scholarly journals Removal of Hg2+ From Desulfurization Wastewater By Tannin-Immobilized Graphene Oxide

2021 ◽  
Author(s):  
Heng Chen ◽  
Fengjun Liu ◽  
Chenjian Cai ◽  
Hao Wu ◽  
Linjun Yang
Keyword(s):  
Graphene Oxide ◽  
Functional Groups ◽  
Removal Efficiency ◽  
Economic Benefit ◽  
Adsorption Process ◽  
Ph Value ◽  
Low Cost ◽  
Order Kinetic ◽  
Chelation Reaction ◽  
Desulfurization Wastewater

Abstract A novel adsorbent by immobilizing tannic acid (TA) on graphene oxide (GO) was proposed and used to remove Hg2+ from desulfurization wastewater. The morphology and physic-chemical property of tannin-immobilized graphene oxide (TAIGO) was characterized by Scanning electron microscopy (SEM), Atomic Force Microscope (AFM), and Fourier transform infrared spectroscopy (FTIR). The characterization results showed that the TA was immobilized on the GO successfully, and new functional groups were introduced on TAIGO. The effect of contact time, adsorbent dose, pH, and ion components on removal efficiency were evaluated. It was found that the adsorption process would complete within 15 min, and a higher removal efficiency could be obtained on the increased adsorbent dosage. The pH value would affect the protonation process of TAIGO and the form of Hg2+ in the wastewater. The high-concertation Cl- and SO32- would hinder the absorption performance, while SO42- and cations had a negligible impact. Besides, an excellent economic benefit of TAIGO was achieved in the regeneration performance evaluation experiment, and removal efficiency of was 88% remained after three recycles. Most importantly, the TAIGO exhibited a better adsorption performance and economic benefit than GO and TA. The adsorption process was fitted with the pseudo-second-order kinetic model(R=0.9995), and the adsorption of TAIGO for Hg2+ was mainly relies on the functional groups on GO and the chelation reaction between TA and Hg2+. These facts indicated that the TAIGO was a low-cost and high removal of Hg2+ efficiency adsorbent, which could be further used in the practical desulfurization wastewater.

scholarly journals Functional Groups and Interactions Controlling the Adsorption of Bisphenol a onto Different Polymers

2009 ◽  
Vol 27 (7) ◽  
pp. 723-734 ◽  
Author(s):  
Weiben Yang ◽  
Li Ren
Keyword(s):  
Bisphenol A ◽  
Functional Groups ◽  
Adsorption Process ◽  
Ph Value ◽  
Molecular Form ◽  
Polymer Surface ◽  
Order Kinetic ◽  
Surface Complexes ◽  
Surface Areas ◽  
Pore Size Distributions

The behaviour of different polymers in the adsorption and removal of bisphenol A (BPA) from aqueous solutions was examined in order to identify the mechanism controlling the process. Three polymers with different functional groups were prepared and employed in our laboratory; they were characterized both texturally and chemically in terms of their surface areas, pore-size distributions, total exchange capacities and other parameters. The adsorption isotherms of bisphenol A were obtained and accurately modelled by the three-parameter Langmuir–Freundlich (LF) isotherm, the binding parameters calculated directly by the LF fitting coefficients indicating that increasing temperature was helpful in causing the adsorption process to move from positive cooperativity to negative cooperativity. The kinetic data were found to be well represented by the pseudo-second-order kinetic model, indicating that the functional groups of the polymers had a significant influence on the adsorption mechanism of BPA. The adsorption of BPA basically depended on the chemical nature of the polymers and the pH value of the solution. The adsorption process was favoured by the molecular form of bisphenol A, since this controlled the surface complexes produced between the polymer surface and the bisphenol A molecules, with the resulting increase in adsorbent–adsorbate interactions being positively influenced by the temperature.

scholarly journals Biosorption of Lead and Chromium Ions by Using Penicillium digitatum (Pers.) Sacc. from Industrial Water

2020 ◽  
pp. 1880-1886
Author(s):  
Sajida Frhan Hussain ◽  
Duaa Sameer Khazaal ◽  
Zainab Hani Hatif
Keyword(s):  
Heavy Metals ◽  
Functional Groups ◽  
Removal Efficiency ◽  
Adsorption Process ◽  
Low Cost ◽  
Penicillium Digitatum ◽  
Industrial Water ◽  
Ftir Analysis ◽  
Ph Values ◽  
The Fourier Transform

Some microorganisms, including fungi, are characterized by their removal efficiency and reducing the concentrations of heavy metals such as Pb and Cr from industrial water. The present study aims to estimate the efficiency of Penicillium digitatum (Pers.) Sacc. as a low-cost biosorbent in reducing Pb and Cr from industrial water with optimum biosorption conditions (acidity of 1.5 , 4, and 5; temperature of 30 °C). The Fourier transform infrared spectroscopy (FTIR) analysis was also used for determining the roles of the functional groups in this biosorbent. The results indicated that the highest P. digitatum efficiency values for reducing the levels of Pb and Cr were 84% and 70% , respectively, at pH of 5 after 24 h. However, this efficiency was decreased from  81% to76% at pH values of  4 and 1.5, respectively, for Pb. The removal efficiency for Cr was 56% at pH of 4  after 1h. at 30 °C. Also, the FTIR spectra illustrated -CH, -C-N, N-H, and =CO peaks of functional groups that may change as a result of their involvement in the adsorption process of lead and chromium.

Surface interaction of sweet potato peels (Ipomoea batata) with Cd(II) and Pb(II) ions in aqueous medium

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Aqueous Medium ◽  
Sweet Potato ◽  
Adsorption Process ◽  
Low Cost ◽  
Correlation Coefficients ◽  
Order Kinetic ◽  
Thermodynamic Evaluation ◽  
Dissociative Mechanism ◽  
Pseudo Second Order ◽  
Potato Peels

The removal of Cd(II) and Pb(II) ions from aqueous medium was studied using potato peels biomass. The adsorption process was evaluated using Atomic Absorption Spectrophotometer (AAS). The Vibrational band of the potato peels was studied using Fourier Transform Infrared Spectroscopy (FTIR). The adsorption process was carried out with respect to concentration, time, pH, particle size and the thermodynamic evaluation of the process was carried at temperatures of 30, 40, 50 and 60(0C), respectively. The FTIR studies revealed that the potato peels was composed of –OH, -NH, –C=N, –C=C and –C-O-C functional groups. The optimum removal was obtained at pH 8 and contact time of 20 min. The adsorption process followed Freundlich adsorption and pseudo second-order kinetic models with correlation coefficients (R2) greater than 0.900. The equilibrium adsorption capacity showed that Pb(II) ion was more adsorbed on the surface of the potato peels biomass versus Cd (II) ion (200.91 mg/g > 125.00 mg/g). The thermodynamic studies indicated endothermic, dissociative mechanism and spontaneous adsorption process. This study shows that sweet potato peels is useful as a low-cost adsorbent for the removal of Cd(II) and Pb(II) ions from aqueous medium.

Utilisation of Biomass and Hybrid Biochar from Elephant Grass and Low Density Polyethylene for the Competitive Adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) from Aqueous Media

2020 ◽  
Vol 13 ◽  
Author(s):  
Joshua O. Ighalo ◽  
Lois T. Arowoyele ◽  
Samuel Ogunniyi ◽  
Comfort A. Adeyanju ◽  
Folasade M. Oladipo-Emmanuel ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Removal Efficiency ◽  
Contact Time ◽  
Competitive Adsorption ◽  
Adsorption Process ◽  
Aqueous Media ◽  
Polluted Water ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Elephant Grass

Background: The presence of pollutants in polluted water is not singularized hence pollutant species are constantly in competition for active sites during the adsorption process. A key advantage of competitive adsorption studies is that it informs on the adsorbent performance in real water treatment applications. Objective: This study aims to investigate the competitive adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) using elephant grass (Pennisetum purpureum) biochar and hybrid biochar from LDPE. Method: The produced biochar was characterised by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The effect of adsorption parameters, equilibrium isotherm modelling and parametric studies were conducted based on data from the batch adsorption experiments. Results: For both adsorbents, the removal efficiency was >99% over the domain of the entire investigation for dosage and contact time suggesting that they are very efficient for removing multiple heavy metals from aqueous media. It was observed that removal efficiency was optimal at 2 g/l dosage and contact time of 20 minutes for both adsorbent types. The Elovich isotherm and the pseudo-second order kinetic models were best-fit for the competitive adsorption process. Conclusion: The study was able to successfully reveal that biomass biochar from elephant grass and hybrid biochar from LDPE can be used as effective adsorbent material for the removal of heavy metals from aqueous media. This study bears a positive implication for environmental protection and solid waste management.

Assessment of Urtica as a low-cost adsorbent for methylene blue removal: kinetic, equilibrium, and thermodynamic studies

2015 ◽  
Vol 69 (7) ◽  
Author(s):  
Mohammad Peydayesh ◽  
Mojgan Isanejad ◽  
Toraj Mohammadi ◽  
Seyed Mohammad Reza Seyed Jafari
Keyword(s):  
Methylene Blue ◽  
Adsorption Process ◽  
Low Cost ◽  
Cost Effective ◽  
Sem Analysis ◽  
Order Kinetic ◽  
Solution Ph ◽  
Factors Affecting ◽  
Order Kinetic Model ◽  
Mb Adsorption

AbstractMethylene blue (MB) removal using eco-friendly, cost-effective, and freely available Urtica was investigated. The morphology of the adsorbent surface and the nature of the possible Urtica and MB interactions were examined using SEM analysis and the FTIR technique, respectively. Various factors affecting MB adsorption such as adsorption time, initial MB concentration, temperature, and solution pH were investigated. The adsorption process was analysed using different kinetic models and isotherms. The results showed that the MB adsorption kinetic follows a pseudo-second-order kinetic model and the isotherm data fit the Langmuir isotherm well. Thermodynamic parameters, such as ΔG°, ΔH°, and ΔS°, were also evaluated, and the results indicated that the adsorption process is endothermic and spontaneous in nature. The MB adsorption capacity of Urtica was found to be as high as 101.01 mg g

scholarly journals Isotherm and Kinetic Modeling of Strontium Adsorption on Graphene Oxide

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2780
Author(s):  
Abdulrahman Abu-Nada ◽  
Ahmed Abdala ◽  
Gordon McKay
Keyword(s):  
Graphene Oxide ◽  
Aqueous Solutions ◽  
Functional Groups ◽  
Photoelectron Spectroscopy ◽  
Active Sites ◽  
Nitrogen Adsorption ◽  
Order Kinetic ◽  
X Ray ◽  
Oxygen Functional Groups ◽  
Bet Analysis

In this study, graphene oxide (GO) was synthesized using Hummers method. The synthesized GO was characterized using field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) nitrogen adsorption. The analyses confirmed the presence of oxygen functional groups (C=O and C-O-C) on the GO surface. These oxygen functional groups act as active sites in the adsorption Sr (II). The BET analysis revealed the surface area of GO of 232 m2/g with a pore volume of 0.40 cm3/g. The synthesized GO was used as an adsorbent for removing Sr (II) from aqueous solutions. The adsorption equilibrium and kinetic results were consistent with the Langmuir isotherm model and the pseudo-second-order kinetic model. A maximum strontium adsorption capacity of 131.4 mg/g was achieved. The results show that the GO has an excellent adsorption capability for removing Sr (II) from aqueous solutions and potential use in wastewater treatment applications.

scholarly journals Adsorption of azo and anthraquinone dye by using watermelon peel powder and corn peel powder: equilibrium and kinetic studies

2019 ◽  
Vol 10 (1) ◽  
pp. 4706-4713
Keyword(s):  
Ph Value ◽  
Citrullus Lanatus ◽  
Low Cost ◽  
Industrial Effluent ◽  
Essential Element ◽  
Kinetic Studies ◽  
Color Removal ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Anthraquinone Dye

Clean water is an essential element for the survival of humans and nature. However, the tremendous growth in industrialization has degraded the water quality by introducing pollutants such as dyes into the main water bodies such as rivers. In this research, the locally collected agricultural wastes such as watermelon peel (Citrullus lanatus) and corn peel (Zea Mays) were tested on two types of synthetics dyes such Remazol Brilliant Violet 5R (RBV5) and Remazol Brilliant Blue R (RBBR). From the screening test, the watermelon peel achieved the highest color removal percentage with 44.8% and followed by corn’s peel with 18.89%. Both adsorbents were selected for the batch adsorption test by varying the parameters. Based on the results achieved from the batch adsorption test, the optimum removal of dye particles was achieved at the lowest concentration of dye solutions. The optimum pH value to achieve a high percentage of color removal is at pH3, which is acidic. In this case, the 3 g of adsorbent dosage achieved the highest percentage of color removal compared to 5 g. This could due to insufficient contact time. In addition, the chemical and physical characteristics of the adsorbents were analyzed using FESEM and FTIR respectively. By analyzing the surface texture and functional group, differences in the adsorbents before and after adsorption were noticed. Besides that, based on the obtained R2 values from the linear plotting, the Temkin isotherm model and pseudo-second-order kinetic model fitted well compared to other isotherm and kinetic models. In conclusion, the watermelon peel and corn peel are capable of removing dye particles in the industrial effluent under selective conditions with low cost while being environmentally friendly.

scholarly journals Enhanced removal of ibuprofen by heterogeneous photo-Fenton like process over sludge based Fe3O4-MnO2 catalysts

2021 ◽  
Author(s):  
Yanjun Liu ◽  
Xiaoqian Zheng ◽  
Shufen Zhang ◽  
Shujuan Sun
Keyword(s):  
Catalytic Mechanism ◽  
Ph Value ◽  
Low Cost ◽  
Degradation Process ◽  
Hydroxyl Groups ◽  
Order Kinetic ◽  
Product Analysis ◽  
Experimental Conditions ◽  
Preparation Conditions ◽  
Nano Fe3o4

Abstract Heterogeneous photo-Fenton like catalysts with low cost, little hazardous, high effective and facile separation from aqueous solution were highly desirable. In this study, sludge-based catalysts combining nano Fe3O4-MnO2 and sludge activated carbon were successfully synthesized by high-temperature calcination method and then characterized. These synthetic materials were applied to remove ibuprofen in the heterogeneous photo-Fenton process. The preparation conditions of sludge-based catalysts optimized by orthogonal experiments were 2.0 M of ZnCl2, a temperature of 500 °C, a pyrolysis time of 60 min, and a sludge ratio: Fe3O4-MnO2 of 25:2. In batch experiments, the optimal experimental conditions were determined as catalyst dosage of 0.4 g·L−1, hydrogen peroxide concentration of 3.0 g·L−1, pH value of 3.3, and contact time of 2.5 h. The degradation rate Sludge/Fe3O4-MnO2 catalyst to ibuprofen is up to 95%. The removal process of ibuprofen fitted the pseudo-second-order kinetic model, and the photocatalytic degradation process was the main factor controlling the reaction rate. The catalytic mechanism was proposed according to the FTIR analysis and mass spectrometry product analysis, it was mainly attributed to the interaction between hydroxyl groups and benzene rings.

scholarly journals Kinetics, Isotherm and Thermodynamic Studies for Efficient Adsorption of Congo Red Dye from Aqueous Solution onto Novel Cyanoguanidine-Modified Chitosan Adsorbent

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4446
Author(s):  
Nouf F. Al-Harby ◽  
Ebtehal F. Albahly ◽  
Nadia A. Mohamed
Keyword(s):  
Aqueous Solution ◽  
Congo Red ◽  
Adsorption Process ◽  
Ph Value ◽  
Dye Adsorption ◽  
Order Kinetic ◽  
Amino Groups ◽  
Solution Ph ◽  
Intraparticle Diffusion Model ◽  
Modified Chitosan

Novel Cyanoguanidine-modified chitosan (CCs) adsorbent was successfully prepared via a four-step procedure; first by protection of the amino groups of chitosan, second by insertion of epoxide rings, third by opening the latter with cyanoguanidine, and fourth by restoring the amino groups through elimination of the protection. Its structure and morphology were checked using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The adsorption capacity of CCs for Congo Red (CR) dye was studied under various conditions. It decreased significantly with the increase in the solution pH value and dye concentration, while it increased with increasing temperature. The adsorption fitted to the pseudo-second order kinetic model and Elovich model. The intraparticle diffusion model showed that the adsorption involved a multi-step process. The isotherm of CR dye adsorption by CCs conforms to the Langmuir isotherm model, indicating the monolayer nature of adsorption. The maximum monolayer coverage capacity, qmax, was 666.67 mg g−1. Studying the thermodynamic showed that the adsorption was endothermic as illustrated from the positive value of enthalpy (34.49 kJ mol−1). According to the values of ΔG°, the adsorption process was spontaneous at all selected temperatures. The value of ΔS° showed an increase in randomness for the adsorption process. The value of activation energy was 2.47 kJ mol−1. The desorption percentage reached to 58% after 5 cycles. This proved that CCs is an efficient and a promising adsorbent for the removal of CR dye from its aqueous solution.

Comparative MCDM Analysis for AMD Treatment Method Selection

2021 ◽  
Author(s):  
Zoran Štirbanović ◽  
Vojka Gardić ◽  
Dragiša Stanujkić ◽  
Radmila Marković ◽  
Jovica Sokolović ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Metal Ions ◽  
Adsorption Process ◽  
Mine Drainage ◽  
Ph Value ◽  
Low Cost ◽  
Treatment Method ◽  
Passive Treatment ◽  
Copper Production ◽  
Capital Costs

Abstract Robule Lake is located in Eastern Serbia, near city of Bor, known for copper production, and it is being influenced by waste materials from mining activities. For the purification of water from Robule Lake, contaminated with various metal ions (Fe, Cu, Zn, Mn, Cd, Ni, etc.), acid mine drainage (AMD) treatment methods such as: passive treatment method, sequential neutralization, ion exchange, adsorption process based on low cost adsorbents, adsorption process based on natural zeolits, electrodialysis, filtration with nanofiltration membranes, and reverse osmosis, were evaluated by following MCDM methods: TOPSIS, VIKOR, MOOSRA; WASPAS, and CoCoSo. Criteria used for the evaluation were: efficiency in the metal ions removal and the quality of the purified water, necessity of pre-treatment and / or post-treatment of treated water, possibility of using the generated waste, capital costs, operating and maintenance costs, needed area, and sensitivity of the method. The results of the MCDM analysis showed that sequential neutralization was the most appropriate for this wastewater, while passive treatment system and ion exchange were ranked as second and third, respectively.After the selection of AMD treatment method, neutralization tests with lime were carried out on the water sample from Robule Lake. The results of sequential neutralization testing showed that concentration of Fe ions could be lowered below the maximal allowable concentration prescribed by Serbian legislation at pH value 4. The other metal ions: Cu, Zn, and Ni needed pH value 7, and Mn and Cd needed pH 10 for effective removal.

Sign in / Sign up

Export Citation Format

Share Document