Biochar of Spent Coffee Grounds as Per Se and Impregnated with TiO2: Promising Waste-Derived Adsorbents for Balofloxacin

Biochars (BC) of spent coffee grounds, both pristine (SCBC) and impregnated with titanium oxide (TiO2@SCBC) were exploited as environmentally friendly and economical sorbents for the fluroquinolone antibiotic balofloxacin (BALX). Surface morphology, functional moieties, and thermal stabilities of both adsorbents were scrutinized using SEM, EDS, TEM, BET, FTIR, Raman, and TG/dT analyses. BET analysis indicated that the impregnation with TiO2 has increased the surface area (50.54 m2/g) and decreased the pore size and volume. Batch adsorption experiments were completed in lights of the experimental set-up of Plackett-Burman design (PBD). Two responses were maximized; the % removal (%R) and the adsorption capacity (qe, mg/g) as a function of four variables: pH, adsorbent dosage (AD), BALX concentration ([BALX]), and contact time (CT). %R of 68.34% and 91.78% were accomplished using the pristine and TiO2@SCBC, respectively. Equilibrium isotherms indicated that Freundlich model was of a perfect fit for adsorption of BALX onto both adsorbents. Maximum adsorption capacity (qmax) of 142.55 mg/g for SCBC and 196.73 mg/g for the TiO2@SCBC. Kinetics of the adsorption process were best demonstrated using the pseudo-second order (PSO) model. The adsorption-desorption studies showed that both adsorbents could be restored with the adsorption efficiency being conserved up to 66.32% after the fifth cycles.

Download Full-text

Adsorption Characteristics of Pristine and Magnetic Olive Stones Biochar with Respect to Clofazimine

Nanomaterials ◽

10.3390/nano11040963 ◽

2021 ◽

Vol 11 (4) ◽

pp. 963

Author(s):

Marwa El-Azazy ◽

Iman Nabil ◽

Siham S. Hassan ◽

Ahmed S. El-Shafie

Keyword(s):

Cost Effective ◽

Sem Analysis ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Adsorption Efficiency ◽

Equilibrium Studies ◽

Thermal Stabilities ◽

Olive Stone ◽

Pseudo Second Order ◽

Adsorption Desorption

Olive stone biochars (OSBC), both pristine and following magnetization (MAG–OSBC), were utilized as eco-friendly and cost-effective sorbents for the antituberculosis, clofazimine (CLOF). Morphologies, textures, surface functionalities, and thermal stabilities of both adsorbents were explored using SEM, EDX, TEM, BET, FT-IR, Raman, XRD and TGA analyses. SEM analysis showed meso- and macroporous surfaces. BET data showed that the MAG–OSBC possesses a larger surface area (33.82 m2/g) and pore volume. Batch adsorption studies were conducted following the experimental scenario of Box–Behnken (BB) design. The adsorption efficiency of both adsorbents was evaluated in terms of the % removal (%R) and the sorption capacity (qe, mg/g). Dependent variables (%R and qe) were maximized as a function of four factors: pH, sorbent dose (AD), the concentration of CLOF ([CLOF]), and contact time (CT). A %R of 98.10% and 98.61% could be obtained using OSBC and MAG–OSBC, respectively. Equilibrium studies indicated that both Langmuir and Freundlich models were perfectly fit for adsorption of CLOF. Maximum adsorption capacity (qmax) of 174.03 mg/g was obtained using MAG–OSBC. Adsorption kinetics could be best illustrated using the pseudo-second-order (PSO) model. The adsorption–desorption studies showed that both adsorbents could be restored with the adsorption efficiency being conserved up to 92% after the sixth cycles.

Download Full-text

Calcium PretreatedHevea brasiliensisSawdust for Copper Removal: Batch and Column Study

Journal of Chemistry ◽

10.1155/2015/495257 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9

Author(s):

Swarup Biswas ◽

Umesh Mishra

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Copper Ion ◽

Packed Bed ◽

Isotherm Models ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Packed Bed Column ◽

Pseudo Second Order ◽

Kinetics Of

Calcium pretreatedHevea brasiliensissawdust has been used as an effective and efficient adsorbent for the removal of copper ion from the contaminated water. Batch experiment was conducted to check the effect of pH, initial concentration, contact time, and adsorbent dose. The results conclude that adsorption capacity of adsorbent was influenced by operating parameters. Maximum adsorption capacity found from the batch adsorption process was 37.74 mg/g at pH of 5.6. Various isotherm models like Langmuir, Freundlich, and Temkin were used to compare the theoretical and experimental data, whereas the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were applied to study the kinetics of the batch adsorption process. Dynamic studies were also conducted in packed-bed column using different bed depths and the maximum adsorption capacity of 34.29 was achieved. Characterizations of the adsorbent were done by Fourier transform infrared spectroscopy, scanning electron microscope, and energy dispersive X-ray spectroscopy.

Download Full-text

Removal of Mercury(II) from Aqueous Solutions by Adsorption on Poly(1-amino-5-chloroanthraquinone) Nanofibrils: Equilibrium, Kinetics, and Mechanism Studies

Journal of Nanomaterials ◽

10.1155/2016/7245829 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 13

Author(s):

Shaojun Huang ◽

Chengzhang Ma ◽

Yaozu Liao ◽

Chungang Min ◽

Ping Du ◽

...

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Batch Adsorption ◽

Pseudo Second Order ◽

Ft Ir ◽

Repeated Use ◽

Real Wastewater ◽

Adsorption Desorption ◽

Order Rate Equation

Poly(1-amino-5-chloroanthraquinone) (PACA) nanofibrils were applied as novel nanoadsorbents for highly toxic mercury removal from aqueous solutions. A series of batch adsorption experiments were conducted to study the effect of adsorbent dose, pH, contact time, and metal concentration on Hg(II) uptake by PACA nanofibrils. Kinetic data indicated that the adsorption process of PACA nanofibrils for Hg(II) achieved equilibrium within 2 h following a pseudo-second-order rate equation. The adsorption mechanism of PACA nanofibrils for Hg(II) was investigated by Fourier transform-infrared (FT-IR) spectra and X-ray photoelectron spectroscopy (XPS) analyses. The adsorption isotherm of Hg(II) fitted well the Langmuir model, exhibiting superb adsorption capacity of 3.846 mmol of metal per gram of adsorbent. Lastly, we found out that the as-synthesized PACA nanofibrils are efficient in Hg(II) removal from real wastewater. Furthermore, five consecutive adsorption-desorption cycles demonstrated that the PACA nanofibrils were suitable for repeated use without considerable changes in the adsorption capacity.

Download Full-text

A Novel Geopolymer Foam Based On ZSM-5 Zeolite Fabricated Using Templating Emulsion/Chemical Foaming Method and Its Application in Batch and Continuous Dye Removal Systems

10.21203/rs.3.rs-1227901/v1 ◽

2022 ◽

Author(s):

Mahboobeh Monjezi ◽

Vahid Javanbakht

Keyword(s):

Adsorption Capacity ◽

Dye Removal ◽

Adsorption Process ◽

Dye Adsorption ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Continuous Systems ◽

Green Materials ◽

Pseudo Second Order ◽

Chemical Foaming

Abstract Geopolymers as sustainable and environmentally friendly “green materials”, can be synthesized by utilizing waste material and by-products. A porous geopolymer foam adsorbent based on ZSM-5 zeolite was prepared using templating emulsion/chemical foaming method in different conditions and used for dye removal in batch and continuous systems. The parameters affecting the dye adsorption including temperature, concentration, and pH, kinetics, isotherm, and thermodynamics of the process were investigated. The results of the geopolymer foam synthesis showed that thermal pretreatment of the zeolite has a positive effect on the strength and adsorption capacity. Moreover, the increase in sodium silicate more than the stoichiometric reduces the strength and adsorption capacity. The findings obtained from the batch adsorption process showed that the adsorption kinetics of the pseudo-second-order model and the adsorption isotherm of the Temkin model is adjusted with the experimental data. Thermodynamic results indicated that the process of dye adsorption with geopolymer foam is exothermic. The results from continuous experiments indicated more compatibility of the adsorption process with the models of Thomas and Bohart-Adams. The maximum adsorption capacity of methylene blue in batch and continuous processes was 9.82 and 8.17 mg/g. The adsorbent reduction was performed successfully by chemical and thermal processes.

Download Full-text

Synthesis of magnetic biochar derived from cotton stalks for the removal of Cr(VI) from aqueous solution

Water Science & Technology ◽

10.2166/wst.2019.208 ◽

2019 ◽

Vol 79 (11) ◽

pp. 2106-2115 ◽

Cited By ~ 3

Author(s):

Fengfeng Ma ◽

Baowei Zhao ◽

Jingru Diao

Keyword(s):

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Cotton Stalk ◽

Magnetic Biochar ◽

X Ray ◽

Cotton Stalks ◽

Pseudo Second Order ◽

Co Precipitation

Abstract A magnetic cotton stalk biochar (MCSBC) was synthesized through chemical co-precipitation, based on cotton stalk biochar (CSBC). The MCSBC and CSBC were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and vibrating sample magnetometry. The characterization analyses showed that the magnetization process endowed the CSBC with excellent magnetic properties with a superparamagnetic magnetization of 27.59 emu/g. Batch adsorption experiment results indicated that the Cr(VI) maximum adsorption capacity of MCSBC was 20.05 mg/g, which was higher than that of CSBC (18.77 mg/g). The adsorption kinetic data were well fitted by the pseudo-second-order model and the adsorption isotherms were well represented by the Sips isotherm model. The thermodynamic studies indicated that the adsorption process was spontaneous and endothermic, and the entropy increased. The potential adsorption mechanism was the electrostatic adsorption of anionic Cr(VI) to the positively charged MCSBC surface, the reduction of Cr(VI) into Cr(III) and the complexation of Cr(III) by oxygen-containing functional groups of MCSBC. The regeneration studies showed that MCSBC kept 80% of its initial Cr(VI) adsorption capacity in the cycle. All the findings suggest that this novel magnetic biochar could be used in the field of Cr(VI)-containing wastewater treatment.

Download Full-text

Development of Natural Cation Exchanger for the Treatment of Lead ions from Aqueous Solution

Journal of Nepal Chemical Society ◽

10.3126/jncs.v29i0.9235 ◽

2013 ◽

Vol 29 ◽

pp. 34-43

Author(s):

Puspa Lal Homagai

Keyword(s):

Adsorption Capacity ◽

Sugarcane Bagasse ◽

Active Sites ◽

Freundlich Isotherm ◽

Saccharum Officinarum ◽

Isotherm Models ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Fast Kinetics ◽

Pseudo Second Order

Cellulose, hemicelluloses and lignin are the main constituents found in sugarcane (Saccharum officinarum) bagasse having many surface active sites containing hydroxyl and/or phenolic groups which are effective for chemical modification. The biowaste was first charred with concentrated sulphuric acid and then the charred aminated sugarcane bagasse (CASB) was prepared by reduction followed by oxidation. The developed bio-sorbent was characterized by SEM, TGA/DTA, FTIR and elemental analysis. Batch adsorption methods were carried out to determine Pb+2 sorption capacities at different pH ranges and sorbate concentrations. The maximum adsorption capacity for Pb+2 was found to be 323 mg g-1 with an efficiency of 98% at pH 4.The experimental data showed a good fit to Langmuir isotherm as compared to Freundlich isotherm models. The kinetics was best fitted with the pseudo-second order model. The adsorption equilibrium was attained within 20 min. The high adsorption capacity and fast kinetics results of the charred aminated sugarcane bagasse indicated that it might be potential adsorbent for the removal of lead from contaminated water. DOI: http://dx.doi.org/10.3126/jncs.v29i0.9235Journal of Nepal Chemical SocietyVol. 29, 2012Page: 34-43Uploaded date : 12/3/2013

Download Full-text

Equilibrium, Kinetic, and Thermodynamic Studies on the Adsorption of Cadmium from Aqueous Solution by Modified Biomass Ash

Bioinorganic Chemistry and Applications ◽

10.1155/2017/3695604 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 13

Author(s):

Lei Xu ◽

Xuebo Zheng ◽

Hongbiao Cui ◽

Zhenqiu Zhu ◽

Jiani Liang ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Metal Concentration ◽

Morphological Properties ◽

Maximum Adsorption Capacity ◽

Icp Oes ◽

Biomass Ash ◽

Bet Analysis ◽

Pseudo Second Order ◽

Kinetic And Thermodynamic Studies

Natural biomass ash of agricultural residuals was collected from a power plant and modified with hexagonal mesoporous silica and functionalized with 3-aminopropyltriethoxysilane. The physicochemical and morphological properties of the biomass ash were analyzed by ICP-OES, SEM, TEM-EDS, FTIR, and BET analysis. The adsorption behavior of the modified product for Cd2+ in aqueous solution was studied as a function of pH, initial metal concentration, equilibrium time, and temperature. Results showed that the specific surface area of the modified product was 9 times that of the natural biomass ash. The modified biomass ash exhibited high affinity for Cd2+ and its adsorption capacity increased sharply with increasing pH from 4.0 to 6.0. The maximum adsorption capacity was 23.95 mg/g in a pH 5 solution with an initial metal concentration of 50 mg/L and a contact time of 90 min. The adsorption of Cd2+ onto the modified biomass ash was well fitted to the Langmuir model and it followed pseudo-second-order kinetics. Thermodynamic analysis results showed that the adsorption of Cd2+ was spontaneous and endothermic in nature. The results suggest that the modified biomass ash is promising for use as an inexpensive and effective adsorbent for Cd2+ removal from aqueous solution.

Download Full-text

Selective and rapid removal of Mo(VI) from water using functionalized Fe3O4-based Mo(VI) ion-imprinted polymer

Water Science & Technology ◽

10.2166/wst.2020.594 ◽

2020 ◽

Author(s):

Lang Wu ◽

Zhengwei Luo ◽

Hui Jiang ◽

Zijian Zhao ◽

Wenhua Geng

Keyword(s):

Adsorption Capacity ◽

Isotherm Model ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Ion Imprinted Polymer ◽

Imprinted Polymer ◽

Adsorption Selectivity ◽

X Ray ◽

Ion Imprinted ◽

Adsorption Desorption

Abstract Fe3O4 nanoparticles-based magnetic Mo(VI) surface ion-imprinted polymer (Mo(VI)-MIIP) was elaborated employing 4-vinyl pyridine as a functional monomer. The adsorbent preparation was confirmed by Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, vibrating sample magnetometer, thermogravimetric analysis, and surface area analysis. Batch adsorption experiments displayed that the maximum adsorption capacity of Mo(VI)-MIIP was 296.40 mg g−1 at pH 3, while that of the magnetic non-imprinted polymer (MNIP) was only 147.10 mg g−1. The adsorption isotherm model was well-fitted by the Langmuir isotherm model. The adsorption experiments revealed that Mo(VI)-MIIP reached adsorption equilibrium within 30 min, and the kinetics data fitting showed that the pseudo-second-order kinetics model suitably described the adsorption process. Mo(VI)-MIIP exhibited an excellent adsorption selectivity to Mo(VI) in binary mixtures of Mo(VI)/Cr(VI), Mo(VI)/Cu(II), Mo(VI)/H2PO44-, Mo(VI)/Zn(II), and Mo(VI)/I–, with relative selectivity coefficients toward MNIP of 13.71, 30.27, 20.01, 23.53, and 15.89, respectively. After six consecutive adsorption-desorption cycles, the adsorption capacity of Mo(VI)-MIIP decreased by 9.5% (from 228.4 mg g−1 to 206.7 mg g−1 at initial Mo(VI) concentration of 250 mg L−1), demonstrating its reusability.

Download Full-text

Poly(amidoamine) dendrimer modified superparamagnetic nanoparticles as an efficient adsorbent for Cr(VI) removal: Effect of high-generation dendrimer on adsorption performance

10.21203/rs.3.rs-890076/v1 ◽

2021 ◽

Author(s):

Can Cui ◽

Yadian Xie ◽

Jiaojiao Niu ◽

Hailiang Hu ◽

Sen Lin

Keyword(s):

Adsorption Capacity ◽

Pamam Dendrimer ◽

Superparamagnetic Nanoparticles ◽

Batch Adsorption ◽

Adsorption Model ◽

Langmuir Adsorption ◽

Pseudo Second Order ◽

Modified Adsorbents ◽

Adsorption Desorption ◽

Efficient Adsorbent

Abstract Heavy metal ions pollution is one of the most dangerous and critical threats to human health and environment. In this work, three different generations of PAMAM dendrimer decorated on magnetic Fe 3 O 4 composites (Fe 3 O 4 @SiO 2 –G1, Fe 3 O 4 @SiO 2 –G3, Fe 3 O 4 @SiO 2 –G5) were fabricated and characterized by FTIR, XRD, TEM, and TGA. The obtained composites were used for Cr(VI) removal. Batch adsorption studies showed that the adsorption reached equilibrium within 60 min, and the optimal pH was 3.0. The result of adsorption kinetics was simulated by the pseudo–second-order model. The adsorption equilibrium isotherm was well fitted with the Langmuir adsorption model. Furthermore, thermodynamics calculations revealed that the adsorption process was endothermic and spontaneous. Importantly, adsorption capacity of Cr(VI) obey the sequence of Fe 3 O 4 @SiO 2 –G1＜Fe 3 O 4 @SiO 2 –G5＜Fe 3 O 4 @SiO 2 –G3, 3 generation of PAMAM (3G) is the optimal for adsorption capacity of Cr(VI). The maximum theoretical Cr(VI) adsorption capacity ( q m ) of Fe 3 O 4 @SiO 2 –G3 was 334.45 mg/g, and removal ration remained above 89.5% after five cycles of adsorption–desorption. Thus, Fe 3 O 4 @SiO 2 –G3 is predicted to be an efficient adsorbent for the adsorption of Cr(VI) from aqueous solution, and the obtained results can help in the generation optimization during fabrication of dendrimer modified adsorbents.

Download Full-text

Preparation of Polyaniline/Emulsion Microsphere Composite for Efficient Adsorption of Organic Dyes

Polymers ◽

10.3390/polym12010167 ◽

2020 ◽

Vol 12 (1) ◽

pp. 167 ◽

Cited By ~ 6

Author(s):

Yuanli Liu ◽

Liushuo Song ◽

Linlin Du ◽

Peng Gao ◽

Nuo Liang ◽

...

Keyword(s):

Adsorption Capacity ◽

In Situ Polymerization ◽

Organic Dyes ◽

Removal Rate ◽

Three Dimensional ◽

Maximum Adsorption Capacity ◽

Adsorption Selectivity ◽

Polymeric Microspheres ◽

Pseudo Second Order ◽

Adsorption Desorption

Surface-functionalized polymeric microspheres have wide applications in various areas. Herein, monodisperse poly(styrene–methyl methacrylate–acrylic acid) (PSMA) microspheres were prepared via emulsion polymerization. Polyaniline (PANI) was then coated on the PSMA surface via in situ polymerization, and a three-dimensional (3D) structured reticulate PANI/PSMA composite was, thus, obtained. The adsorption performance of the composite for organic dyes under different circumstances and the adsorption mechanism were studied. The obtained PANI/PSMA composite exhibited a high adsorption rate and adsorption capacity, as well as good adsorption selectivity toward methyl orange (MO). The adsorption process followed pseudo-second-order kinetics and the Langmuir isotherm. The maximum adsorption capacity for MO was 147.93 mg/g. After five cycles of adsorption–desorption, the removal rate remained higher than 90%, which indicated that the adsorbent has great recyclability. The adsorbent materials presented herein would be highly valuable for the removal of organic dyes from wastewater.

Download Full-text