Effect of phosphate concentration, anions, heavy metals, and organic matter on phosphate adsorption from wastewater using anodized iron oxide nanoflakes

Afridi, Muhammad Naveed,Lee, Won-Hee,Kim, Jong-Oh Elsevier 2019 Environmental research Vol.171 No.-

<P><B>Abstract</B></P> <P>Phosphorus is a necessary nutrient for the growth and survival of living beings. Nevertheless, an oversupply of phosphorus in wastewater results in eutrophication. Therefore, its removal from wastewater is important. However, coexisting components, such as anions, heavy metals, and organic matter, might inhibit the phosphate-adsorption mechanism by competing for the active surface sites of the adsorbent. In this study, iron oxide nanoflakes (INFs) were fabricated on iron foil via anodization. The rate of phosphate adsorption from wastewater onto INFs in the presence of three different coexisting components—anions, heavy metals, and organic matter—was evaluated. The morphology of the INFs was analyzed by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy. The phosphate adsorption equilibrium time using INFs was found to be 1 h. The Elovich model (R<SUP>2</SUP> > 0.99) and the Langmuir model (R<SUP>2</SUP> >0.95) respectively provided the best description of the adsorption kinetics and isotherm, suggesting the chemisorption nature of adsorption. The estimated adsorption capacity of the INFs was 21.5 mg-P g<SUP>–1</SUP>. The effect of anions (chloride, sulfate, nitrate, and carbonate) and heavy metals (Cd, As, Cr, and Pb) was studied at three different molar ratios (0.5:1, 1:1, and 1.5:1). The effect of different types of organic matter, such as citric acid, humic acid, and oxalic acid at concentrations of 100 and 200 mg L<SUP>–1</SUP>, was also examined. In five regeneration cycles, the total amount of phosphate adsorbed and desorbed, and the recovery percentage were 6.51 mg-P g<SUP>–1</SUP>, 5.16 mg-P g<SUP>–1</SUP>, and 79.24%, respectively.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Iron oxide nanoflakes were synthesized via an electrochemical anodization. </LI> <LI> Effect of time, phosphate concentration, and coexisting components were tested. </LI> <LI> Phosphate uptake process was followed by the Elovich model. </LI> <LI> The maximum phosphate adsorption capacity of INF was 21.5 mg-P g<SUP>–1</SUP>. </LI> <LI> Effect of coexisting organic matter is higher followed by heavy metals and anions. </LI> </UL> </P>

문예 마당 : 수필; 유학생의 눈으로 본 한국사회

Lmran Afridi,Hanifi Baris,Kshetrimayum Onil 5·18 기념재단 2010 아시아저널 Vol.20 No.-

Application of synthesized bovine serum albumin-magnetic iron oxide for phosphate recovery

Muhammad Naveed Afridi,Wonhee Lee,Jong-Oh Kim 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.86 No.-

Phosphorous is an essential nutrient that is widely used as a fertilizer in agriculture. However, itsincreased discharge from agricultural runoff contributes to eutrophication, necessitating its removalfrom wastewater. Adsorption is one of several treatment processes for this purpose. In this study, bovineserum albumin-magnetic iron oxide (BSA-MIO) was successfully synthesized using the co-precipitationmethod. Its morphology was characterized byfield emission scanning electron microscopy, energydispersive X-ray spectroscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. Differentparameters that affect adsorption, such as initial phosphate concentration, reaction time, adsorbentdosage, pH, coexisting anions, and temperature, were investigated. The results showed that phosphateadsorption increased with reaction time and temperature while it decreased with an increase in solutionpH. The phosphate adsorption equilibrium time using BSA-MIO was 1 h. The estimated maximumadsorption capacity of BSA-MIO was 20.7 mg P g 1. Moreover, the pseudo-second-order model(R2 > 0.99) and Langmuir model (R2 > 0.99) elucidated the better description of the adsorption kineticsand isotherm, respectively, thereby suggesting the chemisorption nature of adsorption. The coexistinganions (NO3, Cl , SO42 , and CO32 ) showed no significant effect on phosphate adsorption. Moreover,the adsorbed phosphate was successfully desorbed using different concentrations and combinations ofNaOH and NaCl. © 2020 The Korean

Entropy Generation Minimization in MHD Boundary Layer Flow over a Slendering Stretching Sheet in the Presence of Frictional and Joule Heating

Muhammad Idrees Afridi,Muhammad Qasim,Ilyas Khan 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.9

In the present paper, we study the entropy analysis of boundary layer ow over a slender stretching sheet under the action of a non uniform magnetic field that is acting perpendicular to the ow direction. The effects of viscous dissipation and Joule heating are included in the energy equation. Using similarity transformation technique the momentum and thermal boundary layer equations to a system of nonlinear differential equations. Numerical solutions are obtained using the shooting and fourth-order Runge-Kutta method. The expressions for the entropy generation number and Bejan number are also obtained using a suggested similarity transformation. The main objective of this article is to investigate the effects of different governing parameters such as the magnetic parameter (M2), Prandtl number (Pr), Eckert number (Ec), velocity index parameter (m), wall thickness parameter (ff), temperature difference parameter ( ), entropy generation number (Ns) and Bejan number (Be). All these effects are portrayed graphically and discussed in detail. The analysis reveals that entropy generation reduces with decreasing wall thickness parameter and increasing temperature difference between the stretching sheet and the uid outside the boundary layer. The viscous and magnetic irreversibilities are dominant in the vicinity of the stretching surface.

Photocatalytic degradation performance of various types of modified TiO₂ against nitrophenols in aqueous systems

Fatima, Rida,Afridi, Muhammad Naveed,Kumar, Vanish,Lee, Jechan,Ali, Imran,Kim, Ki-Hyun,Kim, Jong-Oh Elsevier 2019 JOURNAL OF CLEANER PRODUCTION Vol.231 No.-

<P><B>Abstract</B></P> <P>Nitrophenols are used extensively in the chemical, pharmaceutical, and pesticide industries. Recently, water pollution caused by nitrophenols has gained worldwide attention. Significant efforts have been made over the past years to develop effective treatment options for the removal of nitrophenols in aqueous phase. Photocatalysis using titanium dioxide (TiO<SUB>2</SUB>) is regarded as one of the most effective options to degrade nitrophenols in contaminated water. This review deals with the performance of TiO<SUB>2</SUB> photocatalysis for the degradation of nitrophenols and related mechanisms. The performance of TiO<SUB>2</SUB> photocatalysts is assessed by comparing basic performance metrics such as quantum yields and reaction rates before and after modification (e.g., pristine vs. modified forms). Results suggest that TiO<SUB>2</SUB>-based photocatalysis is a promising treatment option for degrading nitrophenol.</P>

Clove and Its Active Compound Attenuate Free Fatty Acid-Mediated Insulin Resistance in Skeletal Muscle Cells and in Mice

Safina Ghaffar,Shabbir Khan Afridi,Meha Fatima Aftab,Munazza Murtaza,Rahman M. Hafizur,Sara Sara,Sabira Begum,Rizwana Sanaullah Waraich 한국식품영양과학회 2017 Journal of medicinal food Vol.20 No.4

Several reports indicate anti-hyperglycemic effects of Syzygium aromaticum. In the present study, we report for the first time that clove extract (SAM) and its compound nigricin (NGC) decreases free fatty acid-mediated insulin resistance in mouse myoblasts. In addition, NGC was able to diminish insulin resistance in a diabetic mouse model. We observed that SAM and its compound NGC exhibited significant antioxidant activity in murine skeletal muscle cells. They also modulated stress signaling by reducing p38 MAP kinase phosphorylation. NGC and SAM treatments enhanced proximal insulin signaling by decreasing serine phosphorylation of insulin receptor substrate-1 (IRS-1) and increasing its tyrosine phosphorylation. SAM and NGC treatments also modified distal insulin signaling by enhancing protein kinase B (PKB) and glycogen synthase kinase-3-beta (GSK-3 beta) phosphorylation in muscle cells. Glucose uptake was enhanced in muscle cells after treatment with SAM and NGC. We observed increased glucose tolerance, glucose-stimulated insulin secretion, decreased insulin resistance, and increased beta cell function in diabetic mice treated with NGC. The results of our study demonstrate that clove extract and its active agent NGC can be potential therapeutic agents for alleviating insulin resistance.

Optimization of hydrothermal synthesis of Fe-TiO₂ nanotubes and influence of parameters for the photodegradation of diazo dye using response surface methodology

Zulakha Zafar,Muhammad Naveed Afridi,Jong-Oh Kim 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

An Integrated Approach to Linking Job Love with Contextual Factors and Performance: An Empirical Study from Pakistan

Naila BIBI,Bilal Bin SAEED,Muhammad Asim AFRIDI 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.5

Job love is an emerging phenomenon, which is the utmost approach to fulfilling employees’ and organizations’ mutual interests, especially performance. The current study aims to define and extend the existing proposed construct of “loving one’s job” as job love. It provides a novel theoretical multi-level framework of job love, contextual factors, and performance principled on the attraction-selection-attrition framework and social exchange theory through an integrated approach. This study collected cross-sectional data through a questionnaire from 332 nurses across eight tertiary hospitals in Khyber Pakhtunkhwa, Pakistan. The findings are based on the structural equation modeling technique (SEM) at multi-levels. The results show significant relationships between job love, contextual factors, and performance at the individual and organization levels. There are some insignificant relationships between the variables at the cross-level. Job love plays a key role for both employees and organizations. It facilitates the individuals in the recruitment process to select the job they love, be a good fit, and stay committed to that particular job and organization. This phenomenon allows people to pursue their common interests. Job love assists firms in developing human resource capacity utilization plans that satisfy the needed requirements.

Application of conventional and modified cloud point extraction for simultaneous enrichment of cadmium, lead and copper in lake water and fish muscles

Muhammad Bilal,Tasneem G. Kazi,Hassan I. Afridi,Mohammad Balal Arain,Jameel A. Baig,Mustafa Khan,Naeemullah Khan 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.40 No.-

A new method based on modification of cloud point extraction for simultaneous enrichment ofcadmium, lead and copper in water and fish muscle samples was proposed. The extraction efficiency bymodified cloud point extraction (m-CPE) was compared with conventional cloud point extraction (c-CPE)method. The procedure for both CPE methods was comprised of formation of metal complexes with ahydrophobic chelating agent, dithizone, followed by entrapment of the chelates in a nonionic surfactant,Triton X-114. For c-CPE, the surfactant rich phase was treated with ethanolic solution of nitric acid andanalyzed by flame atomic absorption spectrometer (FAAS). Whereas for m-CPE, aqueous nitric acid wasused to back extract the metal ions from the surfactant rich phase and finally determined. The efficiencyof the methods was tested by analyzing certified reference material and standard addition to a realsample. All the experimental parameters were optimized. At optimized experimental conditions,preconcentration and enhancement factors were 62.5 and 78.0 to 83.0 respectively for m-CPE, 25.0 and56.0% higher than that of c-CPE. This improvement might be due to elimination of the effects ofsurfactant on the signal of analytes by FAAS. The developed method of m-CPE was applied successfullyfor analysis of the selected heavy metals in water and muscle tissues samples of fish of different lakes inSindh, Pakistan.

Application of modified cloud point extraction method for the chromium speciation in artificial saliva extracts of different snuff products

Asma Akhtar,Tasneem Gul Kazi,Hassan Imran Afridi,Mustafa Khan,Muhammad Bilal,Noman Khan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.59 No.-

A modified cloud point extraction method (m-CPE) was developed for the speciation of chromium species (Cr3+ and Cr6+) in artificial saliva extracts (ASE) of snuff products. In this method, Cr3+ was complexed with 8-hydroxyquinoline, which was trapped in nonionic surfactant (Triton X-114), prior to analyzed by electrothermal atomic absorption spectrometer (ETAAS). Whereas, the total extractable Cr was determined by reducing Cr6+ to Cr3+ using Na2SO3 as a reducing reagent. Several parameters were optimized for the developed m-CPE. Under the most favorable conditions, enrichment factor, enhancement factor and limit of detection for the proposed method were 60, 134 and 0.04 μg L−1, respectively having relative standard deviation <5%. Health risks associated with the intake of total Cr in snuff products was also assessed. Estimated daily intake of Cr via sniffing 10 g/day of dry and moist snuff products was found below the maximum tolerable daily intake whereas the calculated risk for cancer due to Cr was observed in the acceptable range of 10 E−6–E−4.