Synthesis of Modified Metal Organic Skeleton and Its Adsorption of Hydrochloric Acid Wastewater, Mercury and Arsenic in Water

Metal organic skeleton (MOFs) is a kind of porous material composed of metal ions and organic ligands through coordination, which can be used to absorb a lot of toxic substances from waste water. In this research, UiO-66, UiO-66(Zr) and UiO-66(Zr)–2COOH were synthesized by solvent thermal method, and physical analysis was conducted on the adsorbent properties of the materials by means of XRD, IR, Zeta potential, etc. In the adsorption test of wastewater impurities, UiO-66(Zr)–2COOH was firstly taken as the research object. With the increase of the initial concentration of hydrochloric acid, the adsorption capacity of the organic skeleton was greatly increased. However, when the concentration increases further, the growth rate of adsorption decreases, and with the increase of temperature, the adsorption decreases further. The organic skeleton of Hg(II) adsorption process conforms to the secondary dynamic adsorption model. At the same time, the organic skeleton materials of Hg(II) has strong ability of recognition, the recognition of Hg(II) sex is much stronger than the Ni(II) identification. Uio-66(Zr) and UiO-66(Zr)–2COOH are selected for adsorption of As, and the adsorption process of the two kinds of materials of As is close to the Freundlich model(III). The ability of absorbing As(III) of these materials is stronger than the ability of As(V). At the same time, UiO-66(Zr)–2COOH shows higher adsorption capacity on the As(III), and maximum adsorption capacity is 220 mg/g.

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Full Factorial Design for Gold Recovery from Industrial Solutions

Toxics ◽

10.3390/toxics9050111 ◽

2021 ◽

Vol 9 (5) ◽

pp. 111

Author(s):

Maria Mihăilescu ◽

Adina Negrea ◽

Mihaela Ciopec ◽

Petru Negrea ◽

Narcis Duțeanu ◽

...

Keyword(s):

Factorial Design ◽

Adsorption Capacity ◽

Contact Time ◽

Adsorption Process ◽

Design Method ◽

Precious Metals ◽

Gold Recovery ◽

Maximum Adsorption Capacity ◽

Gold Concentration ◽

Commercial Resin

Gold is one of the precious metals with multiple uses, whose deposits are much smaller than the global production needs. Therefore, extracting maximum gold quantities from industrial diluted solutions is a must. Am-L-GA is a new material, obtained by an Amberlite XAD7-type commercial resin, functionalized through saturation with L-glutamic acid, whose adsorption capacity has been proved to be higher than those of other materials utilized for gold adsorption. In this context, this article presents the results of a factorial design experiment for optimizing the gold recovery from residual solutions resulting from the electronics industry using Am-L-GA. Firstly, the material was characterized using atomic force microscopy (AFM), to emphasize the material’s characteristics, essential for the adsorption quality. Then, the study showed that among the parameters taken into account in the analysis (pH, temperature, initial gold concentration, and contact time), the initial gold concentration in the solution plays a determinant role in the removal process and the contact time has a slightly positive effect, whereas the pH and temperature do not influence the adsorption capacity. The maximum adsorption capacity of 29.27 mg/L was obtained by optimizing the adsorption process, with the control factors having the following values: contact time ~106 min, initial Au(III) concentration of ~164 mg/L, pH = 4, and temperature of 25 °C. It is highlighted that the factorial design method is an excellent instrument to determine the effects of different factors influencing the adsorption process. The method can be applied for any adsorption process if it is necessary to reduce the number of experiments, to diminish the resources or time consumption, or for expanding the investigation domain above the experimental limits.

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Fabrication of Carboxymethylcellulose/Metal-Organic Framework Beads for Removal of Pb(II) from Aqueous Solution

Materials ◽

10.3390/ma12060942 ◽

2019 ◽

Vol 12 (6) ◽

pp. 942 ◽

Cited By ~ 10

Author(s):

Huo-Xi Jin ◽

Hong Xu ◽

Nan Wang ◽

Li-Ye Yang ◽

Yang-Guang Wang ◽

...

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Langmuir Isotherm ◽

Adsorption Equilibrium ◽

Isotherm Model ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Metal Organic ◽

Langmuir Isotherm Model

The ability to remove toxic heavy metals, such as Pb(II), from the environment is an important objective from both human-health and ecological perspectives. Herein, we describe the fabrication of a novel carboxymethylcellulose-coated metal organic material (MOF-5–CMC) adsorbent that removed lead ions from aqueous solutions. The adsorption material was characterized by Fourier-transform infrared spectroscopy, X-ray diffractometry, scanning electron microscopy, and X-ray photoelectron spectroscopy. We studied the functions of the contact time, pH, the original concentration of the Pb(II) solution, and adsorption temperature on adsorption capacity. MOF-5–CMC beads exhibit good adsorption performance; the maximum adsorption capacity obtained from the Langmuir isotherm-model is 322.58 mg/g, and the adsorption equilibrium was reached in 120 min at a concentration of 300 mg/L. The adsorption kinetics is well described by pseudo-second-order kinetics, and the adsorption equilibrium data are well fitted to the Langmuir isotherm model (R2 = 0.988). Thermodynamics experiments indicate that the adsorption process is both spontaneous and endothermic. In addition, the adsorbent is reusable. We conclude that MOF-5–CMC is a good adsorbent that can be used to remove Pb(II) from aqueous solutions.

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Ouricuri (Syagrus coronata) fiber: a novel biosorbent to remove methylene blue from aqueous solutions

Water Science & Technology ◽

10.2166/wst.2016.495 ◽

2016 ◽

Vol 75 (1) ◽

pp. 106-114 ◽

Cited By ~ 19

Author(s):

Lucas Meili ◽

Társila Santos da Silva ◽

Daniely Carlos Henrique ◽

João Inácio Soletti ◽

Sandra Helena Vieira de Carvalho ◽

...

Keyword(s):

Methylene Blue ◽

Experimental Design ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Adsorption Process ◽

Fiber Diameter ◽

Aqueous Media ◽

Process Efficiency ◽

Maximum Adsorption Capacity ◽

Equilibrium Studies

In this work, the potential of ouricuri (Syagrus coronata) fiber as a novel biosorbent to remove methylene blue (MB) from aqueous solutions was investigated. The fiber was prepared and characterized according to the fundamental features for adsorption. A 23 experimental design was used to evaluate the effects of adsorbent dosage (M), fiber diameter (D) and agitation (A) on the adsorption capacity. In the more adequate conditions, kinetic and equilibrium studies were performed. The experimental design results showed that M = 10 g L−1), D = 0.595 mm and A = 200 rpm were the more adequate conditions for MB adsorption. Based on the kinetic study, it was found that the adsorption process was fast, being the equilibrium was attained at about 5 min, with 90% of color removal. The isotherm was properly represented by the Sips model, and the maximum adsorption capacity was 31.7 mg g−1. In brief, it was demonstrated that ouricuri fiber is an alternative biosorbent to remove MB from aqueous media, taking into account the process efficiency and economic viewpoint.

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Synergistic effect of carboxyl and sulfate groups for effective removal of radioactive strontium ion in a Zr-metal-organic framework

Water Science & Technology ◽

10.2166/wst.2021.103 ◽

2021 ◽

Author(s):

Lin Ren ◽

Xudong Zhao ◽

Baosheng Liu ◽

Hongliang Huang

Keyword(s):

Adsorption Capacity ◽

High Efficiency ◽

Metal Organic Framework ◽

Maximum Adsorption Capacity ◽

Potential Candidate ◽

Dual Groups ◽

Metal Organic ◽

Strontium Ion ◽

Rapid Adsorption ◽

Organic Framework

Abstract Rapid removal of radioactive strontium from nuclear wastewater is of great significance for environment safety and human health. This work reported the effective adsorption of strontium ion in a stable dual-group metal-organic framework, Zr6(OH)14(BDC-(COOH)2)4(SO4)0.75 (Zr-BDC-COOH-SO4), which contains strontium-chelating groups (-COOH and SO4) and strongly ionizable group (-COOH). Zr-BDC-COOH-SO4 exhibits very rapid adsorption kinetics (<5 min) and a maximum adsorption capacity of 67.5 mg g−1. The adsorption behaviors can be well evaluated by pseudo-second-order model and Langmuir isotherm model. Further investigations indicate that the adsorption of Sr2+ in Zr-BDC-COOH-SO4 would not be interfered by solution pH and adsorption temperature obviously. Feasible regeneration of the adsorbent was also demonstrated through a simple elution method. Mechanism investigation suggests that free -COOH contributes to the rapid adsorption based on electrostatic interaction while introduction of -SO4 can enhance the adsorption capacity largely. Thus, these results suggest that Zr-BDC-COOH-SO4 might be a potential candidate for Sr2+ removal and introducing dual groups is an effective strategy for designing high-efficiency adsorbents.

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Adsorption Capacity of Ca2+ by Hydrochloric Acid Activated Kaolin

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/926/1/012082 ◽

2021 ◽

Vol 926 (1) ◽

pp. 012082

Author(s):

N Wahyuni

Keyword(s):

Hydrochloric Acid ◽

Adsorption Capacity ◽

Calcium Ions ◽

Contact Time ◽

Maximum Adsorption Capacity ◽

High Concentration ◽

Straightforward Method ◽

Diamine Tetraacetate ◽

Ca Ions ◽

Time Variations

Abstract A high concentration of calcium ions in water is a problem as it can cause blockages in engine pipes. Adsorption is a relatively cheap and straightforward method that can be used to reduce the calcium ion content in water. Kaolin is a mineral that has a potential as an adsorbent and whose adsorption capacity can be increased by activation. This research studied the adsorption capacity of activated kaolin by hydrochloric acid against Ca2+ ions. Kaolin was chemically activated using 6 M HCl solution for 24 hours. The adsorption contact time in batches was varied with time variations of 30, 90, 150, and 180 minutes. The maximum adsorption capacity of activated kaolin to the Ca2+ was determined by varying the initial concentrations of water samples, namely 4, 7, 10, and 13 mg/L. The concentration of Ca2+ was determined by a titration method using ethylene diamine tetraacetate (EDTA). The results showed that the activation of kaolin with 6 M HCl at the optimum contact time of adsorption, namely 150 minutes, increased the percentage of adsorbed Ca ions to 2 times of that of natural kaolin, from 33.3% to 68.3%. Based on the Langmuir equation, the maximum adsorption capacity of calcium ions by activated kaolin HCl 6 M increased 1.7 times from natural kaolin to 0.346 mg/g.

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Modified/Unmodified Nanoparticle Adsorbents of Cellulose Origin With High Adsorptive Potential for Removal of Pb(II) From Aqueous Solution

European Scientific Journal ESJ ◽

10.19044/esj.2017.v13n27p425 ◽

2017 ◽

Vol 13 (27) ◽

pp. 425

Author(s):

Azeh Yakubu ◽

Gabriel Ademola Olatunji ◽

Folahan Amoo Adekola

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Contact Time ◽

Adsorption Process ◽

Correlation Coefficients ◽

Solution Temperature ◽

Isotherm Models ◽

Maximum Adsorption Capacity ◽

Kinetics Of Adsorption ◽

Kinetics Of

This investigation was conducted to evaluate the adsorption capacity of nanoparticles of cellulose origin. Nanoparticles were synthesized by acid hydrolysis of microcrystalline cellulose/cellulose acetate using 64% H3PO4 and characterized using FTIR, XRD, TGA-DTGA, BET and SEM analysis. Adsorption kinetics of Pb (II) ions in aqueous solution was investigated and the effect of initial concentration, pH, time, adsorbent dosage and solution temperature. The results showed that adsorption increased with increasing concentration with removal efficiencies of 60% and 92.99% for Azeh2 and Azeh10 respectively for initial lead concentration of 3 mg/g. The effects of contact time showed that adsorption maximum was attained within 24h of contact time. The maximum adsorption capacity and removal efficiency were achieved at pH6. Small dose of adsorbent had better performance. The kinetics of adsorption was best described by the pseudo-second-Order model while the adsorption mechanism was chemisorption and pore diffusion based on intra-particle diffusion model. The isotherm model was Freundlich. Though, all tested isotherm models relatively showed good correlation coefficients ranging from 0.969-1.000. The adsorption process was exothermic for Azeh-TDI, with a negative value of -12.812 X 103 KJ/mol. This indicates that the adsorption process for Pb by Azeh-TDI was spontaneous. Adsorption by Azeh2 was endothermic in nature.

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Equilibrium and Kinetic Study of Lead and Copper Ion Adsorption on Chitosan-Grafted-Polyacrylic Acid Synthesized by Surface Initiated Atomic Transfer Polymerization

Molecules ◽

10.3390/molecules23092218 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2218 ◽

Cited By ~ 6

Author(s):

Carlos Grande-Tovar ◽

William Vallejo ◽

Fabio Zuluaga

Keyword(s):

Adsorption Capacity ◽

Polyacrylic Acid ◽

Adsorption Process ◽

Kinetic Constant ◽

Copper Ion ◽

Toxic Metal ◽

Maximum Adsorption Capacity ◽

Order Model ◽

Equilibrium Studies ◽

Pseudo Second Order

In this work, we synthesized chitosan grafted-polyacrylic acid (CS-g-PA) through surface-initiated atom transfer radical polymerization (SI-ATRP). We also studied the adsorption process of copper and lead ions onto the CS-g-PA surface. Adsorption equilibrium studies indicated that pH 4.0 was the best pH for the adsorption process and the maximum adsorption capacity over CS-g-PA for Pb2+ ions was 98 mg·g−1 and for Cu2+ it was 164 mg·g−1, while for chitosan alone (CS), the Pb2+ adsorption capacity was only 14.8 mg·g−1 and for Cu2+ it was 140 mg·g−1. Furthermore, the adsorption studies indicated that Langmuir model describes all the experimental data and besides, pseudo-second-order model was suitable to describe kinetic results for the adsorption process, demonstrating a larger kinetic constant of the process was larger for Pb2+ than Cu2+. Compared to other adsorbents reported, CS-g-PA had comparable or even superior adsorbent capacity and besides, all these results suggest that the new CS-g-PA polymers had potential as an adsorbent for hazardous and toxic metal ions produced by different industries.

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Efficient and Selective Adsorption of Gold Ions from Wastewater with Polyaniline Modified by Trimethyl Phosphate: Adsorption Mechanism and Application

Polymers ◽

10.3390/polym11040652 ◽

2019 ◽

Vol 11 (4) ◽

pp. 652 ◽

Cited By ~ 5

Author(s):

Wang ◽

Zhao ◽

Wang ◽

Zhang ◽

Zhang

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Selective Adsorption ◽

Interaction Mechanism ◽

Single Layer ◽

Phosphate Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Trimethyl Phosphate ◽

Selective Recovery

The selective recovery of gold from wastewater is necessary because it is widely used in various fields. In this study, a new polymeric adsorbent (TP-AFC) was prepared by modifying polyaniline with trimethyl phosphate for the selective recovery of gold from wastewater. Bath experiments were carried out to explore the adsorption capacity and mechanism. The optimum pH of adsorption is 4. The adsorption equilibrium is reached at 840 min. The maximum adsorption capacity is 881 mg/g and the adsorption was a spontaneous endothermic process. The adsorption process fitted well with pseudo second-order kinetic and the Langmuir-models. The single-layer chemisorption governed the adsorption process. In addition, the application in wastewater indicated that the interfering ions had no effect on the adsorption of gold ions. TP-AFC has good selectivity. The interaction mechanism was mainly ion exchange and complexation. In general, TP-AFC was successfully prepared and has an excellent future in practical application.

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STUDI ADSORPSI ZAT WARNA NAPHTHOL YELLOW S PADA LIMBAH CAIR MENGGUNAKAN KARBON AKTIF DARI AMPAS TEBU

Jurnal Kimia ◽

10.24843/jchem.2019.v13.i01.p16 ◽

2019 ◽

Vol 13 (1) ◽

pp. 104

Author(s):

W. P. Utoo1 ◽

E. Santoso ◽

G. Yuhaneka ◽

A. I. Triantini ◽

M. R. Fatqi ◽

...

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Surface Area ◽

Contact Time ◽

Adsorption Process ◽

Activation Process ◽

Adsorption Model ◽

High Adsorption ◽

Prolonged Contact ◽

Test Result

The aim of this research is to get activated carbon from sugarcane bagasse with high adsorption capacity to Naphthol Yellow S and to know factors influencing the adsorption capacity. Activated carbon is prepared by incomplete combustion of sugracane bagasse. The resulting carbon is activated with H2SO4 with concentration variation of 0.5; 1.0; 1.5 and 2.0 M and is continued by calcination at 400 °C. The measurement of the surface area of ??activated carbon by the methylene blue method indicates that the activation process successfully extends the surface area of carbon from 31.87 m2/g before activation to 66-72 m2/g after activation. Activated carbon with concentration of 2.0 M H2SO4 showed the highest surface area of ??71.85 m2/g, however, the best adsorption was shown by activated carbon with a concentration of 0.5 M H2SO4 with the adsorption capacity of 83.93%. The adsorption test showed that the best amount of adsorbent was 0.2 g with contact time for 30 minutes. Prolonged contact time can decrease the amount of Naphthol Yellow S adsorbed. The best adsorption test result was shown by sample with activator concentration of 0,5 M, mass of 0,2 g and contact time of 30 min with adsorption capacity 95,81% or amount of dye adsorbed equal to 143,72 mg/g. The adsorption study also showed that the entire Naphthol Yellow S adsorption process followed the Langmuir isothemal adsorption model. Qualitative testing of real batik waste indicates that activated carbon can reduce the dyes waste containing Naphthol Yellow Sexhibited by the color of batik waste which is more faded.

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Electrochemical Evaluation of Selenium (IV) Removal from Its Aqueous Solutions by Unmodified and Modified Graphene Oxide

Molecules ◽

10.3390/molecules24061063 ◽

2019 ◽

Vol 24 (6) ◽

pp. 1063

Author(s):

Zuzana Koudelkova ◽

Zuzana Bytesnikova ◽

Kledi Xhaxhiu ◽

Monika Kremplova ◽

David Hynek ◽

...

Keyword(s):

Graphene Oxide ◽

Iron Oxide ◽

Adsorption Capacity ◽

Selenium Concentration ◽

Stripping Voltammetry ◽

World Health ◽

Maximum Adsorption Capacity ◽

Adsorption Model ◽

Graphene Oxides ◽

Modified Graphene Oxide

The removal of selenium from superficial and waste water is a worldwide problem. The maximum limit according to the World Health Organization (WHO) for the selenium in the water is set at a concentration of 10 μg/L. Carbon based adsorbents have attracted much attention and recently demonstrated promising performance in removal of selenium. In this work, several materials (iron oxide based microparticles and graphene oxides materials) and their composites were prepared to remove Se(IV) from water. The graphene oxides were prepared according to the simplified Hummer’s method. In addition, the effect of pH, contact time and initial Se(IV) concentration was tested. An electrochemical method such as the differential pulse cathodic stripping voltammetry was used to determine the residual selenium concentration. From the experimental data, Langmuir adsorption model was used to calculate the maximum adsorption capacity. Graphene oxide particles modified by iron oxide based microparticles was the most promising material for the removal of Se(IV) from its aqueous solution at pH 2.0. Its adsorption efficiency reached more than 90% for a solution with given Se(IV) concentration, meanwhile its maximal recorded adsorption capacity was 18.69 mg/g.

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