Showing papers in "Desalination and Water Treatment in 2018"

Applicability of dragon fruit (Hylocereus polyrhizus) peels as low-cost biosorbent for adsorption of methylene blue from aqueous solution: kinetics, equilibrium and thermodynamics studies.

Abstract: aFaculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia, Tel. +60355211721; emails: ahjm72@gmail.com, ali288@salam.uitm.edu.my bChemistry Department, College of Science, Al-Muthanna University, Iraq, Tel. +9647816827372; email: afafmurtadha@yahoo.com cSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia, Tel. +604 6534031; email: nyingshin@yahoo.com

Equilibrium isotherms, kinetics, and thermodynamics studies of methylene blue adsorption on pomegranate (Punica granatum) peels as a natural low-cost biosorbent

Abstract: In this work, the potential of biomass waste, pomegranate (Punica granatum) peel (PP) as low cost adsorbent for adsorption of methylene blue (MB) from aqueous solution was studied. The physicochemical properties of PP were characterized using instrumental analyses such as CHNS-O analyzer, Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and point of zero charge (pHpzc) analysis. Batch mode adsorption studies were conducted by varying operational parameters such as adsorbent dosage (0.02–0.16 g), solution pH 3–11, initial MB concentrations (50–300 mg/L), and contact time (0–390 min). The equilibrium data was found to better fit with Langmuir isotherm model compare to Freundlich model. The maximum adsorption capacity, qmax of PP for MB was 200 mg/g at 303 K. The kinetic study revealed that the present system obeyed pseudo-second-order (PSO) model. The thermodynamic adsorption parameters, standard enthalpy (ΔH°), standard entropy (ΔS°), and standard free energy (ΔG°) showed that the adsorption of MB onto PP surface exothermic and spontaneous under the experimented conditions. All results mentioned above indicate that the PP can feasibly employ for the elimination of MB from aqueous solution.

Rare earth elements removal techniques from water/wastewater: a review

Abstract: aEnvironmental and Nanoscience Research Group, University of the Western Cape, P.M.B. X17, Bellville 7535, South Africa, Tel. +27786469091; emails: pereaokola@gmail.com (O. Pereao), chrisbodealuko@gmail.com (C. Bode-Aluko), ofatoba@uwc.ac.za (O. Fatoba), lpetrik@uwc.ac.za (L. Petrik) bFederal Ministry of Education, Federal Secretarial Phase III, Abuja, Nigeria cLappeenranta University of Technology, Laboratory of Separation Technology, P.O. Box 20, 53851 Lappeenranta, Finland, email: katri.laatikainen@lut.fi

Efficient adsorption of cobalt on chemical modified activated carbon: Characterization, optimization and modeling studies

Abstract: Herein, granular activated carbon (GAC) was modified chemically with sodium dodecyl sulfate (SDS) to prepare MGAC as an efficient adsorbent for removal of Co(II) ion from aqueous solution. The effect of different SDS concentrations and modification time on the adsorption performance was examined. The as-prepared adsorbent was characterized by FESEM and FT-IR techniques. Moreover, some parameters affecting the adsorption efficiency like solution pH, contact time, adsorbent dosages, initial metal ion concentrations, temperature and agitation speed on the adsorption efficiency were evaluated in a batch environment. Under same operational conditions, MGAC showed a much greater adsorption rate than GAC, due to synergistic effect between GAC and SDS. The equilibrium time was 90 min and the maximum adsorption capacity based on the Langmuir was found to be 51 mg/g. Experimental data were in good agreement with Langmuir and pseudo-second-order models. The mechanism of Co ion adsorption on MGAC followed ion-exchange and mono layer chemical adsorption. The adsorption process showed better performance at neutral pH and higher temperatures. Under optimized conditions, complete removal of 20 mg/L of Co(II) was obtained in the presence of 1.2 g/L of MGAC. Thermodynamic studies indicated the adsorption process was endothermic and spontaneous in nature. © 2018 Desalination Publications. All rights reserved.

Two-dimensional zeolitic imidazolate framework-8 for efficient removal of phosphate from water, process modeling, optimization, kinetic, and isotherm studies

Abstract: aDepartment of Environmental Health Engineering, Neyshabur University of Medical Sciences, Neyshabur, Iran, email: mohammadi.eng73@gmail.com (A.A. Mohammadi) bEnvironmental Health Engineering, School of Health, Gonabad University of Medical Sciences, Gonabad, Iran, emails: a.zarei.tums@gmail.com (A. Zarei), mafsharnia2000@yahoo.com (M. Afsharnia) cSocial Determinants of Health research center, Mashhad University of Medical Sciences, Mashhad, Iran, emails: shamsmh@mums.ac.ir (M. Shams), alidadih@mums.ac.ir (H. Alidadi) dDepartment of Environmental Health Engineering, School of Health, Mashhad University of Medical Sciences, Mashhad, Iran

Carbonization of corn (Zea mays) cob agricultural residue by one-step activation with sulfuric acid for methylene blue adsorption

Abstract: aFaculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia, Tel. +603 55211721; emails: ahjm72@gmail.com, ali288@salam.uitm.edu.my (A.H. Jawad), Tel. +603 55436594; email: mohdsufrimastuli@yahoo.com (M.S. Mastuli) bDepartment of Chemistry, College of Science, Al-Muthanna University, Iraq, Tel. +9647809400813; email: Samohammed15@gmail.com cFaculty of Applied Sciences, Universiti Teknologi MARA, 02600 Arau, Perlis, Malaysia, Tel. +60 49882737; email: mohdfauziabd@perlis.uitm.edu.my

Investigation of the efficiency of heterogeneous Fenton-like process using modified magnetic nanoparticles with sodium alginate in removing Bisphenol A from aquatic environments: kinetic studies.

Abstract: Bisphenol A (BPA) is one of the endocrine disrupting compounds that has significant estrogenic effects and if it is not treated, it will enter into water resources and will cause irreparable environmental problems. Thus, this study aims at determining the efficiency of heterogeneous Fenton-like process using modified magnetic nanoparticles with sodium alginate in removing BPA from aquatic environments. In this experimental research, the effects of environmental factors including pH (3–9), contact time (10–180 min), initial concentration of catalyst (0.5–20 g/L), initial concentration of hydrogen peroxide (50–300 mg/L) and the initial concentration of BPA (10–60 mg/L) were studied in removing efficiency of BPA using processes of heterogeneous Fenton-like, alginate sodium and hydrogen peroxide. Results of present study showed that during heterogeneous Fenton-like process, the highest removal efficiency (BPA) is achieved (95) at pH 5, catalyst concentration 5 g/L, initial concentration of hydrogen peroxide 100 ppm and BPA concentration 20 ppm in 120 min in a way that the processes of sodium alginate and hydrogen peroxide had smaller removal efficiency. Also, studies of kinetic reaction revealed that removal of BPA in heterogeneous Fenton-like process followed a second-order kinetic model (R2 = 0.98). Results demonstrated that heterogeneous Fenton-like process is able to remove BPA effectively from aquatic environments using modified magnetic nanoparticles with sodium alginate as a catalyst under optimal conditions and this process could be used to remove other similar compounds. © 2018 Desalination Publications. All rights reserved.

Comparative evaluation of nitrate adsorption from aqueous solutions using green and red local montmorillonite adsorbents.

Abstract: Nitrate has been identified as a major pollutant in water resources. In this study, two new adsorbents, namely, red local montmorillonite (RLM) and green local montmorillonite (GLM) were used as adsorbents, and their characteristics and performance in nitrate adsorption has been investigated. The most important factors in the adsorption process such as initial pH, adsorbent dosage, contact time and initial concentration of nitrate were investigated. Also, EDAX, BET, SEM and FTIR techniques were used to determine adsorbent characteristics. The results showed that the highest nitrate adsorption for both adsorbents obtained at low pH values, and removal efficiency increased by increasing the dosage and contact time and decreased by increasing the initial concentration of nitrate. EDAX technique showed that the amount of MgO in GLM and RLM were 2.6 and 1.4 respectively, indicating a double amount of MgO in GLM structure. MgO can have a very important role in nitrate adsorption but BET technique showed that the specific surface area of RLM is more than GLM. Overall results showed that the adsorption capacities of GLM and RLM were relatively high and the values were 89.2 and 87.7 mg/g, respectively. High adsorption capacity can nominate two new adsorbents for nitrate adsorption. Adsorption process followed the Langmuir isotherm and the experimental data followed the pseudo second-order kinetic. Also, the results of thermodynamic experiments showed that the adsorbing reaction for both adsorbents was exothermic and they occurred spontaneously.

Sewage information monitoring system based on wireless sensor

Abstract: In order to carry out real-time monitoring of water quality, this paper developed a set of remote realtime water quality monitoring system based on ZigBee protocol wireless sensor network technology, and chose Qingshan Lake in Nanchang as the experimental field of water quality monitoring system. In addition, running and testing are conducted for the water quality monitoring system for a period of time. The results show that the designed system achieves effective water quality and real-time monitoring, wireless data transmission monitoring, storage and display of software platform for data, and remote control of monitoring equipment. What’s more, on-site testing and inspection of related functions are carried out, which can work stably in the harsh environment. It is concluded that real-time collection of water quality monitoring data and transmission through the wireless network to the monitoring center achieve the goals of research.

Comparative study on seasonal variation in hydro-chemical parameters of Ganga River water using comprehensive pollution index (CPI) at Rishikesh (Uttarakhand) India

Abstract: The assessment of the Ganga River System at Rishikesh was investigated at five different sites for three different seasons (summer, winter and monsoon) using comprehensive pollution index (CPI), considering 10 physicochemical parameters such as conductivity, turbidity, total dissolved solids, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, total hardness, Cl, phosphate and sulphate. The CPI was found to be 0.54–2.47, which indicates the variation in pollution level of the River Ganga. The variation in pollution index value clearly shows that water quality was slightly polluted in winter (0.54–0.72) and summer (0.64–0.88) whereas high contamination (1.68–2.47) was observed during monsoon season. Among various sampling stations, Pashulok Barrage (Site 5) was more contaminated than other sites. All the studied parameters were under the permissible limit of W.H.O. (2011) except turbidity, total solids and suspended solids which were higher than the permissible limit. This study also illustrates the correlation between parameters by developing correlation matrix. The result of this study clearly elucidates that the water quality is getting contaminated as we moved from upstream to downstream of river and helps to understand the potential effects of water quality on drinking, irrigation and other purposes.

Large surface area activated carbon from low-rank coal via microwave-assisted KOH activation for methylene blue adsorption

Abstract: Merit Kapit (MK) as a low-rank Malaysian coal was utilized as a precursor to develop a large surface area activated carbon (MKAC) via a microwave-induced KOH activation. The characterizations of the raw MK and MKAC were investigated by surface area analysis, scanning electron microscopy, X-ray diffraction, Fourier transform infrared, elemental analysis (CHNS) and point of zero charge (pHPZC) method. The surface area of MKAC was remarkably increased up to 1,100.18 m2/g compared with 332.61 m2/g of MK before activating process. The adsorptive properties of the MKAC with methylene blue (MB) was conducted at different adsorbent dose (0.3–3.6 g/L), solution pH (2–12), initial dye concentrations (25–350 mg/L), contact time (0–240 min) using batch mode operation. The impregnation ratio is 1:2 (MK:KOH), microwave power of 600 W, and radiation time of 15 min resulted in MKAC with a monolayer adsorption capacity of 200 mg/g for MB at 30°C and carbon yield of 63.6%. The kinetic profiles were described by the pseudo-second-order kinetics. Thermodynamic functions indicate a spontaneous and endothermic nature of the adsorption. This study introduces MK as a promising renewable precursor for developing a large surface area activated carbon.

Heat carrier nanofluids in solar still - A review

Abstract: This review discusses heat transfer enhancement of various nanoparticles in solar stills. The thermal conductivities of various nanoparticles, that is, Al2O3, CuO, Cu2O, ZnO, SnO2, TiO2, SiO2, Cu, Fe2O3, SiC, and multiwalled carbon nanotubes suspended in water with different volume fractions are analyzed. The factors involved in the thermal conductivity and distillation enhancement of nanofluids are discussed. This review is crucial because thermal conductivity enhancement augments the fresh water yield.

Possible utilization of PET waste as adsorbent for Orange G dye removal from aqueous media.

Abstract: aDepartment of Environmental Engineering and Management, Faculty of Chemical Engineering and Environmental Protection “Cristofor Simionescu”, “Gheorghe Asachi” Technical University of Iaşi, 73 Prof. Dimitrie Mangeron Street, 700050 Iaşi, Romania, Tel./Fax: + 40 232 271759; emails: lbulg@ch.tuiasi.ro (L. Bulgariu) bianka_eco@yahoo.com (B. Cojocariu); grusu@ch.tuiasi.ro (G. Nacu) bGreenFiber International Company, Calea Chisinaului, 29, 700177 – Iaşi, Romania cDepartment of Organic, Biochemical and Food Engineering, Faculty of Chemical Engineering and Environmental Protection “Cristofor Simionescu”, “Gheorghe Asachi” Technical University of Iaşi, 73 Prof. Dimitrie Mangeron Street, 700050 Iaşi, Romania, email: ancamocanu@ch.tuiasi.ro