Conversion of coconut waste into cost effective adsorbent for Cu(II) and Ni(II) removal from aqueous solutions

Abdul Rahman Abdul Rahim,Iswarya,Khairiraihanna Johari,Nasir Shehzad,Norasikin Saman,Hanapi Mat 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.4

Desiccated coconut waste (DCW) is an agricultural waste that originates from the coconut milk processing industry. In this study, it was utilized for the removal of copper (Cu(II)) and nickel (Ni(II)) via adsorption process. The physicochemical characterization of the DCW adsorbent shows that the adsorbent have a surface area of 6.63 ㎡/g, have high elemental carbon content and existences of important functional groups on its surface. The adsorptive capability of DCW adsorbent in removing the heavy metal were conducted in batch studies. DCW adsorbent performed highest Ni(II) and Cu(II) adsorption capacity at pH 6, where equilibrium is achieved at 450 minutes. The kinetic analysis showed the adsorption agreed with pseudo-second order kinetic model, indicating the Cu(II) and Ni(II) adsorption were a chemical adsorption, limited by the film diffusion. The DCW adsorbent still retained its effective adsorption capacity after 2 adsorption-desorption cycles, which is one of the excellent criteria of a good adsorbent for an adsorption process.

Isothermal, kinetic, thermal, and economic characteristics of NaOH-modified charred–desiccated coconut waste as adsorbent for lead (II) in water phase

Abdul Rahman Abdul Rahim,Khairiraihanna Johari,Nurul Ekmi Rabat,Murid Hussain,Nasir Shezad,Young-Kwon Park 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.127 No.-

In this study, charred–desiccated coconut waste was treated with several chemicals, such as NaOH,NaOCl, H2O2, and HNO3, to prepare chemically modified adsorbents. Fourier transform infrared spectroscopyrevealed that chemical modification enhanced the surface chemistry of the adsorbent by introducingnew functional groups and increasing their concentration. The chemically modified adsorbentshad lower surface areas of 0.13–17.36 m2/g, which were substantially lower than that of the pristineadsorbent. Regardless of the surface area, all modified adsorbents exhibited higher Pb(II) adsorptioncapacities, wherein that of desiccated coconut-waste char (DCWC)-NaOH was the highest, with a removalefficiency of 96% (Q = 29.854 mg/g) for an adsorption time of 1 min. The equilibrium and kinetic data forthe DCWC-NaOH adsorbent best fit the Freundlich isotherm and pseudo-second-order kinetic models,respectively, with a maximum monolayer adsorption capacity of 1666.67 mg/g. The adsorption of Pb(II) ions was an exothermic process, with an optimum temperature of 40 C. Compared to existing commercialadsorbents, the proposed adsorbent was highly regenerable and considerably low-cost, showingpromising potential for commercial applications.

Effect of solvent and calcination process on physicochemical features of silica nanocapsule for CO₂ capture

Abdul Rahman Abdul Rahim,Khairiraihanna Johari,Murid Hussain 대한환경공학회 2024 Environmental Engineering Research Vol.29 No.6

Silica nanocapsules (SiNC) have gained considerable interest in their application as adsorbents due to its excellent physical structure and surface chemistry. The SiNC were synthesised via emulsion technique, whereby the effect of different solvents and calcination process were investigated. Diethyl ether as a solvent produced SiNC with the biggest surface area, 644 ㎡/g, followed by toluene and ethanol, 575 and 533 ㎡/g, respectively. The calcined SiNC had bigger surface area and pore volume, but smaller pore size as compared to their non-calcined counterparts. Diethyl ether and toluene as solvents produced SiNC with capsules or hollowed-core morphological structure, whereas by using ethanol, the SiNC was of solid core. The spectral analysis showed that the SiNC were of similar characteristics, whereby the ethanol-based SiNC had more intense hydroxyl (-OH) peaks and diethyl ether and toluene had an extra -CH₃ peak. The carbon dioxide (CO₂) adsorption measurement study showed that toluene-based SiNC performed the highest CO₂ adsorption capacity (Q = 2.59 mmol/g), followed by diethyl ether-based (1.45 mmol/g) and ethanol-based, (1.28 mmol/g). The sufficiently competent CO₂ adsorption capacity of the SiNC combined with their excellent physicochemical characteristics indicated their promising prospects for application as an adsorbent in CO₂ adsorption.

Arterial Compliance and Vitamin E Blood Levels with a Self Emulsifying Preparation of Tocotrienol Rich Vitamin E

Rasool, Aida Hanum Ghulam,Rahman, Abd Rashid Abd.,Yuen, Kah Hay,Wong, Abdul Rahim 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.9

The tocotrienol vitamin E has potent antioxidant property, however absorption is low due to high lipid solubility. A self emulsifying preparation of tocotrienol rich vitamin E (SF-TRE) had been reported to increase their bioavailability. This randomized, placebo controlled, blinded end point clinical study aimed to determine the effects of 50, 100 and 200 mg daily of SF-TRE and placebo for two months on arterial compliance and vitamin E blood levels. Assessment of arterial compliance by carotid femoral pulse wave velocity (PWV) and augmentation index (AI), plasma vitamin E, serum total cholesterol and low density lipoprotein cholesterol were taken before and after 2 months' treatment in 36 healthy males. Un-supplemented tocotrienol levels were low, after treatment, all SF-TRE treated groups had significantly higher plasma $\alpha$, $\delta$ and $\delta$ tocotrienol concentrations compared to placebo. Augmentation index change from baseline to end of treatment for groups placebo, 50, 100, and 200 mg were $2.22{\pm}1.54$, $-6.59{\pm}2.84$, $-8.72{\pm}3.77$, and $-6.27{\pm}2.67%$ respectively (p=0.049, 0.049, and 0.047 respectively). Groups 100 and 200 mg showed significant improvement after treatment with pulse wave velocity reductions of 0.77 m/s and 0.65 m/s respectively (p=0.007 and p=0.002). There was no effect of SF-TRE on serum lipids. We conclude that there was a trend towards improvement in arterial compliance with 2 months' of SF-TRE.

Spatial Analysis of Colorectal Cancer Cases in Kuala Lumpur

Shah, Shamsul Azhar,Neoh, Hui-Min,Syed Abdul Rahim, Syed Sharizman,Azhar, Zahir Izuan,Hassan, Mohd Rohaizat,Safian, Nazarudin,Jamal, Rahman Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Background: In Malaysia, data from the Malaysian Health Ministry showed colorectal cancer (CRC) to be the second most common type of cancer in 2007-2009, after breast cancer. The same was apparent after looking at males and females cases separately. In the present study, the Geographic Information System (GIS) was employed to describe the distribution of CRC cases in Kuala Lumpur (KL), Malaysia, according to socio-demographic factors (age, gender, ethnicity and district). Materials and Methods: This retrospective review concerned data for patients diagnosed with colorectal cancer in the years 1995 to 2011 collected from the Wilayah Persekutuan Health Office, taken from the cancer notification form (NCR-2), and patient medical records from the Surgical Department, Universiti Kebangsaan Malaysia Medical Centre (UKMMC). A total of 146 cases were analyzed. All the data collected were analysed using ArcGIS version 10.0 and SPSS version 19.0. Results: Patients aged 60 to 69 years accounted for the highest proportion of cases (34.2%) and males slightly predominated 76 (52.1%), Chinese had the highest number of registered cases at 108 (74.0%) and staging revealed most cases in the 3rd and 4th stages. Kernel density analysis showed more cases are concentrated up in the northern area of Petaling and Kuala Lumpur subdistricts. Spatial global pattern analysis by average nearest neighbour resulted in nearest neighbour ratio of 0.75, with Z-score of -5.59, p value of <0.01 and the z-score of -5.59. Spatial autocorrelation (Moran's I) showed clustering significant with p<0.01, Z score 3.14 and Moran's Index of 0.007. When mapping clusters with hotspot analysis (Getis-Ord Gi), hot and cold spots were identified. Hot spot areas fell on the northeast side of KL. Conclusions: This study demonstrated significant spatial patterns of cancer incidence in KL. Knowledge about these spatial patterns can provide useful information to policymakers in the planning of screening of CRC in the targeted population and improvement of healthcare facilities to provide better treatment for CRC patients.

Arterial Compliance and Vitamin E Blood Levels with a Self Emulsifying Preparation of Tocotrienol Rich Vitamin E

Aida Hanum Ghulam Rasool,Abd. Rashid Abd. Rahman,Kah Hay Yuen,Abdul Rahim Wong 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.9

The tocotrienol vitamin E has potent antioxidant property, however absorption is low due to high lipid solubility. A self emulsifying preparation of tocotrienol rich vitamin E (SF-TRE) had been reported to increase their bioavailability. This randomized, placebo controlled, blinded end point clinical study aimed to determine the effects of 50, 100 and 200 mg daily of SF-TRE and placebo for two months on arterial compliance and vitamin E blood levels. Assessment of arterial compliance by carotid femoral pulse wave velocity (PWV) and augmentation index (AI), plasma vitamin E, serum total cholesterol and low density lipoprotein cholesterol were taken before and after 2 months’ treatment in 36 healthy males. Un-supplemented tocotrienol levels were low, after treatment, all SF-TRE treated groups had significantly higher plasma α, δ and δ tocotrienol concentrations compared to placebo. Augmentation index change from baseline to end of treatment for groups placebo, 50, 100, and 200 mg were 2.22±1.54, -6.59±2.84, -8.72±3.77, and -6.27±2.67% respectively (p=0.049, 0.049, and 0.047 respectively). Groups 100 and 200 mg showed significant improvement after treatment with pulse wave velocity reductions of 0.77 m/s and 0.65 m/s respectively (p=0.007 and p=0.002). There was no effect of SF-TRE on serum lipids. We conclude that there was a trend towards improvement in arterial compliance with 2 months’ of SF-TRE.