scholarly journals Phosphate has a differential influence on arsenate adsorption by soils with different properties

2012 ◽  
Vol 58 (No. 9) ◽  
pp. 405-411 ◽  
Author(s):  
X. Zeng ◽  
P. Wu ◽  
S. Su ◽  
L. Bai ◽  
Q. Feng
Keyword(s):  
Adsorption Capacity ◽  
Agricultural Soils ◽  
Molar Ratio ◽  
Adsorption Sites ◽  
Adsorption Capacities ◽  
Minimum Capacity ◽  
P Application ◽  
As Adsorption ◽  
Langmuir And Freundlich Equations ◽  
Different Soils

The adverse effect of the application of phosphorus (P) on arsenic (As) adsorption by soils can result in increasing mobility and availability of As. However, in different soils, P might influence As adsorption differently. In this study, the arsenate [As<sup>(V)</sup>] adsorption capacities of six soils with different properties and the effects of P application were studied. The results indicated that the adsorbed As<sup>(V)</sup> contents all increased as a function of the As<sup>(V)</sup> content in equilibrium. When analysed using the Langmuir and Freundlich equations, the maximum As<sup>(V)</sup> adsorption capacity of 0.72 mg/g was found for an Alumi-Plinthic Acrisol, while the minimum capacity of 0.09 mg/g was observed for an Epigleyic Cambisol. The adverse effects of P application on As<sup>(V)</sup> adsorption by the six soils were observed to be variable. When the P/As molar ratio in a culture experiment was increased from 0 to 10, the maximal and minimal decreases in the As<sup>(V)</sup> adsorption capacity of 0.086 and 0.014 mg/g were found in the Alumi-Plinthic Acrisol and Epigleyic Cambisol, respectively. P was relatively more effective in competing for adsorption sites with As<sup>(V)</sup> in the Alumi-Plinthic Acrisol and Luvi-Endogleyic Phaeozem due to their higher A/P values (decrease in adsorbed<br />As/added P) of 1.143 and 1.135, respectively. These results will help decrease the environmental risk of some As-contaminated agricultural soils through the controlled application of P.

scholarly journals Effects of Calcination Temperature and Chemical Modification on the Adsorption of Cd and As(V) by Biochar Derived from Pteris Vittata

2021 ◽  
Author(s):  
Kazuki Sugawara ◽  
Kouhei Ichio ◽  
Yumiko Ichikawa ◽  
Hitoshi Ogawa ◽  
Seiichi Suzuki
Keyword(s):  
Chemical Modification ◽  
Adsorption Capacity ◽  
Toxic Elements ◽  
Plant Biomass ◽  
Pteris Vittata ◽  
Adsorption Capacities ◽  
Biomass Resources ◽  
As Adsorption ◽  
Effective Use ◽  
Very High

Abstract Phytoremediation can be applied successfully to solve the serious worldwide issue of arsenic (As) and cadmium (Cd) pollution. However, the treatment of biomass containing toxic elements after remediation is a challenge. In this study, we investigated the effective use of biomass resources by converting the As hyperaccumulator P. vittata into biochar to adsorb toxic elements. Plant biomass containing As was calcined at 600 °C, 800 °C, and 1200 °C and its surface structure and adsorption performances for As and Cd were evaluated. Calcination at 1200 °C increased the specific surface area of the biochar, but it did not significantly affect its adsorption capacity for toxic elements. The calcined biochar had very high adsorption capacities of 90% and 95% for As and Cd, respectively, adsorbing 450 mg/g-biochar of both elements. The As adsorption rate was improved by FeCl3 treatment. However, the adsorption capacity for Cd was not significantly affected by the NaOH treatment. In conclusion, it was found that after phytoremediation using P. vittata biomass, it can be effectively used as an environmental purification material by conversion to biochar. Furthermore, chemical modification with FeCl3 improves the biochar’s adsorption performance.

scholarly journals Comparative Study on the Adsorption Capacities of the Three Black Phosphorus-Based Materials for Methylene Blue in Water

2020 ◽  
Vol 12 (20) ◽  
pp. 8335
Author(s):  
Juanhong Wang ◽  
Zhaocheng Zhang ◽  
Dongyang He ◽  
Hao Yang ◽  
Dexin Jin ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Black Phosphorus ◽  
Adsorption Effect ◽  
Adsorption Sites ◽  
Surface Areas ◽  
Adsorption Behaviors ◽  
Adsorption Capacities ◽  
Reduced Graphene ◽  
Black Phosphorene

Dye effluent has attracted considerable attention from worldwide researchers due to its harm and toxicity in recent years; as a result, the treatment for dye has become one of the focuses in the environmental field. Adsorption has been widely applied in water treatment owing to its various advantages. However, the adsorption behaviors of the new materials, such as the 2D black phosphorus (BP), for pollution were urgently revealed and improved. In this work, BP, black phosphorene (BPR), and sulfonated BPR (BPRS) were prepared by the vapor phase deposition method, liquid-phase exfoliating method, and modification with sulfonation, respectively. The three BP-based materials were characterized and used as adsorbents for the removal of methylene blue (MB) in water. The results showed that the specific surface areas (SSAs) of BP, BPR, and BPRS were only 6.78, 6.92, and 7.72 m2·g−1, respectively. However, the maximum adsorption capacities of BP, BPR, and BPRS for MB could reach up to 84.03, 91.74, and 140.85 mg·g−1, which were higher than other reported materials with large SSAs such as graphene (GP), nanosheet/magnetite, and reduced graphene oxide (rGO). In the process of BP adsorbing MB, wrinkles were generated, and the wrinkles would further induce adsorption. BPR had fewer layers (3–5), more wrinkles, and stronger adsorption capacity (91.74 mg·g−1). The interactions between the BP-based materials and MB might cause the BP-based materials to deform, i.e., to form wrinkles, thereby creating new adsorption sites between layers, and then further inducing adsorption. Although the wrinkles had a certain promotion effect, the adsorption capacity was limited, so the sulfonic acid functional group was introduced to modify BPR to increase its adsorption sites and promote the adsorption effect. These findings could provide a new viewpoint and insight on the adsorption behavior and potential application of the BP-based materials.

scholarly journals Adsorption of Reactive Brilliant Blue XBR onto Polymeric Adsorbents from Single- and Binary-Solute Solutions

2005 ◽  
Vol 23 (3) ◽  
pp. 235-244 ◽  
Author(s):  
Lu Zhaoyang ◽  
Long Chao ◽  
Li Aimin ◽  
Jiang Zhenmao ◽  
Liu Wei ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Competitive Adsorption ◽  
Brilliant Blue ◽  
Adsorption Selectivity ◽  
Polymeric Adsorbent ◽  
Ionic Polymer ◽  
Adsorption Sites ◽  
Adsorption Capacities ◽  
Direct Competition ◽  
Polymer Adsorbent

A non-ionic polymer adsorbent (NPA) and its aminated polymeric adsorbent (APA) were prepared and characterized towards adsorption from aqueous solution. Two adsorbates, Reactive Brilliant Blue XBR and 2,4-diaminobenzene sulphonic acid (ABSA), were chosen as adsorbates for competitive adsorption from single-solute solution and binary-solute systems onto the two adsorbents prepared. The results showed that APA, the polymer obtained after amination, exhibited a higher adsorption capacity than NPA towards XBR from the single-solute solution. However, in binary-solute solution adsorption, the presence of ABSA reduced the adsorption capacity towards XBR due to direct competition between XBR and ABSA for the same adsorption sites. This resulted in similar adsorption capacities towards XBR for NPA and APA. Moreover, the adsorption selectivity coefficients obtained for XBR onto ABSA in simultaneous adsorption tests suggested that NPA exhibited more favourable adsorption properties towards the adsorption of XBR from binary-solute systems than APA.

scholarly journals Molecular simulation of gases competitive adsorption in lignite and analysis of original CO desorption

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jing Zhang ◽  
Jiren Wang ◽  
Chunhua Zhang ◽  
Zongxiang Li ◽  
Jinchao Zhu ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Molecular Simulation ◽  
Competitive Adsorption ◽  
Air Leakage ◽  
Adsorption Characteristics ◽  
Adsorption Sites ◽  
Simulation Based ◽  
Lignite Coal ◽  
Model C ◽  
Grand Canonical

AbstractTo study the adsorption characteristics of CO, CO2, N2, O2, and their binary-components in lignite coal, reveal the influence of CO2 or N2 injection and air leakage on the desorption of CO in goafs, a lignite model (C206H206N2O44) was established, and the supercell structure was optimized under temperatures of 288.15–318.15 K for molecular simulation. Based on molecular dynamics, the Grand Canonical Monte Carlo method was used to simulate the adsorption characteristics and the Langmuir equation was used to fit the adsorption isotherms of gases. The results show that for single-components, the order of adsorption capacity is CO2 > CO > O2 > N2. For binary-components, the competitive adsorption capacities of CO2 and CO are approximate. In the low-pressure zone, the competitive adsorption capacity of CO2 is stronger than that of CO, and the CO is stronger than N2 or O2. From the simulation, it can be seen that CO2, N2 or O2 will occupy adsorption sites, causing CO desorption. Therefore, to prevent the desorption of the original CO in the goaf, it is not suitable to use CO2 or N2 injection for fire prevention, and the air leakage at the working faces need to be controlled.

scholarly journals One-step synthesis of nitrogen-grafted copper-gallic acid for enhanced methylene blue removal

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shella Permatasari Santoso ◽  
Vania Bundjaja ◽  
Artik Elisa Angkawijaya ◽  
Chintya Gunarto ◽  
Alchris Woo Go ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Gallic Acid ◽  
Synthesis Method ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
One Step ◽  
Detailed Assessment ◽  
Higher Temperature

AbstractNitrogen-grafting through the addition of glycine (Gly) was performed on a metal- phenolic network (MPN) of copper (Cu2+) and gallic acid (GA) to increase its adsorption capacity. Herein, we reported a one-step synthesis method of MPN, which was developed according to the metal–ligand complexation principle. The nitrogen grafted CuGA (Ng-CuGA) MPN was obtained by reacting Cu2+, GA, and Gly in an aqueous solution at a molar ratio of 1:1:1 and a pH of 8. Several physicochemical measurements, such as Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), N2 sorption, X-ray diffraction (XRD), and thermal gravimetry analysis (TGA), were done on Ng-CuGA to elucidate its characteristics. The analysis revealed that the Ng-CuGA has non-uniform spherical shaped morphology with a pore volume of 0.56 cc/g, a pore size of 23.25 nm, and thermal stability up to 205 °C. The applicational potential of the Ng-CuGA was determined based on its adsorption capacity against methylene blue (MB). The Ng-CuGA was able to adsorb 190.81 mg MB per g adsorbent at a pH of 6 and temperature of 30 °C, which is 1.53 times higher than the non-grafted CuGA. Detailed assessment of Ng-CuGA adsorption properties revealed their pH- and temperature-dependent nature. The adsorption capacity and affinity were found to decrease at a higher temperature, demonstrating the exothermic adsorption behavior.

scholarly journals The Adsorption of Chloromethanes on KCl. The Role of the Surface Ions as Adsorption Sites

1983 ◽  
Vol 56 (7) ◽  
pp. 2086-2089 ◽  
Author(s):  
Masatoshi Chikazawa ◽  
Masatoshi Amada ◽  
Takafumi Kanazawa
Keyword(s):  
Adsorption Sites ◽  
As Adsorption

scholarly journals Enhancement of the Congo Red Adsorption Capacity of Biochars by Surface Modification with MgCl2 Pretreatment

2020 ◽  
Vol 42 (10) ◽  
pp. 472-481
Author(s):  
Hee So Oh ◽  
Jae-Soo Chang
Keyword(s):  
Surface Modification ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Congo Red ◽  
Raw Materials ◽  
Physicochemical Characteristics ◽  
Pine Sawdust ◽  
Adsorption Capacities ◽  
Initial Ph ◽  
Surface Modified

Objectives : The physicochemical characteristics of Mg-biochar composites derived from kelp and pine after pretreatment with MgCl2 were analyzed, and their adsorption capacities for an anionic dye, Congo red (CR), were evaluated.Methods : After pretreating 60 g of kelp and pine sawdust in 1 L of 0.1 M MgCl2･6H2O, the raw materials were pyrolyzed at 500℃ to produce Mg-biochar composites (kelp based KB-Mg and pine based PB-Mg). The fundamental physicochemical characteristics of the Mg-biochar composites were examined, and their adsorption capacities for CR were investigated using different initial pH values, adsorption kinetic models, and adsorption isotherm models.Results and discussion : The Mg-biochar composites showed the development of uniform deposits of Mg minerals primarily as MgO crystal on the surface by the surface modification with MgCl2. When the pristine biochars were surface-modified with MgCl2, their adsorption capacities for CR were significantly increased over the entire pH range tested. The CR adsorption process by all biochars was best described with the pseudo-first order kinetics model, and the adsorption isotherm characteristics were better described with the Langmuir isotherm model for all biochars. The Langmuir maximum adsorption capacities for KB-Mg and PB-Mg were 423.0 mg/g and 394.7 mg/g, respectively. It is suggested that the main mechanism for CR adsorption on the Mg-biochars is electrostatic attraction between CR and the biochars.Conclusions : The results showed that surface modification with MgCl2 could greatly enhance the CR adsorption capacity of biochars, and the results demonstrated the great potential of KB-Mg and PB-Mg for CR removal.

Experimental Study of Adsorption of Ammonia Nitrogen from Wastewater onto the Bagasse Adsorbent

2014 ◽  
Vol 529 ◽  
pp. 22-25 ◽  
Author(s):  
Li Wei Xie ◽  
Ze Long Xu ◽  
Yan Hua Huang ◽  
Shuang Cao ◽  
Zong Qiang Zhu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Experimental Study ◽  
Adsorption Capacity ◽  
Ammonia Nitrogen ◽  
Alkaline Condition ◽  
Maximum Adsorption Capacity ◽  
Initial Concentration ◽  
Adsorption Capacities ◽  
Neutrality Condition ◽  
Adsorbent Dose

Adsorption of ammonia nitrogen from aqueous solution onto the bagasse adsorbent has been investigated to evaluate the effects of Adsorbent dose, initial NH4+-N concentration, and pH on the removal systematically. With increasing initial concentration, the amount of ammonia nitrogen sorbed onto the adsorbent increased until it gradually decreased due to the initial concentration exceed 50 mg·L-1, and the maximum adsorption capacity was observed for the sample to be 1.31 mg·g-1 at the initial concentration of 30 mg·L-1, and the corresponding removal rates decreased from 94.01 to 3.89%, with increase in initial concentration from 5 to 100 mg·L-1. Adsorption capacities decreased from 6.04 to 0.49 mg·g-1 with increasing adsorbent dose from 0.1 to 1.5g. What’s more, under alkaline condition, the removal efficiency of ammonia nitrogen from aqueous solution onto the samples were superior to that under acidity and neutrality condition.

Scalable Sulfonate-Coated Cotton Fibers as Facile Recyclable and Biodegradable Adsorbents for Highly Efficient Removal of Cationic Dyes

2021 ◽  
Author(s):  
Linhua Li ◽  
Baojie Dou ◽  
Jianwu Lan ◽  
Jiaojiao Shang ◽  
Yafang Wang ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Large Scale ◽  
Ph Value ◽  
Cationic Dyes ◽  
Cotton Fibers ◽  
Wastewater Remediation ◽  
Efficient Removal ◽  
Adsorption Sites ◽  
Highly Efficient ◽  
Coated Cotton

Abstract Adsorbents with superior adsorption capacity and facile recyclability are viewed as promising materials for dye wastewater treatment. In this work, a novel sulfonate decorated cotton fiber as a biodegradable and recyclable adsorbent was fabricated for highly efficient removal of cationic dyes. Herein, the poly(sodium p-styrenesulfonate-co-N-methylol acrylamide) (P(SSNa-co-NMAM)) with SSNa units as adsorption sites and NMAM units as thermal-crosslinking points was synthesized for modification of cotton fibers in a large scale at high temperature (160 oC). The various characterization investigations confirmed the successful construction of the P(SSNa-co-NMAM) coated cotton fibers (PCF). As expected, the as-obtained adsorbent presented outstanding adsorption performance toward cationic dyes in the both static and dynamic states, even in the synthetic effluent. The adsorption processes of cationic dyes onto the PCF were well fitted by the Langmuir isotherm model and Pseudo-second-order kinetics, respectively. The thermodynamics study showed that the adsorption reaction of the cationic dyes onto PCF was a spontaneous and endothermic process. The maximum adsorption capacities of PCF toward MEB, RhB and MG were 3976.10, 2879.80 and 3071.55 mg/g, respectively. The responsible adsorption of dyes ontothe PCF was electrostatic interaction. Moreover, the adsorption capacity of PCF toward cationic dyes was slight influenced by pH value of solution, because of the stable feature of sulfonate moiety in acid and alkali. In addition, the as-prepared PCF exhibited satisfactory recyclability and reusability. Given the aforementioned results, the as-obtained PCF is a promising adsorbent with great potential for practical application in the dye-contaminated wastewater remediation.

scholarly journals Supercritical CO2 Exposure-Induced Surface Property, Pore Structure, and Adsorption Capacity Alterations in Various Rank Coals

Energies ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 3294 ◽  
Author(s):  
Zhenjian Liu ◽  
Zhenyu Zhang ◽  
Xiaoqian Liu ◽  
Tengfei Wu ◽  
Xidong Du
Keyword(s):  
Coal Seam ◽  
Pore Structure ◽  
Adsorption Capacity ◽  
Surface Property ◽  
Supercritical Co2 ◽  
Co2 Adsorption ◽  
Low Pressure ◽  
Coal Seam Gas ◽  
Adsorption Sites ◽  
Co2 Adsorption Capacity

Carbon dioxide (CO2) has been used to replace coal seam gas for recovery enhancement and carbon sequestration. To better understand the alternations of coal seam in response to CO2 sequestration, the properties of four different coals before and after supercritical CO2 (ScCO2) exposure at 40 °C and 16 MPa were analyzed with Fourier Transform infrared spectroscopy (FTIR), low-pressure nitrogen, and CO2 adsorption methods. Further, high-pressure CO2 adsorption isotherms were performed at 40 °C using a gravimetric method. The results indicate that the density of functional groups and mineral matters on coal surface decreased after ScCO2 exposure, especially for low-rank coal. With ScCO2 exposure, only minimal changes in pore shape were observed for various rank coals. However, the micropore specific surface area (SSA) and pore volume increased while the values for mesopore decreased as determined by low-pressure N2 and CO2 adsorption. The combined effects of surface property and pore structure alterations lead to a higher CO2 adsorption capacity at lower pressures but lower CO2 adsorption capacity at higher pressures. Langmuir model fitting shows a decreasing trend in monolayer capacity after ScCO2 exposure, indicating an elimination of the adsorption sites. The results provide new insights for the long-term safety for the evaluation of CO2-enhanced coal seam gas recovery.

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