On the Understanding of the Adsorption of 2-Phenylethanol on Polyurethane-Keratin based Membranes

Abstract Polymers and specifically hybrid polymeric membranes have been identified as effective formulations in adsorption processes. Nevertheless, the adsorption mechanisms associated with their thermodynamics and kinetics are not fully understood, particularly when these polymeric membranes are used to adsorb 2-Phenylethanol (2-PE) to intensify its production in a specific bioconversion process. This work was aimed at giving phenomenological insights on the adsorption of 2-PE on a set of novel porous hybrid membranes based on polyurethane and keratin biofiber obtained from chicken feathers. Feathers, considered as a waste by-product of the poultry industry, represent an alternative source of keratin, a biopolymer that can be used to design low-cost materials from natural resources. Two types of hybrid membranes were prepared. i. e. composite and copolymer. Firstly, these materials were characterized by scanning electron microscopy (SEM), infrared spectroscopy (FT-IR) (before and after the adsorption process) and X-Ray (WAXD) analysis. Secondly, these materials, including the reference ones (keratin biofiber and polyurethane), were evaluated during the removal of 2-PE, relating their adsorption capabilities to physiochemical properties elucidated during the characterization. Particularly a composite with 0.1 g of chicken-feather-keratin (C1) presented the highest removal percentage (60.68%), a significant initial adsorption rate (0.2340 mgPE.h−1.gA −1), the maximum adsorption capacity (12.13 mgPE.gA −1) and the best stability and mechanical properties at studied operating conditions. In comparison with results reported in literature, in this composite carbonyl functional groups from polyurethane showed rather major affinity to 2-PE than amino groups from the keratin biofiber. To this end, parameters associated with its industrial application were obtained, namely thermodynamic and kinetic information was obtained from a proper design of experiments and phenomenological models based on adsorption macroscopic fundamentals.

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Comparison of the fixation of several metal ions onto a low-cost biopolymer

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0172 ◽

2002 ◽

Vol 2 (5-6) ◽

pp. 217-224 ◽

Cited By ~ 6

Author(s):

Z. Reddad ◽

C. Gérente ◽

Y. Andrès ◽

P. Le Cloirec

Keyword(s):

Aqueous Solutions ◽

Metal Ions ◽

Low Cost ◽

Operating Conditions ◽

Order Kinetic ◽

Adsorption Mechanisms ◽

Equilibrium Data ◽

Order Kinetic Model ◽

Beet Pulp ◽

Removal Of Metal Ions

In the present work, sugar beet pulp, a common waste from the sugar refining industry, was studied in the removal of metal ions from aqueous solutions. The ability of this cheap biopolymer to sorb several metals namely Pb2+, Cu2+, Zn2+, Cd2+ and Ni2+ in aqueous solutions was investigated. The metal fixation capacities of the sorbent were determined according to operating conditions and the fixation mechanisms were identified. The biopolymer has shown high elimination rates and interesting metal fixation capacities. A pseudo-second-order kinetic model was tested to investigate the adsorption mechanisms. The kinetic parameters of the model were calculated and discussed. For 8 × 10-4 M initial metal concentration, the initial sorption rates (v0) ranged from 0.063 mmol.g-1.min-1 for Pb2+ to 0.275 mmol.g-1.min-1 for Ni2+ ions, with the order: Ni2+ > Cd2+ > Zn2+ > Cu2+ > Pb2+. The equilibrium data fitted well with the Langmuir model and showed the following affinity order of the material: Pb2+ > Cu2+ > Zn2+ > Cd2+ > Ni2+. Then, the kinetic and equilibrium parameters calculated qm and v0 were tentatively correlated to the properties of the metals. Finally, equilibrium experiments in multimetallic systems were performed to study the competition of the fixation of Pb2+, Zn2+ and Ni2+ cations. In all cases, the metal fixation onto the biopolymer was found to be favourable in multicomponent systems. Based on these results, it is demonstrated that this biosorbent represents a low-cost solution for the treatment of metal-polluted wastewaters.

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Modified Vermiculite as Adsorbent of Hexavalent Chromium in Aqueous Solution

Minerals ◽

10.3390/min10090749 ◽

2020 ◽

Vol 10 (9) ◽

pp. 749

Author(s):

Celia Marcos ◽

Valeria Medoro ◽

Alaa Adawy

Keyword(s):

Adsorption Capacity ◽

Adsorption Energy ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Ion Chemistry ◽

Solution Ph ◽

Cooperative Process ◽

Order Kinetic Model ◽

Initial Adsorption ◽

Initial Adsorption Rate

The aim of this study was to investigate the efficiency of removing Cr6+ from aqueous solutions using two exfoliated vermiculite: (1) heated abruptly at 1000 °C and (2) irradiated with microwave radiation. The effects investigated were contact time, adsorbate concentration and initial Cr6+ concentration. The adsorption with both exfoliated vermiculites was well described by the DKR isotherm, indicative of a cooperative process and with the pseudo second order kinetic model. The Kd value for the two exfoliated vermiculites was similar, 0.2 ·1010 μg/Kg. The maximum adsorption capacity of Cr6+ with thermo-exfoliated vermiculite, 2.81 mol/g, was much higher than with microwave irradiated vermiculite, 0.001 mol/g; both values were obtained with 0.5 g of vermiculite in contact with distilled water enriched with 1 ppm of Cr6+ for 24 h. Factors such as ion chemistry, the solution pH and ionic strength, influence the values of capacity, adsorption energy and initial adsorption rate values of the exfoliated vermiculite. In addition, these values depended on the exfoliation process, being the adsorption capacity highest with abrupt heating of vermiculite, while the adsorption energy and rate values showed just a slight increase with microwave irradiation. This aspect is important to select the most suitable vermiculite modification treatment to use it as an adsorbent.

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Functionalized Porous Nanoscale Fe3O4 Particles Supported Biochar From Peanut Shell For Pb(II) Ions Removal From Landscape Wastewater

10.21203/rs.3.rs-981230/v1 ◽

2021 ◽

Author(s):

Xiaojun Jin ◽

Renrong Liu ◽

Huifang Wang ◽

Li Han ◽

Muqing Qiu ◽

...

Keyword(s):

Heavy Metal ◽

High Efficiency ◽

Adsorption Process ◽

Low Cost ◽

Agricultural Waste ◽

Maximum Adsorption Capacity ◽

Complexation Reaction ◽

Order Kinetic ◽

Peanut Shell ◽

Adsorption Mechanisms

Abstract The large amounts of heavy metal from landscape wastewater have become serious problems of environmental pollution and risks for human health. It affects the growth of plant and aquatic, and leads to the destruction of landscape. Therefore, the development of efficient novel adsorbent is a very important for treatment of heavy metal. A low-cost and easily obtained agricultural waste (Peanut Shell) was modified by nanoscale Fe3O4 particles. Then, the functionalized porous nanoscale Fe3O4 particles supported biochar from peanut shell (PS-Fe3O4) for removal of Pb(II) ions from aqueous solution was investigated. The characterization of PS-Fe3O4 composites showed that PS from peanut shell was successfully coated with porous nanoscale Fe3O4 particles. The pseudo second-order kinetic model and Langmuir model were more fitted for describing the adsorption process of Pb(II) ions in solution. The maximum adsorption capacity of Pb(II) ions removal in solution by PS-Fe3O4 composites could reach 188.68 mg/g. The adsorption process of Pb(II) ions removal by PS-Fe3O4 composites was a spontaneous and endothermic process. The adsorption mechanisms of Pb(II) ions by PS-Fe3O4 composites were mainly controlled by the chemical adsorption process. They included Fe-O coordination reaction, co-precipitation, complexation reaction and ion exchange. PS-Fe3O4 composites were thought as a low-cost, good regeneration performance and high efficiency adsorption material for removal of Pb(II) ions in solution.

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Efficient Removal of Aqueous Manganese (II) Cations by Activated Opuntia Ficus Indica Powder: Adsorption Performance and Mechanism

Acta Chimica Slovenica ◽

10.17344/acsi.2020.6248 ◽

2021 ◽

Vol 68 (3) ◽

pp. 548-561

Author(s):

Boutheina Djobbi ◽

Ghofrane Lassoued Ben Miled ◽

Hatem Raddadi ◽

Rached Ben Hassen

Keyword(s):

Adsorption Mechanism ◽

Low Cost ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

Opuntia Ficus Indica ◽

Adsorption Mechanisms ◽

Manganese Ion ◽

Manganese Removal ◽

Surface Areas ◽

Pseudo Second Order

The adsorption of manganese ions from aqueous solutions by pure and acid-treated Opuntia ficus indica as natural low-cost and eco-friendly adsorbents was investigated. The adsorbents’ structures were characterized by powder X-ray diffraction and infrared spectroscopy. Specific surface areas were determined using the Brunauer-Emmett-Tell equation. The study was carried out under various parameters influencing the manganese removal efficiency such as pH, temperature, contact time, adsorbent dose and initial concentration of manganese ion. The maximum adsorption capacity reached 42.02 mg/g for acid-treated Opuntia ficus indica, and only 20.8 mg /g for pure Opuntia ficus indica. The Langmuir, Freundlich and Temkin isotherms equations were tested, and the best fit was obtained by the Langmuir model for both adsorbents. The thermodynamic study shows that chemisorption is the main adsorption mechanism for the activated adsorbent while physisorption is the main adsorption mechanism for the pure adsorbent. The kinetics of the adsorption have been studied using four kinetics models of pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion. Structural analyses indicate the appearance of MnOx oxides on the cellulose fibers. The adsorption mechanisms consist of an electrostatic interaction followed by oxidation of the Mn (II) to higher degrees, then probably by binding to the surface of the adsorbent by different C-O-MnOx bonds.

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Porous Activated Carbon from Lignocellulosic Agricultural Waste for the Removal of Acetampirid Pesticide from Aqueous Solutions

Molecules ◽

10.3390/molecules25102339 ◽

2020 ◽

Vol 25 (10) ◽

pp. 2339 ◽

Cited By ~ 1

Author(s):

Somaia G. Mohammad ◽

Sahar M. Ahmed ◽

Abd El-Galil E. Amr ◽

Ayman H. Kamel

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Adsorption Process ◽

Low Cost ◽

Agricultural Waste ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Equilibration Time ◽

Freundlich Isotherms ◽

Before And After

A facile eco-friendly approach for acetampirid pesticide removal is presented. The method is based on the use of micro- and mesoporous activated carbon (TPAC) as a natural adsorbent. TPAC was synthesized via chemical treatment of tangerine peels with phosphoric acid. The prepared activated carbon was characterized before and after the adsorption process using Fourier- transform infrared (FTIR), X-ray diffraction (XRD), particle size and surface area. The effects of various parameters on the adsorption of acetampirid including adsorbent dose (0.02–0.2 g), pH 2–8, initial adsorbate concentration (10–100 mg/L), contact time (10–300 min) and temperature (25–50 °C) were studied. Batch adsorption features were evaluated using Langmuir and Freundlich isotherms. The adsorption process followed the Langmuir isotherm model with a maximum adsorption capacity of 35.7 mg/g and an equilibration time within 240 min. The adsorption kinetics of acetamiprid was fitted to the pseudo-second-order kinetics model. From the thermodynamics perspective, the adsorption was found to be exothermic and spontaneous in nature. TPAC was successfully regenerated and reused for three consecutive cycles. The results of the presented study show that TPAC may be used as an effective eco-friendly, low cost and highly efficient adsorbent for the removal of acetamiprid pesticides from aqueous solutions.

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Adsorption of Chromium(VI) onto Freshwater Snail Shell-Derived Biosorbent from Aqueous Solutions: Equilibrium, Kinetics, and Thermodynamics

Journal of Chemistry ◽

10.1155/2019/3038103 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Xuan Hoa Vu ◽

Lan Huong Nguyen ◽

Huu Tap Van ◽

Dinh Vinh Nguyen ◽

Thu Huong Nguyen ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solutions ◽

Contact Time ◽

Low Cost ◽

Freshwater Snail ◽

Isotherm Models ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Adsorption Mechanisms

In this study, freshwater snail shells (FSSs) containing CaCO3 were used as a low-cost biosorbent for removing Cr(VI) from aqueous solutions. The characteristics of FSS and mechanism of Cr(VI) adsorption onto FSS were investigated. The FSS biosorbent was characterized using nitrogen adsorption/desorption isotherm, X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, and Fourier transform infrared spectroscopy. The adsorption mechanism was determined by conducting various batch adsorption experiments along with fitting experimental data with various adsorption models. Batch adsorption experiments were conducted as a function of solution pH, contact time, biosorbent dose, and initial Cr(VI) concentration. Results indicated that pH = 2, a contact time of 120 min, and an initial Cr(VI) concentration of 30 mg/L at 20°C were the best conditions for adsorption of Cr(VI) onto FSS. The Cr(VI) adsorption onto FSS decreased with an increase in temperature from 20 to 40°C. The obtained maximum adsorption capacity was 8.85 mg/g for 2 g/L of FSS dose with 30 mg/L of initial Cr(VI) at 20°C. The adsorption equilibrium data fit well with the Sips and Langmuir isotherm models at 20°C with a high R2 of 0.981 and 0.975, respectively. Also, a good correlation between the experimental data and the pseudo-second-order model was achieved, with the highest R2 of 0.995 at 20°C. The adsorption mechanisms were electrostatic interaction and ion exchange. Simultaneously, this mechanism was also controlled by film diffusion. The Cr(VI) adsorption process was irreversible, spontaneous (−∆G°), exothermic (∆H° is negative), and less random (∆S° is negative). In conclusion, freshwater snail shells have the potential as a renewable adsorbent to remove toxic metals from wastewater.

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Parameters Affecting Dye Adsorption - Using Graphene Coated Sand (GSC)

International Journal of Science and Engineering Invention ◽

10.23958/ijsei/vol04-i02/01 ◽

2018 ◽

Vol 4 (02) ◽

Author(s):

Seroor Atalah Khaleefa Alia ◽

Dr. Mohammed Ibrahimb ◽

Hussein Ali Hussein

Keyword(s):

Heavy Metals ◽

Contact Time ◽

Organic Dyes ◽

Low Cost ◽

Dye Adsorption ◽

Contaminated Water ◽

Maximum Adsorption Capacity ◽

Engineering Designs ◽

Heavy Metals Ions ◽

Coated Sand

Adsorption is most commonly applied process for the removal of pollutants such as dyes and heavy metals ions from wastewater. The present work talks about preparing graphenic material attached sand grains called graphene sand composite (GSC) by using ordinary sugar as a carbon source. Physical morphology and chemical composition of GSC was examined by using (FTIR, SEM, EDAX and XRD). Efficiency of GSC in the adsorption of organic dyes from water was investigated using reactive green dye with different parameters such as (ph, temperature, contact time and dose). Adsorption isotherm was also studied and the results showed that the maximum adsorption capacity of dye is 28.98 mg/g. This fast, low-cost process can be used to manufacture commercial filters to treat contaminated water using appropriate engineering designs.

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The Iterative Development and Testing of an Interactive Mobile Application for Skill Retention of Cardiopulmonary Resuscitation Among High School Students: A Pilot Study

Simulation & Gaming ◽

10.1177/10468781211032692 ◽

2021 ◽

pp. 104687812110326

Author(s):

Adeel Arif ◽

Amber Arif ◽

Kimberly Anne Fasciglione ◽

Farrukh Nadeem Jafri

Keyword(s):

High School ◽

High School Students ◽

Cardiopulmonary Resuscitation ◽

Mobile Apps ◽

Low Cost ◽

Survival Rates ◽

Compression Rate ◽

School Students ◽

Skill Retention ◽

Before And After

Abstract: Background Locations concentrated with High School (HS) students tend to have lower out-of-hospital cardiac arrest (OHCA) survival rates. Mobile applications (apps) have the capability to augment cardiopulmonary resuscitation (CPR) skill retention as a low-cost, accessible training method. Methods An iterative process to develop an app to reinforce CPR skills emphasizing hand placement, compression rate, real-time feedback, and recurring tips is described. The app was tested on HS students to measure its impact on quality and comfort of CPR using Likert surveys and skills assessments before and after one month of usage. CPR Score and compression rate were measured using the Laerdal™ Little Anne Manikin QCPR software. Results Fourteen HS students participated in a prospective observational study. It was found that the use of the developed app was associated with improved CPR performance (80.43% v. 87.86%, p=0.01-0.02, 95% CI=2.20-12.66) after one month. Additionally, improvements were demonstrated in compression rate accuracy (21.43% v. 64.29%, p=0.041, 95% CI=0.132-0.725), increased comfort performing CPR (3.86 v. 4.79, p<0.001, 95% CI =0.99-1.00) and comfort performing CPR on strangers (2.71 v. 4.42, p<0.001, 95% CI=1.24-2.19). In addition, for every time the app was used, CPR performance increased by 0.5668% (p=0.0182). Conclusion Findings suggest that mobile apps may have promising implications as augmentative tools for CPR curriculums.

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Micromagnetic Characterization of Operation-Induced Damage in Charpy Specimens of RPV Steels

Applied Sciences ◽

10.3390/app11072917 ◽

2021 ◽

Vol 11 (7) ◽

pp. 2917

Author(s):

Madalina Rabung ◽

Melanie Kopp ◽

Antal Gasparics ◽

Gábor Vértesy ◽

Ildikó Szenthe ◽

...

Keyword(s):

Neutron Irradiation ◽

Pressure Vessel ◽

Operating Conditions ◽

Magnetic Characteristics ◽

Pressure Vessel Steel ◽

Training Procedure ◽

Vessel Steel ◽

Before And After ◽

The Individual ◽

Magnetic Adaptive Testing

The embrittlement of two types of nuclear pressure vessel steel, 15Kh2NMFA and A508 Cl.2, was studied using two different methods of magnetic nondestructive testing: micromagnetic multiparameter microstructure and stress analysis (3MA-X8) and magnetic adaptive testing (MAT). The microstructure and mechanical properties of reactor pressure vessel (RPV) materials are modified due to neutron irradiation; this material degradation can be characterized using magnetic methods. For the first time, the progressive change in material properties due to neutron irradiation was investigated on the same specimens, before and after neutron irradiation. A correlation was found between magnetic characteristics and neutron-irradiation-induced damage, regardless of the type of material or the applied measurement technique. The results of the individual micromagnetic measurements proved their suitability for characterizing the degradation of RPV steel caused by simulated operating conditions. A calibration/training procedure was applied on the merged outcome of both testing methods, producing excellent results in predicting transition temperature, yield strength, and mechanical hardness for both materials.

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Innovative passive reinforcements for the gradual stabilization of a landslide according with the observational method

Landslides ◽

10.1007/s10346-021-01638-0 ◽

2021 ◽

Author(s):

Lorenzo Brezzi ◽

Alberto Bisson ◽

Davide Pasa ◽

Simonetta Cola

Keyword(s):

Monitoring System ◽

Low Cost ◽

Economic Losses ◽

Fe Model ◽

Site Conditions ◽

Observational Method ◽

Rainy Period ◽

Sustainable Solutions ◽

Before And After ◽

Set Up

AbstractA large number of landslides occur in North-Eastern Italy during every rainy period due to the particular hydrogeological conditions of this area. Even if there are no casualties, the economic losses are often significant, and municipalities frequently do not have sufficient financial resources to repair the damage and stabilize all the unstable slopes. In this regard, the research for more economically sustainable solutions is a crucial challenge. Floating composite anchors are an innovative and low-cost technique set up for slope stabilization: it consists in the use of passive sub-horizontal reinforcements, obtained by coupling a traditional self-drilling bar with some tendons cemented inside it. This work concerns the application of this technique according to the observational method described within the Italian and European technical codes and mainly recommended for the design of geotechnical works, especially when performed in highly uncertain site conditions. The observational method prescribes designing an intervention and, at the same time, using a monitoring system in order to correct and adapt the project during realization of the works on the basis of new data acquired while on site. The case study is the landslide of Cischele, a medium landslide which occurred in 2010 after an exceptional heavy rainy period. In 2015, some floating composite anchors were installed to slow down the movement, even if, due to a limited budget, they were not enough to ensure the complete stabilization of the slope. Thanks to a monitoring system installed in the meantime, it is now possible to have a comparison between the site conditions before and after the intervention. This allows the evaluation of benefits achieved with the reinforcements and, at the same time, the assessment of additional improvements. Two stabilization scenarios are studied through an FE model: the first includes the stabilization system built in 2015, while the second evaluates a new solution proposed to further increase the slope stability.

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