Super Absorbent Polymers in Environmental Remediation

Laboratory studies reported earlier, have shown very promising results in the selective removal of dyes from aqueous solutions by a commercially available (super absorbent polymer) SAP, Jalshakti® (JS). JS is mesoporous in nature and is a potential adsorbent for the basic dyes studied. This paper presents the adsorption and kinetic studies for the Methylene blue dye (MB) in a batch mode. The equilibrium adsorption capacity increases from 138.9 to 1428.6 mgg-1 as the initial concentration of MB increases from 100-1000 mg l-1. The maximum adsorption capacity obtained is 1200 mgg-1 which is more than the adsorbents reported in literature. The Kf value is 165.3 mg1-(1/n)g-1L1/n. The slope 1/n, ranging between 0 and 1, is indicative of the relative energy distribution on the adsorbent surface (or surface heterogeneity) The kinetics of the adsorption process suggests that the pseudo second order model is predominant. The pore diffusion kinetics as described by intraparticle diffusion model also controls the adsorption process but is not the only rate limiting mechanism.

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Study of Kinetics and Adsorption Isotherm of Methylene Blue Dye using Tannin Gel from Ceriops tagal

Jurnal Kimia Sains dan Aplikasi ◽

10.14710/jksa.23.10.370-376 ◽

2020 ◽

Vol 23 (10) ◽

pp. 370-376

Author(s):

Thamrin Azis ◽

La Ode Ahmad ◽

Keke Awaliyah ◽

Laode Abdul Kadir

Keyword(s):

Methylene Blue ◽

Adsorption Capacity ◽

Adsorption Kinetics ◽

Contact Time ◽

Adsorption Process ◽

Blue Dye ◽

Maximum Adsorption Capacity ◽

Methylene Blue Dye ◽

Ceriops Tagal ◽

Kinetics Of

Research on the equilibrium and adsorption kinetics of methylene blue dye using tannin gel from the Tingi tree (Ceriops tagal) has been carried out. This study aims to determine the capacity and adsorption kinetics of tannin gel against methylene blue dye. Several parameters, such as the effect of contact time, pH, and methylene blue dye concentration on adsorption, were also studied. Based on the research results, the optimum adsorption process is a contact time of 30 minutes and a pH of 7. The adsorption capacity increased to a concentration of 80 mg/L with a maximum adsorption capacity (qm) of 49.261 mg/g. The adsorption process follows the pseudo-second-order adsorption kinetics model and the Langmuir isotherm model.

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Influence of phosphorus and nitrogen co-doping of activated carbon from littered cigarette filters for adsorption of methylene blue dye from wastewater

Sustainable Environment Research ◽

10.1186/s42834-021-00108-5 ◽

2021 ◽

Vol 31 (1) ◽

Author(s):

Samantha Macchi ◽

Zane Alsebai ◽

Fumiya Watanabe ◽

Arooba Ilyas ◽

Shiraz Atif ◽

...

Keyword(s):

Water Pollution ◽

Adsorption Capacity ◽

Adsorption Process ◽

Surface Characteristics ◽

Point Of Zero Charge ◽

Blue Dye ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Textile Dye ◽

Co Doping

AbstractGlobal access to sanitary water is of utmost importance to human health. Presently, textile dye water pollution and cigarette pollution are both plaguing the environment. Herein, waste cigarette filters (CFs) are converted into useful carbon-based adsorbent materials via a facile, microwave-assisted carbonization procedure. The CFs are activated and co-doped with phosphorus and nitrogen simultaneously to enhance their surface characteristics and adsorbent capability by introducing chemisorptive binding sites to the surface. The doped carbonized CF (DCCF) and undoped carbonized CF (CCF) adsorbents are characterized physically to examine their surface area, elemental composition, and surface charge properties. The maximum adsorption capacity of synthesized adsorbents was determined via batch adsorption experiments and Langmuir modelling. Additionally, the influence of different parameters on the adsorption process was studied by varying the adsorption conditions such as adsorbent dosage, initial concentration, contact time, temperature, and pH. The DCCF adsorbent showed a maximum adsorption capacity of 303 mg g− 1. Adsorption of both adsorbents fit best to Langmuir model and pseudo-second order kinetics, indicating chemisorptive mechanism. Both adsorbents showed endothermic adsorption process which is indicated by increasing adsorption capacity with increased temperatures. DCCF exhibited greater adsorption capability than CCF at all temperatures from 25 to 55 °C. The pH of the solution significantly affected the adsorption capacity of CCF while DCCF adsorption is favorable at a wide pH range due to low value of the adsorbent’s point of zero charge. Reusability results showed that both adsorbents can be used over several cycles for removal of dye. Thus, results conclude that the waste DCCF-based adsorbent does not only show a profound potential as a sustainable solution to combat textile dye water pollution but also addresses the valuable use of the CF pollution simultaneously. This approach, which can target two major pollutants, is attractive due to its ease of preparation, negligible cost, and versatility in application.

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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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Kinetic Studies of Cs+ and Sr2+ Ion Exchange Using Clinoptilolite in Static Columns and an Agitated Tubular Reactor (ATR)

ChemEngineering ◽

10.3390/chemengineering5010009 ◽

2021 ◽

Vol 5 (1) ◽

pp. 9

Author(s):

Muhammad Yusuf Prajitno ◽

Mohamad Taufiqurrakhman ◽

David Harbottle ◽

Timothy N. Hunter

Keyword(s):

Adsorption Capacity ◽

Tubular Reactor ◽

Process Intensification ◽

Kinetic Studies ◽

Breakthrough Curves ◽

Maximum Adsorption Capacity ◽

Batch Studies ◽

Shear Mixing ◽

Natural Clinoptilolite ◽

Kinetics Of

Natural clinoptilolite was studied to assess its performance in removing caesium and strontium ions, using both static columns and an agitated tube reactor (ATR) for process intensification. Kinetic breakthrough curves were fitted using the Thomas and Modified Dose Response (MDR) models. In the static columns, the clinoptilolite adsorption capacity (qe) for 200 ppm ion concentrations was found to be ~171 and 16 mg/g for caesium and strontium, respectively, highlighting the poor material ability to exchange strontium. Reducing the concentration of strontium to 100 ppm, however, led to a higher strontium qe of ~48 mg/g (close to the maximum adsorption capacity). Conversely, halving the column residence time to 15 min decreased the qe for 100 ppm strontium solutions to 13–14 mg/g. All the kinetic breakthrough data correlated well with the maximum adsorption capacities found in previous batch studies, where, in particular, the influence of concentration on the slow uptake kinetics of strontium was evidenced. For the ATR studies, two column lengths were investigated (of 25 and 34 cm) with the clinoptilolite embedded directly into the agitator bar. The 34 cm-length system significantly outperformed the static vertical columns, where the adsorption capacity and breakthrough time were enhanced by ~30%, which was assumed to be due to the heightened kinetics from shear mixing. Critically, the increase in performance was achieved with a relative process flow rate over twice that of the static columns.

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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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Adsorption Study of Cu2+ Ions from Aqueous Solutions by Bael Flowers (Aegle marmelos)

Biointerface Research in Applied Chemistry ◽

10.33263/briac114.1189111904 ◽

2020 ◽

Vol 11 (4) ◽

pp. 11891-11904

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Metal Ion ◽

Low Cost ◽

Sem Analysis ◽

Ion Concentration ◽

Maximum Adsorption Capacity ◽

Aegle Marmelos ◽

Batch Mode ◽

Initial Ph

In the present study, batch mode adsorption was carried out to investigate the adsorption capacity of dried bael flowers (Aegle marmelos) for the adsorptive removal of Cu(II) ions from aqueous solutions by varying agitation time, initial metal concentration, the dose of adsorbent, temperature, and initial pH of the Cu(II) ion solution. The percentage removal of 98.7% was observed at 50 ppm initial metal ion concentration, 0.5 g/100.00 cm3 adsorbent dosage, within the contact time of 120 minutes at 30 ºC in the pH range of 4 – 7. The sorption processes of Cu(II) ions was best described by pseudo-second-order kinetics. Langmuir isotherm had a good fit with the experimental data with 0.97 of correlation coefficient (R2), and the maximum adsorption capacity obtained was 23.14 mg g-1 at 30 ºC. The results obtained from sorption thermodynamic studies suggested that the adsorption process is exothermic and spontaneous. SEM analysis showed tubular voids on the adsorbent. FTIR studies indicated the presence of functional groups like hydroxyl, –C-O, –C=O, and amide groups in the adsorbent, which can probably involve in metal ion adsorption. Therefore, dried bael flowers can be considered an effective low-cost adsorbent for treating Cu(II) ions.

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Karekterisasi, Kinetika, dan Isoterm Adsorpsi Limbah Ampas Kelapa sebagai Adsorben Ion Cu(II)

SAINTIFIK ◽

10.31605/saintifik.v6i2.265 ◽

2020 ◽

Vol 6 (2) ◽

pp. 104-115

Author(s):

Agusriyadin Agusriyadin

Keyword(s):

Adsorption Capacity ◽

Ph Effect ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Optimum Conditions ◽

Langmuir Adsorption ◽

Adsorbent Surface ◽

Adsorption Data ◽

Order Kinetic Model ◽

Pseudo Second Order

Penelitian ini bertujuan untuk menguji kemampuan AK dan AKPM dalam mengadsorpsi ion Cu (II), pengaruh parameter adsorpsi dan mekanisme adsorpsi. AK dan AKP Madsorben dibuat dari residu ampas kelapa. Adsorben dikarakterisasi dengan FTIR, SEM dan EDS. Pengaruh parameter adsorpsi seperti pH awal, dosis adsorben, waktu kontak dan konsentrasi ion Cu (II) awal diperiksa untuk menentukan kondisi optimum serapan tembaga (II). Ion Cu (II) yang teradsorpsi diukur berdasarkan pada konsentrasi Ion Cu (II) sebelum dan sesudah adsorpsi menggunakan metode AAS. Hasil karakterisasi menunjukkan bahwa struktur pori dan gugus fungsi tersedia pada permukaan adsorben. Menurut percobaan efek pH, kapasitas adsorpsi maksimum dicapai pada pH 7. Waktu kontak optimal dan konsentrasi tembaga awal (II) ditemukan masing-masing pada 120 menit dan 100 mg L-1. Data eksperimental sesuai dengan model kinetik orde dua orde dua, dan Langmuir isoterm adsorpsi yang diperoleh paling sesuai dengan data adsorpsi. Kapasitas adsorpsi maksimum adsorben ditemukan menjadi 4,73 dan 6,46 mg g-1 pada kondisi optimal. The results of characterization showed that the pore structure and the functional groups were available on adsorbent surface. According to the pH effect experiments, the maximum adsorption capacity was achieved at pH 7. Optimum contact time and initial copper(II) concentration were found at 120 min and 100 mg L-1, respectively. The experimental data were comply with the pseudo-second-order kinetic model, and Langmuir adsorption isotherm obtained best fitted the adsorption data. The maximum adsorption capacity of the adsorbents was found to be 4.73 and 6.46 mg g-1 at optimum conditions.

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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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