Min Of Contact Time Research Articles

Adsorption of BTX from produced water by using ultrasound-assisted combined multi-template imprinted polymer (MIPs); factorial design, isothermal kinetics, and Monte Carlo simulation studies

Benzene, toluene, and xylene (BTX) were considered severe types of volatile organic compounds (VOCs) that adversely affect the environment. Therefore, this research directed to BTX removal using a combination technique between molecular imprinted polymer (MIP) and ultrasound (US) to achieve high BTX removal efficiency. MIP was synthesized, characterized, and followed by an optimization process for the different conditions to obtain the optimum factors that achieve high BTX removal efficiency. Isothermal and kinetic modeling was established to identify the adsorption nature of the BTX removal process. Results stated that MIP/US was the best treatment that furtherly optimized to achieve 98.3 %, 98.5 %, and 99 % BTX removal efficiency for 100 ppm concentration of BTX, after a 10-minute contact time. Furthermore, the optimization process stated that by using 500 ppm BTX concentration, 2 g/l MIP dose, after 10 min contact time, Benzene removal was 91.517 %, Toluene removal was 95.517 %, and Xylene achieved 77.84 % removal at 50-ultrasound power. Freundlich isotherm and pseudo-second-order reaction were formfitting well with the BTX removal process. Monte Carlo and adsorption simulation conducted through Material studio gateway, and the simulation outputs confirm that MIPs is a good candidate for BTX removal with higher adsorption efficiency.

Effect of poly-aniline coated iron ore mining waste (PANI@IOMW) as efficient adsorbent on mitigation of Cr (VI) from aqueous solution: Experimental and statistical investigation

Present investigation is focused on the synthesis of poly-aniline coated iron ore mining waste (PANI@IOMW) adsorbent and its utilization for remediation of Cr (VI) from water using batch process. The studied adsorbent shows excellent Cr (VI) mitigation properties with highest efficiency of 99% at significantly low dosage of 0.15 g, pH 2.0, 90 min contact time and 50 mgL−1initial concentrations. Non-linear regression analysis shows that Freundlich isotherm is considers as a suitable model for mitigation of Cr (VI) with Qmax of 73.29 mg/g for 50 mgL−1 Cr (VI) concentration. Pseudo second order kinetics model is considered as a best fitted model for the present investigation. Thermodynamic study shows that adsorption is spontaneous and endothermic in nature. The value of mean free energy (0.983 J/mol at 303 K) and activation energy (7.96 kJmol−1 at 303 K) shows that adsorption of Cr (VI) on PANI@IOMW occurs through physisorption. Surface study of PANI@IOMW was done using FESEM, EDX, FTIR, XRD, XRF, XPS, HR-TEM and AFM analysis. The comparison of % efficiency of Cr (VI) removal obtained by response surface methodology (RSM) (99.06%) and experimental studies under the optimum conditions (99%) suggested that quadratic model is suitable model for Cr (VI) adsorption. The adsorbent PANI@IOMW shows regeneration ability up to two cycles without losing its properties. Thus PANI@IOMW adsorbent can be used for treatment of water containing Cr (VI) as good alternative as compared to chemical adsorbents used by the industries.

ZEOLITIZATION OF COAL WASTE AS Cu(II) ION ADSORBENT

TZeolization of coal waste was carried out as an adsorbent for Cu(II) ions. Fly ash tailings were collected from Lati Steam Power Plant (SPP) Berau and tested using SEM instruments, X-ray diffraction and AAS. Synthetic zeolites are prepared by hydrothermal reaction under alkaline and alkaline conditions. Characterization of the synthetic zeolite using SEM has formed a zeolite material with a pore size >10 µm and shows an increase in the amount of Na from 3.06% to 11.82%. XRD results show that Na-P1 zeolite is formed at the main top of 2θ16, 30, 33, 10 and 40, 80, and the relative intensities are 34, 31 and 36, respectively. In addition, elemental materials such as silica and mullite are continuously formed on the main top of 2θ26.50 and 26.10, the relative strength of silica is 100, and the relative strength of mullite is 57.9. The optimum adsorption capacity of zeolite for maximum copper ion was 80.330% at pH=4, 97.958% at 150 mg adsorbent weight, and 94.550% at 50 min contact time. The formation of these new materials significantly improved the adsorption capacity of fly ash under optimal conditions of pH = 4, sorbent weight of 150 mg, and contact time of 50 min.

Electrosorption of phenolic compounds by carbon sheet electrode from zinc chloride functionalized activated carbon from pomegranate husk

The biomass waste from pomegranate husk (PH) was utilized to develop carbon sheet electrode via the chemical and thermal activation approach and the electrode was used to remove 4-chlorophenol (4CP) from the aqueous solution. The effect of solution pH, ionic strength, applied voltage, contact time, and 4CP concentration were investigated to observe the highest 4CP removal efficiency of the biomass derived material at pH 6.0, applied voltage of 1.5 V, ionic strength of 0.85 mM, and contact time of 270 min. The increased applied voltage led to 4CP removal efficiency up to 95.38 ± 4.77 % at 1.5 V with 60 min contact time, nearly-two-times higher than that observed at the open circuit (62.33 ± 3.12 %). The removal efficiency of 4CP sharply decreased from 96.63 ± 1.93 % to 49.34 ± 1.48 % with increasing initial 4CP concentration (50.0–200.0 mg/L). Experimental data were fitted to Freundlich isotherm according to which high sorption capacity of carbon electrode equivalent to 325.85 mg/g at 1.5 V of the applied voltage was observed. The fabricated carbon electrode offered a great potential for the removal of other phenolics from the possible biomass via sorption approach.

Efficient Removal of Phosphate from Wastewater by a Novel Phyto-Graphene Composite Derived from Palm Byproducts.

The increased demand for clean water especially in overpopulated countries is of great concern; thus, the development of eco-friendly and cost-effective techniques and materials that can remediate polluted water for possible reuse in agricultural purposes can offer a life-saving solution to improve human welfare, especially in view of climate change impacts. In the current study, the agricultural byproducts of palm trees have been used for the first time as a carbon source to produce graphene functionalized with ferrocene in a composite form to enhance its water treatment potential. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy, X-ray diffraction (XRD), ultraviolet-visible, Fourier transform infrared spectroscopy, zeta potential, thermogravimetric analysis, and Raman techniques have been used to characterize the produced materials. SEM investigations confirmed the formation of multiple sheets of the graphene composite. Data collected from the zeta potential revealed that graphene was supported with a negative surface charge that maintains its stability while XRD elucidated that graphene characteristic peaks were evident at 2θ = 22.4 and 22.08° using palm leaves and fibers, respectively. Batch adsorption experiments were conducted to find out the most suitable conditions to remove PO4 3- from wastewater by applying different parameters, including pH, adsorbent dose, initial concentration, and time. Their effect on the adsorption process was also investigated. Results demonstrated that the best adsorption capacity was 58.93 mg/g (removal percentage: 78.57%) using graphene derived from palm fibers at 15 mg L-1 initial concentration, pH = 3, dose = 10 mg, and 60 min contact time. Both linear and non-linear forms of kinetic and isotherm models were investigated. The adsorption process obeyed the pseudo-second-order kinetic model and was well fitted to the Langmuir isotherm.

Recovery of phosphate from municipal wastewater as calcium phosphate and its subsequent application for the treatment of acid mine drainage

Here, the co-managment of municipal wastewater (MWW) and acid mine drainage (AMD) is proposed, where the recovered low-value phosphorus from MWW is used for the treatment of AMD. Specifically, MWW was treated using calcium hydroxide (Ca(OH)2), a low-cost and readily available material, with the ammonia content being greatly reduced (89%) through stripping and phosphates practically eliminated (>99%). The recovered low-value phosphorus material, in the form of calcium phosphate (Ca3(PO4)2), was then used for the treatment of AMD from coal mining. Metals contained in AMD scavenged phosphorous, forming new minerals, and the increased alkalinity led to their precipitation. The optimum treatment conditions were 90 min contact time, 10 g L−1 Ca3(PO4)2 dosage, and room temperature and ambient pH. Under these conditions, AMD's metal content (Fe, Mn, Cr, Cu, Ni, Pb, Al, and Zn) was practically depleted (>99% removal) and sulphate (SO₄) greatly reduced (90.6%). Results were underpinned by FTIR, FIB/SEM, EDS/SEM, XRF, and XRD. Overall, this indirect co-treatment method holds great promise for the sustainable management of both wastewater matrices and can provide a simple and effective solution for their co-management, particularly in the developing world context where it could also help in advancing the UN's sustainable development goals.

Preparation and characterization of low-cost activated carbon from Moringa oleifera chemically activated using ZnCl2 for the adsorption of bisphenol A

The use of agricultural by-products such as Moringa oleifera plants is one effort to support the reduction of environmental pollution. Activated carbon produces from agricultural wastes is relatively less expensive and can replace traditional methods such as renewable as well as nonrenewable materials such as petroleum residue and coal. In this study, the removal of bisphenol A from aqueous media was studied using activated carbon produced from M. oleifera pods and peels. A batch adsorption study was carried out by varying the parameters of the adsorption process. A maximum removal percentage of 95.46% was achieved at optimum conditions of 2.5 g L−1 adsorbent dose, pH 7, 60 min contact time and 20 mg L−1 initial concentration of BPA. The BET surface areas of MOP, MOP-AC and MOP-ACZ were found to be 12.60, 4.10 and 45.96 m2/g, respectively. The experimental data were analyzed by Langmuir, Freundlich and Temkin adsorption isotherm models. Equilibrium data fitted well with the Langmuir isotherm with a maximum monolayer adsorption capacity of 20.14 mg g−1. The rates of adsorption were found to conform to the pseudo-second-order kinetics with a good correlation. The results indicate that the M. oleifera activated carbon could be employed as a low-cost alternative to commercial activated carbon in the removal of BPA from water.

Removal of asphaltene by solid‐phase iron exchanged bentonite

AbstractThe purpose of this study was to modify bentonite (B) by iron using the solid‐phase ion exchange method to enhance the asphaltene adsorption. According to the scanning electron microscope (SEM) and x‐ray diffraction analysis (XRD) results, after solid‐state ion exchange, the structure of parent bentonite was changed slightly. An energy‐dispersive x‐ray analysis (EDX) showed that after ion exchange, the iron contents of bentonite increased from 0.6% to 1.6% w/w. Bentonite modification with iron increases asphaltene adsorption capacity (about 60%) compared to parent bentonite. Optimal adsorbent conditions for adsorption of asphaltene are 100 ppm concentration, 5 g/L adsorbent, and 60 min contact time. Adsorbent behavior showed that the adsorption kinetics and isotherm are in good agreement with the pseudo‐second‐order model and the Langmuir equation.

Transparent Anti-SARS COV-2 Film from Copper(I) Oxide Incorporated in Zeolite Nanoparticles

The high antibacterial and antiviral performance of synthesized copper(I) oxide (Cu2O) incorporated in zeolite nanoparticles (Cu-Z) was determined. Various Cu contents (1-9 wt %) in solutions were loaded in the zeolite matrix under neutral conditions at room temperature. All synthesized Cu-Z nanoparticles showed high selectivity of the cuprous oxide, as confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. An advantage of the prepared Cu-Z over the pristine Cu2O nanoparticles was its high thermal stability. The 7 and 9 wt % Cu contents (07Cu-Z and 09Cu-Z) exhibited the best activities to deactivate Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. The film coated with 07Cu-Z nanoparticles also had high antiviral activities against porcine coronavirus (porcine epidemic diarrhea virus, PEDV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Specifically, the 07Cu-Z-coated film could reduce 99.93% of PEDV and 99.94% of SARS-CoV-2 viruses in 5 min of contact time, which were higher efficacies and faster than those of any previously reported works. The anti-SARS-CoV-2 virus film was coated on a low-cost PET or PVC film. A very small amount of cuprous oxide in zeolite was used to fabricate the antivirus film; therefore, the film was more transparent (79.4% transparency) than the cuprous oxide film or other commercial products. The toxicity of 07Cu-Z nanoparticles was determined by a toxicity test on zebrafish embryo and a skin irritation test to reconstruct a human epidermis (RhE) model. It was found that the impact on the aquatic environment and human skin was lower than that of the pristine Cu2O.

Green biosynthesis of Fe3O4 nanoparticles using Chlorella vulgaris extract for enhancing degradation of 2,4 dinitrophenol

ObjectivesThis study aimed to provide the excellent role of Chlorella vulgaris extract as a green, reducing agent for improving and enhancing the effectiveness and performance of as-prepared NPs, which is higher than bare Fe3O4. MethodsThe extract of the algal cell of Chlorella vulgaris is used as a green, reducing agent was used to prepare green Fe3O4 NPs to improve and enhance the degradation effectiveness of 2,4 dinitrophenol (2,4 DNP) in their aqueous solution using UV irradiation. The as-synthesized bare Fe3O4 and green Fe3O4 NPs were characterized using UV–VIS spectroscopy, TEM, SEM, EDX, XRD, and FT-IR spectroscopy to determine bandgap energy, particle size, structural morphology, crystallite nature, phase structure, elemental compositions, and existed functional group. ResultsSEM and TEM images indicated that the as-synthesized NPs have a regular spherical shape with a mean size ranging between 13.68 and 31.71 nm. The energy bandgap (Eg) indicated the green Fe3O4 NPs have low values (2.73 and 2.3 eV) than bare Fe3O4 (2.89 eV). The maximum degradation of 2,4 DNP was achieved at pH = 8, 90 min contact time, 0.35 g/L catalyst dose, and 100 mg/L 2,4 DNP concentration. ConclusionThe degradation results proved that green Fe3O4 NPs have more effectiveness than bare Fe3O4 NPs.

Comparative adsorptive performance of adsorbents developed from kaolin clay and limestone for de-fluoridation of groundwater

Excessive fluoride in potable groundwater is a serious health problem in rural areas of many developing countries. This research was designed to assess the efficiency of low-cost adsorbents for the removal of fluoride ions by using natural kaolin clay and limestone. The kaolin clay and limestone were first, subject to a beneficiated process to remove impurities. Then the thermal process was conducted at 750 °C for adsorbent preparation. The crystalline structure of thermally treated and raw materials was analyzed using X-ray diffraction (XRD). The functional groups before and after fluoride adsorption were determined by Fourier transform infrared spectroscopy (FTIR). The chemical composition and thermal stability of the adsorbent material were also investigated using atomic absorption spectroscopy (AAS), and differential thermal analysis (DTA) respectively. The prepared adsorbent materials were subjected to batch adsorption studies with different adsorption parameters including contact time, pH, adsorbent dosage, and temperature. The optimal fluoride removals in both adsorbents were obtained at a temperature of 60 °C, pH 5, a dose of 0.6 g, and at 60 min contact time. The optimum fluoride adsorption capacity was found 3.58 mg/g and 1.85 mg /g for kaolin clay and limestone, respectively. The adsorption process follows Freundlich isotherm models and Pseudo-Second-order kinetic model. The interaction effects with a 3D plot of operating parameters on the defluoridation capacity were analyzed using a design expert and confirmed that there were significant effects on fluoride adsorption. It can be concluded that kaolin and limestone showed the best results in terms of cost-effectiveness, adsorption efficiency and reusability for fluoride ion adsorption.

Facile synthesis of Tri-metallic layered double hydroxides (NiZnAl-LDHs): Adsorption of Rhodamine-B and methyl orange from water

In this research work, tri-metallic layered double hydroxides (NiZnAl-LDH) nano-sheets were efficiently synthesized by hydrothermal technique and applied for the decontamination of rhodamine B (Rh-B) and methyl orange (MO). Material characterizations confirm the formation of tri-metallic NiZnAl-LDH nano-sheets of continuous macrostructure skeleton with interconnected macropores. Several adsorption factors like initial concentration, pH of dyes solution, contact time and adsorbent dosage were investigated. Results exposed that synthesized NiZnAl-LDH perform best in basic medium for the removal of Rh-B and in mild acidic for that of MO. Also with 210 min contact time NiZnAl-LDH showed adsorption efficiency of 38.03 mg/g for Rh-B and 32.67 mg/g for that of MO. The Langmuir model perfectly defined the adsorption process on to the surface of NiZnAl-LDH as monolayer with relatively higher R2 value (R2 = 0.978 for Rh-B and 0.996 for MO). The maximum adsorption capacities (qmax) calculated with Langmuir model were 97.09 mg/g for Rh-B and 105.26 mg/g for MO, which are analogous with other conventional adsorbents. Furthermore, the adsorption of Rh-B and MO onto NiZnAl-LDH follow pseudo second order kinetics indicating that adsorption process is independent to that of concentration of adsorbate. Additionally, reusability experiment confirmed that the fabricated tri-metallic LDHs nano-sheets own outstanding recyclability with qe = 21.25 mg/g of Rh-B and 28.55 mg/g of MO at 4th regeneration cycle. The outcomes of this research could serve as a foundation for designing and engineering exceptional materials for purification of industrial waste water.

Hagenia abyssinica leaf powder as a novel low-cost adsorbent for removal of methyl violet from aqueous solution: Optimization, isotherms, kinetics, and thermodynamic studies

Dye effluents generated by industries have a significant impact on water quality. Unfortunately, traditional wastewater treatment techniques are incapable of dye removal from polluted water at the required levels. Nowadays, wastewater treatment needs the development of eco-friendly and profitable pollutant adsorbents. In this study, Hagenia abyssinica leaf powder (HALP) adsorbent was used to eliminate methyl violet dye (MVD) from aqueous solution. HALP adsorbents before and after MVD adsorption were analyzed using scanning electron microscopy (SEM) and a Fourier transform infrared (FT-IR) spectrometer. Batch adsorption experiments were conducted to examine the effects of initial concentration, adsorbent dose, contact time, and solution pH on MVD adsorption using HALP. As a result, 0.2 g adsorbent dose, 100 mg/L MVD solution, 50 min contact time, and a solution pH of 6 were determined as the optimum adsorption process conditions. Adsorption isotherms were used to test the experimental data and the result is well-fitted to the Langmuir model with a maximum adsorption capacity of 68.96 mg/g. Adsorption kinetics were studied using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, and the experimental data is well-fitted with the pseudo-second-order model. The thermodynamic data Δ H ∘ (9.564 kJ/mol), Δ G ∘ (-2824.744 to -1693.976 J/ mol) and Δ S ∘ (37.373 J/(mol.K)) indicated that the adsorption process is endothermic, spontaneous, and rise randomness at HALP/solution interface, respectively. The current work confirmed that HALP is one of the most effective, eco-friendly, and sustainable dye adsorbents from solutions compared to those derived from a household, agricultural, and industrial waste. • Hagenia abyssinica leaf powder (HALP) was employed to remove methyl violet dye (MVD). • HALP adsorbent before and after MVD adsorption were analyzed. • After dye adsorption, the surface structure and absorption peak position changed. • The adsorption process depends on initial concentration, dose of HALP, time of contact, and pH. • HALP can successfully remove MVD molecules from aqueous solutions.

Solvent Extraction Studies of Copper from a Heap Leach Liquor Using Mextral 5640H

In this study the extractive capability of Mextral 5640H was investigated for extraction of copper from a heap leach liquor. In this regard, the influence of parameters such as pH (0.2–2.8), extractant concentration in kerosene diluent (2.5%–10% v/v), temperature (25–70 °C), contact time (0–300 s), stirring speed (100–1200 rpm), phase ratio (O/A) (0.6–1.8) and Cu initial concentration (0.5–2 g/L) in the leach liquor were examined and optimized. The findings demonstrated that the Mextral 5640H extractant had a very high efficiency and selectivity in copper extraction from the leachate. 98.17% Cu, with less than 0.5% of Fe and Mn, were extracted at pH 1.6, 10% (v/v) Mextral 5640H concentration, ambient temperature (25 °C), 400 rpm stirring speed, 2 min contact time and an O/A phase ratio of 1:1. Under equilibrium conditions it was found that one mol of Cu is extracted by 7 mol of Mextral 5640H. Additionally, analysis using a McCabe–Thiele diagram suggests a two-stage extraction to reach the maximum extraction of copper (99.5%) from the leachate at operational condition using industrial mixer-settlers. Furthermore, a thermodynamic study was conducted, and the measured values of ΔH = 15.13 kJ/mol, ΔG = −6.95 kJ/mol and ΔS = 74.10 J/mol/K indicate an endothermic, spontaneous nature and high affinity of copper extraction.

Clay-Alginate Beads Loaded with Ionic Liquids: Potential Adsorbents for the Efficient Extraction of Oil from Produced Water

Produced water (PW) generated from the petroleum industry, during the extraction of oil and gas, has harmful impacts on human health and aquatic life, due to its complex nature. Therefore, it is necessary to treat it before discharging it into the environment in order to avoid serious environmental concerns. In this research, oil adsorption from PW was investigated using clay-alginate beads loaded with ionic liquids (ILs), as the adsorbent material. The effects of several process parameters, such as the initial concentration of oil, contact time, pH, and temperature on the removal efficiency of the beads, were analyzed and optimized. Different characterization methods, such as the Fourier transform infrared spectrophotometer (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and thermal gravimetric analysis (TGA), were used to investigate the surface morphology, the chemical bond structure and functional group, and the thermal stability of the ILs-based beads. The results revealed that the clay-alginate-ILs beads indicated a removal efficiency of 71.8% at the optimum conditions (600 ppm initial oil concentration, 70 min contact time, 10 pH, and at room temperature) with an adsorption capacity of 431 mg/g. The FTIR analysis confirmed the successful chemical bond interaction of the oil with the beads. The SEM analysis verified that the beads have a porous and rough surface, which is appropriate for the adsorption of oil onto the bead’s surface. The TGA analysis provides the thermal degradation profile for the clay-alginate-ILs. The beads used in the adsorption process were regenerated and used for up to four cycles.

The Effectiveness of Pahae Natural Zeolite-Cocoa Shell Activated Charcoal Nanofilter as a Water Adsorber in Bioethanol Purification.

Pahae natural zeolite potentially can be used as a filtration material because of its high adsorption capacity. However, it is known that other supportive materials such as activated charcoal are needed to optimize the utilization of natural zeolite as an adsorber. This study aims to investigate the potential use of activated charcoal which was synthesized from cocoa shells waste and natural zeolite in nanosize as the adsorber in order to increase the concentration of bioethanol. The mixing process of nanozeolite and activated charcoal of cocoa shells was carried out through mechanical mixing, while the nanofilter was made using a press-printing technique followed by sintering at several temperature variations. The results showed that the activated zeolite produced in this study has a particle size of 118.4 nm with water absorption capacity of 52.08%. In line with that, the bioethanol concentration was increased up to 78.92% during the adsorption with a 45 min contact time with water vapor. Thus, based on the results, it can be concluded that nanosized zeolite-based adsorbents and activated charcoal produced from cocoa shells can be utilized as adsorbers to significantly increase the concentration of bioethanol generated.

Virucidal PVP-Copper Salt Composites against Coronavirus Produced by Electrospinning and Electrospraying.

Electrospinning technology was used to produced polyvinylpyrrolidone (PVP)-copper salt composites with structural differences, and their virucidal activity against coronavirus was investigated. The solutions were prepared with 20, 13.3, 10, and 6.6% w/v PVP containing 3, 1.0, 0.6, and 0.2% w/v Cu (II), respectively. The rheological properties and electrical conductivity contributing to the formation of the morphologies of the composite materials were observed by scanning electron microscopy (SEM). SEM images revealed the formation of electrospun PVP-copper salt ultrafine composite fibers (0.80 ± 0.35 µm) and electrosprayed PVP-copper salt composite microparticles (1.50 ± 0.70 µm). Energy-dispersive X-ray spectroscopy (EDS) evidenced the incorporation of copper into the produced composite materials. IR spectra confirmed the chemical composition and showed an interaction of Cu (II) ions with oxygen in the PVP resonant ring. Virucidal composite fibers inactivated 99.999% of coronavirus within 5 min of contact time, with moderate cytotoxicity to L929 cells, whereas the virucidal composite microparticles presented with a virucidal efficiency of 99.999% within 1440 min of exposure, with low cytotoxicity to L929 cells (mouse fibroblast). This produced virucidal composite materials have the potential to be applied in respirators, personal protective equipment, self-cleaning surfaces, and to fabric coat personal protective equipment against SARS-CoV-2, viral outbreaks, or pandemics.

Selective removal of Cd(II), As(III), Pb(II) and Cr(III) ions from water resources using novel 2-anthracene ammonium-based magnetic ionic liquids

Facile synthesis of two 2-anthracene ammonium-based magnetic ionic liquids (MILs), 2-anthracene ammonium tetrachloroferrate (III) ([2A-A]FeCl 4 ) and 2-anthracene ammonium trichlorocobaltate (II) ([2A-A]CoCl 3 ) was performed by protonation of 2-aminoanthracene, followed complexation with FeCl 3 /CoCl 2 . The MILs were tested in the adsorptive removal of Cd 2+ , As 3+ , Pb 2+ and Cr 3+ from water sources. Upon treatment with 10 mg dosage of MILs in 10 mL aqueous solution of 50 ppm each of Cd 2+ , As 3+ , Pb 2+ and Cr 3+ , adsorption capacity (mg/g) in the range of 5.73–55.5 and 23.6–56.8 for [2A-A]FeCl 4 and [2A-A]CoCl 3 respectively were recorded. Thus, the optimization, kinetic and isotherms studies were conducted using the [2A-A]CoCl 3 adsorbent. The [2A-A]CoCl 3 was more effective in pH 7–9, and equilibrium adsorption was achieved after 60 min contact time. The adsorption process proceeded via the Pseudo-second order pathway and the Langmuir isotherm model is the best fit for the adsorption process (with q max = 227 – 357 mg/g) of all the targeted metal ions. The [2A-A]CoCl 3 adsorbent demonstrated practicality with large distribution and selectivity coefficients of the targeted ions, and up to six times regeneration.

Stability and performance studies of emulsion liquid membrane on pesticides removal using mixture of Fe3O4Â nanoparticles and span80

• Study the effect of Span 80 and Fe3O4on the stability of emulsion liquid membrane. • Investigate the effect of different parameters on the stability and extraction efficiency. • 99% of Abamectin extracted and 0.52% breakage percent achieved at the best conditions. • The extraction kinetic and mass transfer coefficient were accomplished. The current study investigated the impact of nonionic surfactant span 80 in the existence of Fe 3 O 4 magnetic nanoparticles on the emulsification of mixture of kerosene as petroleum based organic solvents and corn oil as a green diluent in the ratio 1:1, HCl was used as internal phase and the stability of the emulsion was carried out. The proposed Pickering emulsion liquid membrane has been exploited to investigate it is ability in the extraction of Abamectin pesticides from aqueous solution without utilizing carrier agent. Further, the effects of experimental parameters on extraction efficiency and emulsion stability such as, homogenizer speed, emulsification speed, contact time, Fe 3 O 4 -Span 80 ratios, HCL concentration, internal to membrane volume ratio (I/O) and pH of the external feed solution were carried out. The results showed that more than 99% of Abamectin could be extracted at 10 min contact time with a minimum breakage percent of 0.52% at the optimal conditions. The kinetic of the extraction were studied and the mass transfer coefficient was found to be for external phase ( K M ) of 1.2 × 10 − 7 , interfacial reaction rate constant ( K F ) of 5.83 × 10 − 8 and the overall mass transfer coefficient ( K O ) of 3.91 × 10 − 8 . The results of recyclability of the PELM revealed that the emulsion stability and extraction efficiency was nearly unchanged after three cycles.

Long-lasting renewable antibacterial graphene/N-halamine-coated cotton fabrics benefitting from enhanced UV stability and quantitative tracking of bactericidal factors

In this study, anionic GO aqueous dispersion and cationic QAS aqueous solution with specific concentrations were applied for the fabrication of modified cotton fabrics (MCFs) through the layer-by-layer self-assembly method. The chlorinated cotton fabrics with optimized protocol possessed excellent ultraviolet-blocking properties, with a UPF value of 323.08. Moreover, graphene greatly improved the UV stability of N-halamine, which could also be proved in the UV aging test of MCFs. In addition, the modification procedure also endowed cotton fabrics with superhydrophobic properties, thus broadening the application range of cotton fabric. The obtained GQC10 possessed excellent antibacterial activity, with all inoculated S. aureus and E. coli O157:H7 being completely killed within 5 min and 1 min of contact time, respectively. Indicated by the quantitative function relation between the active chlorine content (ACC) and the surface sheet resistance (SSR) of the MCFs, a novel and simple method for the determination of ACC was established. This method could be used to monitor the antimicrobial efficacy to ensure its sustainability. Furthermore, according to the variation frequency of SSR, the risk level of bacterial hazards in different places could be evaluated, thus broadening the application range of N-halamine-based antibacterial cotton fabrics.