Adsorption of Acid Blue 25 on Agricultural Wastes: Efficiency, Kinetics, Mechanism, and Regeneration

In this study, Acid Blue 25 (AB25), which is a negatively charged synthetic dye was removed from an aqueous solution by adsorption onto agricultural wastes, including banana (BP) and durian (DP) peels. The adsorption performances of AB25 were related to surface characteristics of the agricultural wastes, including their chemical functional groups, net surface charge, surface morphology, surface area, and pore volume. Parameters affecting the adsorption, including contact times, initial concentration, pH, and temperature were investigated. The results revealed that the adsorption of AB25 followed pseudo-second order kinetics, and that the adsorption process was controlled by a combination of intraparticle and film diffusion with a two-step mechanism. The equilibrium data could be simulated by the Langmuir isotherm model, suggesting that AB25 molecules are adsorbed on active sites with a uniform binding energy as a monolayer on the adsorbent surface. The adsorption process was spontaneous and exothermic, and the adsorption capacity decreased with the pH of the medium. The spent adsorbents were best regenerated by acid treatment (pH 2), and could be recycled for several adsorption-desorption processes. Under ambient conditions, the maximum adsorption capacities of AB25 on BP and DP were 70.0 and 89.7 mg g−1, respectively, which is much higher than on a large variety of reported adsorbents derived from other agricultural wastes.

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Surface properties and adsorption characteristics to methylene blue and iodine of adsorbents from sludge

Water Science & Technology ◽

10.2166/wst.2010.372 ◽

2010 ◽

Vol 62 (8) ◽

pp. 1705-1712 ◽

Cited By ~ 9

Author(s):

L. Y. Deng ◽

G. R. Xu ◽

G. B. Li

Keyword(s):

Methylene Blue ◽

Electrostatic Interactions ◽

Active Sites ◽

Pyrolysis Temperature ◽

Weight Ratio ◽

Surface Characteristics ◽

Wastewater Sludge ◽

X Ray ◽

Adsorption Characteristics ◽

Adsorbent Surface

Adsorbent materials created from wastewater sludge have unique surface characteristics and could be effective in adsorption applications. In this research, the sludge-adsorbents were generated by pyrolyzing mixtures of sewage sludge and H2SO4. Scanning electron microscope (SEM), thermal analysis, X-ray diffraction (XRD) and X-ray photoelectron spectroscope (XPS) were used to analyze the properties of sludge-adsorbent. XPS results show that the adsorbent surface functional groups with high contents of oxygen-containing groups serve as active sites for the adsorption and affect the surface characteristics; the adsorption mechanism of methylene blue (MB) is mainly Brönsted acid-base reaction between the adsorbent surface and MB; and iodine atoms are bonded to the surface of the adsorbent mainly by dispersive interactions rather than by electrostatic interactions. The results also show that H2SO4 level, pyrolysis temperature and sulfuric acid/sludge weight ratio actually affected the adsorption characteristics. Using the conditions (H2SO4 level of 1–18 M, pyrolysis temperature of 650°C, and weight ratio of 0.8), the adsorption capacities for MB and iodine were 74.7–62.3 mg g−1 and 169.5–209.3 mg g−1, respectively.

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A Biodegradable Magnetic Nanocomposite as a Superabsorbent for the Simultaneous Removal of Selected Fluoroquinolones from Environmental Water Matrices: Isotherm, Kinetics, Thermodynamic Studies and Cost Analysis

Polymers ◽

10.3390/polym12051102 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1102 ◽

Cited By ~ 4

Author(s):

Geaneth Pertunia Mashile ◽

Kgokgobi Mogolodi Dimpe ◽

Philiswa Nosizo Nomngongo

Keyword(s):

Correlation Coefficients ◽

Surface Characteristics ◽

Environmental Water ◽

Magnetic Nanocomposite ◽

Bet Surface Area ◽

X Ray Diffraction ◽

Thermodynamic Studies ◽

Equilibrium Data ◽

Environmental Water Matrices ◽

Adsorption Desorption

The application of a magnetic mesoporous carbon/β-cyclodextrin–chitosan (MMPC/Cyc-Chit) nanocomposite for the adsorptive removal of danofloxacin (DANO), enrofloxacin (ENRO) and levofloxacin (LEVO) from aqueous and environmental samples is reported in this study. The morphology and surface characteristics of the magnetic nanocomposite were investigated by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption–desorption and Fourier transform infrared spectroscopy (FTIR). The N2 adsorption–desorption results revealed that the prepared nanocomposite was mesoporous and the BET surface area was 1435 m2 g−1. The equilibrium data for adsorption isotherms were analyzed using two and three isotherm parameters. Based on the correlation coefficients (R2), the Langmuir and Sips isotherm described the data better than others. The maximum monolayer adsorption capacities of MMPC/Cyc-Chit nanocomposite for DANO, ENRO and LEVO were 130, 195 and 165 mg g−1, respectively. Adsorption thermodynamic studies performed proved that the adsorption process was endothermic and was dominated by chemisorption.

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Adsorption of crystal violet with diatomite earth&carbon by a modification of hydrothermal carbonization process

Water Science & Technology ◽

10.2166/wst.2015.625 ◽

2015 ◽

Vol 73 (6) ◽

pp. 1463-1471 ◽

Cited By ~ 1

Author(s):

Zhang Yanzhuo ◽

Li Jun ◽

Chen Guanghui ◽

Bian Wei ◽

Lu Yun ◽

...

Keyword(s):

Crystal Violet ◽

Adsorption Process ◽

Hydrothermal Carbonization ◽

Dyeing Wastewater ◽

Order Model ◽

Average Pore ◽

Printing And Dyeing Wastewater ◽

Equilibrium Data ◽

Pseudo Second Order ◽

Adsorption Desorption

The high colority and difficulty of decolorization are the most important tasks on printing and dyeing wastewater. This study investigates the ability of diatomite earth&carbon (DE&C) as an adsorbent to removal crystal violet (CV) from aqueous solutions. Fourier transform infrared spectroscopy results indicate the importance of functional groups during the adsorption of CV. The obtained N2 adsorption–desorption isotherm values accord with well IUPAC type II. Our calculations determined a surface area of 73.15 m2 g−1 for DE&C and an average pore diameter of 10.56 nm. Equilibrium data of the adsorption process fitted very well to the Langmuir model (R2 > 0.99). The results of kinetics study showed that the pseudo-second-order model fitted to the experimental data well. The thermodynamic parameters were also evaluated. ΔH° <0, ΔS° > 0 and ΔG° < 0 demonstrated that the adsorption process was spontaneous and exothermic for dye. Furthermore the positive value of ΔS° reflected good affinity of the CV dye.

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Adsorption behavior of phosphate on anion-functionalized nanoporous polymer

Water Quality Research Journal ◽

10.2166/wqrj.2017.008 ◽

2015 ◽

Vol 52 (3) ◽

pp. 187-195 ◽

Cited By ~ 3

Author(s):

Zhenyu Wu ◽

Dasheng Gao ◽

Ningning Liu

Keyword(s):

Adsorption Process ◽

Treatment Method ◽

Langmuir Model ◽

Adsorption Behavior ◽

Maximum Adsorption Capacity ◽

Order Model ◽

N2 Adsorption ◽

Equilibrium Data ◽

Pseudo Second Order ◽

Adsorption Desorption

An anion-functionalized nanoporous polymer was successfully prepared by quaternary ammonization and anion-exchange treatment method. The polymer was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, N2 adsorption/desorption isotherms and thermogravimetric analysis. Batch experiments were conducted to investigate the adsorption behavior of phosphate on the polymer. The results indicated that the experimental equilibrium data can be well described by the Langmuir model. The maximum adsorption capacity determined from the Langmuir model was 4.92 mg g−1. For kinetic study, the adsorption behavior followed the pseudo-second-order model. Thermodynamic studies indicated that the adsorption process was spontaneous and exothermic.

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Isotherm, Kinetic and Thermodynamic Studies on Adsorption of Bromocresol Purple, Acid Red 66 and Acid Blue 40 Using Activated Carbon

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19176 ◽

2021 ◽

Vol 21 (7) ◽

pp. 4104-4109

Author(s):

Jong Jib Lee ◽

Jong Ki Jeon

Keyword(s):

Activated Carbon ◽

Adsorption Process ◽

Adsorption Equilibrium ◽

Physical Adsorption ◽

Isotherm Models ◽

Bromocresol Purple ◽

Kinetic And Thermodynamic Parameters ◽

Equilibrium Data ◽

Adsorption Equilibrium Data ◽

Acid Blue

This study was conducted with a batch reaction to equilibrium isotherm, kinetic and thermodynamic parameters on adsorption of bromocresol purple (BCP), acid red 66 (AR 66) and acid blue 40 (AB 40) from aqueous solution by using activated carbon with nanopores. Freundlich and Temkin isotherm models were used to evaluate the suitability of isotherm for adsorption equilibrium data. The adsorption equilibrium was best fitted by Temkin model. The Freundlich separation factor values indicated that adsorption on the nanoporous activated carbon could effectively treat three dyes. The kinetic analysis of the adsorption process confirmed that it was more consistent with the pseudo second order model. The intraparticle diffusion was rate limiting step. The adsorption process of three dyes were endothermic because they were positive enthalpy values. The free energy values of three dyes decreased with increasing temperature, so that the spontaneity becomes higher with temperature increase. The activation energy value of three dyes were confirmed the physical adsorption.

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Simultaneous Removal of Pb2+ and Zn2+ Heavy Metals Using Fly Ash Na-X Zeolite and its Carbon Na-X(C) Composite

Materials ◽

10.3390/ma14112832 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2832

Author(s):

Rafał Panek ◽

Magdalena Medykowska ◽

Małgorzata Wiśniewska ◽

Katarzyna Szewczuk-Karpisz ◽

Katarzyna Jędruchniewicz ◽

...

Keyword(s):

Heavy Metals ◽

Fly Ash ◽

Active Sites ◽

Nitrogen Adsorption ◽

Carbon Composite ◽

Hard Coal ◽

Adsorbent Surface ◽

Developed Surface ◽

X Zeolite ◽

Adsorption Desorption

Pure zeolite (Na-X) and a zeolite–carbon composite (Na-X(C)) were investigated as adsorbents of heavy metals—Pb2+ and Zn2+ from an aqueous solution. These materials were synthesized from fly ash—a waste from conventional hard coal combustion. Both solids were characterized using XRD, SEM-EDS, nitrogen adsorption/desorption, particle size and elemental composition analyses. The adsorption study was performed at pH 5 in the systems containing one or two adsorbates simultaneously. The obtained results showed that the pure zeolite was characterized by a more developed surface area (728 m2/g) than its carbon composite (272 m2/g), and the mean pore diameters were equal to 1.73 and 2.56 nm, respectively. The pure Na-X zeolite showed better adsorption properties towards heavy metals than its Na-X(C) composite, and Zn2+ adsorbed amounts were significantly higher than the Pb2+ ones (the highest experimental adsorption levels were: for Zn2+—656 and 600 mg/g, and for Pb2+—575 and 314 mg/g, on the Na-X and Na-X(C) surfaces, respectively). The zinc ions are exchanged with the cations inside the zeolite materials structure more effectively than lead ions with a considerably larger size. In the mixed systems, the competition between both heavy metals for access to the active sites on the adsorbent surface leads to the noticeable reduction in their adsorbed amounts. Moreover, the hydrochloric acid was a better desorbing agent for both heavy metals, especially Pb2+ one (desorption reached 78%), than sodium base (maximal desorption 25%).

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Preparation and characterization of Chicory leaf powder and its application as a nano-native plant sorbent for removal of Acid Blue 25 from aqueous media: isotherm, kinetic and thermodynamic study of the adsorption phenomenon

Journal of Nanostructure in Chemistry ◽

10.1007/s40097-019-00330-z ◽

2020 ◽

Vol 10 (1) ◽

pp. 75-86 ◽

Cited By ~ 1

Author(s):

Maryam Haghighizadeh ◽

Karim Zare ◽

Hossein Aghaie ◽

Majid Monajjemi

Keyword(s):

Aqueous Media ◽

Thermodynamic Study ◽

Native Plant ◽

Adsorption Phenomenon ◽

Leaf Powder ◽

Acid Blue 25 ◽

Kinetic And Thermodynamic Study ◽

Acid Blue

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Synthesis of Valeric Acid by Selective Electrocatalytic Hydrogenation of Biomass-Derived Levulinic Acid

Catalysts ◽

10.3390/catal10060692 ◽

2020 ◽

Vol 10 (6) ◽

pp. 692

Author(s):

Yan Du ◽

Xiao Chen ◽

Ji Qi ◽

Pan Wang ◽

Changhai Liang

Keyword(s):

Levulinic Acid ◽

Active Sites ◽

Valeric Acid ◽

Future Research ◽

Adsorbed Hydrogen ◽

Electrocatalytic Hydrogenation ◽

Ambient Conditions ◽

Metallic Lead ◽

Faradaic Efficiency ◽

Lead Electrode

The electrocatalytic hydrogenation (ECH) of biomass-derived levulinic acid (LA) is a promising strategy to synthetize fine chemicals under ambient conditions by replacing the thermocatalytic hydrogenation at high temperature and high pressure. Herein, various metallic electrodes were investigated in the ECH of LA in a H-type divided cell. The effects of potential, electrolyte concentration, reactant concentration, and temperature on catalytic performance and Faradaic efficiency were systematically explored. The high conversion of LA (93%) and excellent “apparent” selectivity to valeric acid (VA) (94%) with a Faradaic efficiency of 46% can be achieved over a metallic lead electrode in 0.5 M H2SO4 electrolyte containing 0.2 M LA at an applied voltage of −1.8 V (vs. Ag/AgCl) for 4 h. The combination of adsorbed LA and adsorbed hydrogen (Hads) on the surface of the metallic lead electrode is key to the formation of VA. Interestingly, the reaction performance did not change significantly after eight cycles, while the surface of the metallic lead cathode became rough, which may expose more active sites for the ECH of LA to VA. However, there was some degree of corrosion for the metallic lead cathode in this strong acid environment. Therefore, it is necessary to improve the leaching-resistance of the cathode for the ECH of LA in future research.

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