific heat and enthalpy of seaweed dried in the convective air drier. Comparison between convective hot air and sun drying process was also studied. At 50°C air temperature with 23.45 percent relative humidity and 1.55 ms-1air flow rate, it has been found that the moisture removal required 4 hours to reach moisture content of 19.66 percent wet basis with its drying rate at 0.28 × 10-3 kg water h-1. The data of drying rate showed that the drying process took place in the falling rate period. The specific heat and initial enthalpy were found to be 1.3842 kJkg-1°C-1 and 1672.69 kJkg-1, respectively. It was observed that the drying kinetics, specific heat, and enthalpy values vary significantly as functions of air temperature which seem to have more effect when compared to air flow rate and seaweed loading. Hence, the best method for seaweed drying was to use convective air system rather than sun drying because it required less drying time and has better drying efficiency.

Chemical Engineering and Processing, Apr 1, 2016

This work presents a study of the heat and mass transfer performance of desalination in a laborat... more This work presents a study of the heat and mass transfer performance of desalination in a laboratory-scale rectangular cross-flow flat-sheet membrane module by vacuum membrane distillation (VMD) experiments. Results show that the traditional Nusselt and Sherwood correlations, which are frequently employed in the membrane distillation

Materials Today: Proceedings, Mar 1, 2023

Journal of King Saud University: Engineering Sciences, 2015

Antioxidant activity and total phenolic content of an isolated Morinda citrifolia L. methanolic e... more Antioxidant activity and total phenolic content of an isolated Morinda citrifolia L. methanolic extract by using membrane separator were investigated. The extract of M. citrifolia L. fruit by methanol was separated into permeate and retentate by Polyethersulphone (PES). The effect of temperature in the range of 30-70 C, and pressure in the range of 0.5-1.5 bar on the antioxidant activity and total phenolic content was studied. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity exhibited a gradual increase in permeates' collection from membrane separation. The total phenolic content was also found to follow the same trend. The optimum magnitudes of DPPH radical scavenging activity and total phenolic content were found to be 55.60% and 43.18 mg GAE/10 gm of sample respectively

Springer eBooks, Feb 8, 2012

The integration of a membrane contactor with a photobioreactor serves two major purposes for the ... more The integration of a membrane contactor with a photobioreactor serves two major purposes for the mitigation of CO₂ by microalgae, i.e., to enhance the mass transfer and interfacial contact between two different phases and to increase the exchange process of CO₂-O₂ by microalgae in the photobioreactor. The membrane integrated with a photobioreactor for CO₂ mitigation by microalgae can be considered as a relatively new field, and only four or five related research efforts have been published in the literature, suggesting that a significant amount of work remains to be done in this field. In addition, all of the authors agreed that a membrane contactor is capable of achieving better mass transfer than the conventional approach of using a separation column in the gas-liquid separation process. One significant problem associated with using a membrane as a CO₂-O₂ gas exchanger is its susceptibility to pore fouling due to the micron-size cells of the microalgae. However, pore fouling can be prevented by using a hydrophobic membrane contactor and appropriate operating conditions, both of which are discussed in detail in this work.

Advanced Materials Research, Mar 1, 2012

Journal of Applied Sciences, Jun 15, 2011

ASM science journal, Dec 22, 2022

An upflow sand filter operated in incremental filtration rates (0.072, 0.181, 0.481 m 3 m-2 h-1) ... more An upflow sand filter operated in incremental filtration rates (0.072, 0.181, 0.481 m 3 m-2 h-1) was studied for turbidity, total suspended solids (TSS), ammonia (NH4), and total coliform removal rates. Each cycle lasted for 45 days. The filter bed was made of sand with 0.10 mm D10 and supported by 0.49 mm and 2.10 mm gravel with a total bed depth of 0.50 m. Turbidity removal was recorded above 80% in all cycles with a maximum concentration of 7.29 NTU. TSS removal was maintained at over 90%, with an average discharge of 4.77 mg/L in all cycles. The NH4 removal increased steadily to 91% for 0.072 m 3 m-2 h-1 and 93% for 0.181 m 3 m-2 h-1 filtration rate. The algal bloom occurrence at 0.481 m 3 m-2 h-1 filtration rate overloaded the system with NH4, declining the removal rate to 45%. Total coliform removal recorded an average of 99% in 0.072 m 3 m-2 h-1 , 89% in 0.181 m 3 m-2 h-1 , and 66% in 0.481 m 3 m-2 h-1. A high filtration rate resulted in a shorter contact time between pollutants and microorganisms within the filter bed, which reduces the removal efficiency. The Shearing effect was also experienced where the attachments of particles and bacteria were minimised.

IOP conference series, Sep 10, 2019

A tubular nanofiber membrane module is developed and tested in the seawater desalination by using... more A tubular nanofiber membrane module is developed and tested in the seawater desalination by using air-gap membrane desalination (AGMD). Meltblowing device is used to produce the nanofibers which are collected at a distance of 37 cm away from the tip of the spinneret. Results show that the flux varies almost constantly with the feed flow rates. The independence of the flux on the feed flow rates suggested that the meltblown nanofiber membrane is a dense membrane in which the volume of pores has been reduced and compacted significantly. The flux increases exponentially with the feed temperatures which obeys the Arrhenius relation. The quality of permeate is essentially improved by using the compacted nanofiber membrane. The rejection of the dissolved salts is more than 99.3%, in which the conductivity values of permeate ranged between 8 and 50 μS/cm.

Materials Today: Proceedings

IOP Conference Series: Materials Science and Engineering, 2021

A simple, small scale upflow sand filter was fabricated using a locally obtained sands at three d... more A simple, small scale upflow sand filter was fabricated using a locally obtained sands at three different rivers in Sabah, Malaysia: Liwagu River (SL), Tamparuli River (ST), and Kaingaran River (SK). The grain size, porosity, bulk density, particle density and sphericity of the sands were characterized to associate with the corresponding pressure drop across the sand bed. The highest pressure drop per unit length for SK, PT, and SL are 15.85 kPa m-1 at 0.747 m s-1 vs, 10.18 kPa m-1 at 0.352 m s-1 vs, and 9.24 kPa m-1 at 0.747 m s-1 vs, respectively. The pressure drop per unit length at different filter bed depth were plotted, and compared against three theoretical models of Ergun, Kozeny-Carman, and Fair and Hatch. By analyzing the experimental-theoretical comparison using RMSE and Chi-Test, prediction of pressure drop in an upflow sand filter is able to be predicted using the Kozeny-Carman equation preceding filter bed fluidization and subsequently Fair and Hatch’s equation after b...

IOP Conference Series: Earth and Environmental Science, 2016

Microalgae ability to utilise CO2 higher compared to terrestrial plant making it suitable for bio... more Microalgae ability to utilise CO2 higher compared to terrestrial plant making it suitable for biomass production and as CO2 utiliser. This could be one of many ways to preserve a safer and healthier environment with less air pollutant. For study purposes, CO2 usually transported to microalgae culture broth with the aid of membrane technology to prevent formation of large bubble and to accelerate the carbonation of microalgal media. However, membrane susceptible to accumulation of CO2, which can cause extreme acidic to microalgal media. This prevents microalgae to assimilate CO2. Thus, this study proposes correlations to prevent the extreme acidic: which represents the relationship of: (1) CO2 inlet and accumulation, (2) CO2 inlet and CO2 at the membrane-liquid interphase and (3) CO2 inlet and CO2 solubility in the media. The correlations were successfully validated with a deviation of less than 20% compared to the theoretical value.

2012 IEEE Business, Engineering & Industrial Applications Colloquium (BEIAC), 2012

Palm oil industry contributes significantly to Malaysian economy. However, there seem to be very ... more Palm oil industry contributes significantly to Malaysian economy. However, there seem to be very few studies conducted on improving the palm oil production process. Specifically, there is seemed to be lacked of studies on the application of simulation modelling in improvement activities conducted on palm oil mills. This study addressed this gap by demonstrating the application of simulation modelling in

Journal of Applied Sciences, 2011

ABSTRACT This work focused on characterisation of local isolate microalgae strain as a biofuel fe... more ABSTRACT This work focused on characterisation of local isolate microalgae strain as a biofuel feedstock. Two well-established, nonlocal isolates, Chlorella emersonii and Chlorella protothecoides were also studied with the same consideration for comparison. The local strain is capable of reproducing up to 1.65 x10 6 cell/ml daily, which is about 1.3 to 2 times greater than the other strains and could survive for longer periods without additional nutrients. Phototrophic culture of this microalga resulted in 58% lipid production on dry weight basis. The mixotrophic production, on the other hand, depends on glucose concentrations whereas 1g/l of glucose is capable of producing about 55% lipid content on dry weight basis. Fatty acid analysis shows that palmitic and oleic acid dominated the lipid content making it suitable to be used as biofuel specifically biodiesel feedstock. In addition, the energy content of dried biomass was 23MJ/kg, which is comparable to well-established biomass for biofuel productions.