Adsorption of cadmium by biochar produced from pyrolysis of corn stalk in aqueous solution

2016 ◽  
Vol 74 (6) ◽  
pp. 1335-1345 ◽  
Author(s):  
Fengfeng Ma ◽  
Baowei Zhao ◽  
Jingru Diao
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Ionic Strength ◽  
Ph Value ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Corn Stalk ◽  
Adsorbent Dosage ◽  
Initial Ph ◽  
Adsorbent Particle

The purpose of this work is to investigate adsorption characteristic of corn stalk (CS) biochar for removal of cadmium ions (Cd2+) from aqueous solution. Batch adsorption experiments were carried out to evaluate the effects of pH value of solution, adsorbent particle size, adsorbent dosage, and ionic strength of solution on the adsorption of Cd2+ onto biochar that was pyrolytically produced from CS at 300 °C. The results showed that the initial pH value of solution played an important role in adsorption. The adsorptive amount of Cd2+ onto the biochar decreased with increasing the adsorbent dosage, adsorbent particle size, and ionic strength, while it increased with increasing the initial pH value of solution and temperature. Cd2+ was removed efficiently and quickly from aqueous solutions by the biochar with a maximum capacity of 33.94 mg/g. The adsorption process was well described by the pseudo-second-order kinetic model with the correlation coefficients greater than 0.986. The adsorption isotherm could be well fitted by the Langmuir model. The thermodynamic studies showed that the adsorption of Cd2+ onto the biochar was a spontaneous and exothermic process. The results indicate that CS biochar can be considered as an efficient adsorbent.

Adsorption Characteristics of Phenol in Aqueous Solution by Pinus massoniana Biochar

2013 ◽  
Vol 295-298 ◽  
pp. 1154-1160 ◽  
Author(s):  
Guo Zhi Deng ◽  
Xue Yuan Wang ◽  
Xian Yang Shi ◽  
Qian Qian Hong
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Pinus Massoniana ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Salt Ions ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.

Biosorption of hexavalent chromium from aqueous solution by polyethyleneimine-modified ultrasonic-assisted acid hydrochar from Sargassum horneri

2020 ◽  
Vol 81 (6) ◽  
pp. 1114-1129 ◽  
Author(s):  
Jun Wang ◽  
Qinglong Xie ◽  
Ao Li ◽  
Xuejun Liu ◽  
Fengwen Yu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Batch Adsorption ◽  
Crosslinking Reaction ◽  
Order Kinetic ◽  
Adsorption Capacities ◽  
Initial Ph ◽  
Ultrasonic Assisted ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Abstract In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.

scholarly journals Adsorption of methylene blue from aqueous solutions by pyrolusite ore

2018 ◽  
Vol 18 (44) ◽  
pp. 5-11 ◽  
Author(s):  
Nizamettin Demirkıran ◽  
G D Turhan Özdemir ◽  
M Saraç ◽  
M Dardağan
Keyword(s):  
Methylene Blue ◽  
Particle Size ◽  
Contact Time ◽  
Average Particle Size ◽  
Dye Adsorption ◽  
Blue Dye ◽  
Average Particle ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Initial Ph

In this study, the adsorption of methylene blue dye was examined by using pyrolusite ore as a low-cost alternative adsorbent source. Pyrolusite, which contains mainly MnO2, is a manganese ore. The effects of the initial concentration of dye, contact time, initial pH of solution, adsorbent dosage, stirring speed of solution, and average particle size of adsorbent on the adsorption of methylene blue were studied. It was found that the percentage of the adsorbed dye increased with increasing the amount of pyrolusite. While the initial dye concentration, initial pH, contact time, stirring speed, particle size, and adsorbent dosage were 25 ppm, 6, 90 min, 250 rpm, 63 µm, and 12 g/l, respectively, the efficiency of dye adsorption on pyrolusite ore was 99%. The isotherm and kinetic studies relating to this adsorption process were also made. It was found that the equilibrium data followed the Langmuir isotherm model while the kinetic of process could be described by the pseudo-second order kinetic model.

scholarly journals The efficiency of nano-TiO2 and γ-Al2O3 in copper removal from aqueous solution by characterization and adsorption study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fatemeh Ezati ◽  
Ebrahim Sepehr ◽  
Fatemeh Ahmadi
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Ph Value ◽  
Physical Adsorption ◽  
Geochemical Modeling ◽  
Low Cost ◽  
Background Electrolyte ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Equilibrium Data

AbstractWater pollution is a major global challenge given the increasing growth in the industry and the human population. The present study aims to investigate the efficiency of TiO2 and γ-Al2O3 nanoadsorbents for removal of copper (Cu(II)) from aqueous solution as influenced by different chemical factors including pH, initial concentration, background electrolyte and, ionic strength. The batch adsorption experiment was performed according to standard experimental methods. Various isotherm models (Freundlich, Langmuir, Temkin, and Dubinin–Radushkevich) were fitted to the equilibrium data. According to geochemical modeling data, adsorption was a predominant mechanism for Cu(II) removal from aqueous solution. Calculated isotherm equations parameters were evidence of the physical adsorption mechanism of Cu(II) onto the surface of the nanoparticles. The Freundlich adsorption isotherm model could well fit the experimental equilibrium data at different pH values. The maximum monolayer adsorption capacity of TiO2 and γ-Al2O3 nanosorbents were found to 9288 and 3607 mg kg−1 at the highest pH value (pH 8) and the highest initial Cu(II) concentration (80 mg L−1) respectively. Copper )Cu(II) (removal efficiency with TiO2 and γ-Al2O3 nanoparticles increased by increasing pH. Copper )Cu(II) (adsorption deceased by increasing ionic strength. The maximum Cu(II) adsorption (4510 mg kg−1) with TiO2 nanoparticles was found at 0.01 M ionic strength in the presence of NaCl. Thermodynamic calculations show the adsorption of Cu(II) ions onto the nanoparticles was spontaneous in nature. Titanium oxide (TiO2) nanosorbents could, therefore, serve as an efficient and low-cost nanomaterial for the remediation of Cu(II) ions polluted aqueous solutions.

scholarly journals Adsorption and desorption studies of <i>Delonix regia</i> pods and leaves: removal and recovery of Ni(II) and Cu(II) ions from aqueous solution

2020 ◽  
Vol 13 (2) ◽  
pp. 15-27 ◽  
Author(s):  
Bolanle M. Babalola ◽  
Adegoke O. Babalola ◽  
Cecilia O. Akintayo ◽  
Olayide S. Lawal ◽  
Sunday F. Abimbade ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Metal Ions ◽  
Metal Ion ◽  
Agricultural Waste ◽  
Waste Product ◽  
Operating Conditions ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Delonix Regia

Abstract. In this study, the adsorption of Ni(II) and Cu(II) ions from aqueous solutions by powdered Delonix regia pods and leaves was investigated using batch adsorption techniques. The effects of operating conditions such as pH, contact time, adsorbent dosage, metal ion concentration and the presence of sodium ions interfering with the sorption process were investigated. The results obtained showed that equilibrium sorption was attained within 30 min of interaction, and an increase in the initial concentration of the adsorbate, pH and adsorbent dosage led to an increase in the amount of Ni(II) and Cu(II) ions adsorbed. The adsorption process followed the pseudo-second-order kinetic model for all metal ions' sorption. The equilibrium data fitted well with both the Langmuir and Freundlich isotherms; the monolayer adsorption capacity (Q0 mg g−1) of the Delonix regia pods and leaves was 5.88 and 5.77 mg g−1 for Ni(II) ions respectively and 9.12 and 9.01 mg g−1 for Cu(II) ions respectively. The efficiency of the powdered pods and leaves of Delonix regia with respect to the removal of Ni(II) and Cu(II) ions was greater than 80 %, except for the sorption of Ni(II) ions onto the leaves. The desorption study revealed that the percentage of metal ions recovered from the pods was higher than that recovered from the leaves at various nitric acid concentrations. This study proves that Delonix regia biomass, an agricultural waste product (“agro-waste”), could be used to remove Ni(II) and Cu(II) ions from aqueous solution.

Kinetic Studies of Adsorption of Disperse Blue 2BLN from Aqueous Solution by Expanded Graphite

2011 ◽  
Vol 148-149 ◽  
pp. 357-360
Author(s):  
Jin Bo Huang ◽  
Min Cong Zhu ◽  
Zhi Fang Zhou ◽  
Hong Xia Zhang
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Ph Value ◽  
Expanded Graphite ◽  
Kinetic Studies ◽  
Second Order ◽  
Batch Adsorption ◽  
Initial Ph ◽  
Intra Particle Diffusion ◽  
Pseudo Second Order

Expanded graphite (EG) was prepared by microwave irradiation and evaluated as adsorbent for the removal of disperse blue 2BLN (DB) from aqueous solution by the batch adsorption technique under different conditions of initial pH value, adsorbent dosage, initial dye concentration and contact time. The experimental data were analyzed considering pseudo-first-order, pseudo-second-order and intra-particle diffusion approaches. The adsorption kinetics at room temperature could be expressed by the pseudo second order model very well. The results indicate that the adsorption rate is fast enough and more than eighty percent of the adsorbed DB can be removed in the first 15 min at room temperature, which makes the process practical for industrial application.

scholarly journals Potential Biosorbent Derived fromCalligonum polygonoidesfor Removal of Methylene Blue Dye from Aqueous Solution

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Asma Nasrullah ◽  
Hizbullah Khan ◽  
Amir Sada Khan ◽  
Zakaria Man ◽  
Nawshad Muhammad ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Particle Size ◽  
Second Order ◽  
Blue Dye ◽  
Order Kinetic ◽  
Particle Size Analyzer ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Kinetics Of

The ash ofC. polygonoides(locally called balanza) was collected from Lakki Marwat, Khyber Pakhtunkhwa, Pakistan, and was utilized as biosorbent for methylene blue (MB) removal from aqueous solution. The ash was used as biosorbent without any physical or chemical treatment. The biosorbent was characterized by using various techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The particle size and surface area were measured using particle size analyzer and Brunauer-Emmett-Teller equation (BET), respectively. The SEM and BET results expressed that the adsorbent has porous nature. Effects of various conditions such as initial concentration of methylene blue (MB), initial pH, contact time, dosage of biosorbent, and stirring rate were also investigated for the adsorption process. The rate of the adsorption of MB on biomass sample was fast, and equilibrium has been achieved within 1 hour. The kinetics of MB adsorption on biosorbent was studied by pseudo-first- and pseudo-second-order kinetic models and the pseudo-second-order has better mathematical fit with correlation coefficient value (R2) of 0.999. The study revealed thatC. polygonoidesash proved to be an effective, alternative, inexpensive, and environmentally benign biosorbent for MB removal from aqueous solution.

scholarly journals Investigation of effectiveness of pyrolysis products on removal of alizarin yellow GG from aqueous solution: a comparative study with commercial activated carbon

2020 ◽  
Vol 81 (6) ◽  
pp. 1191-1208 ◽  
Author(s):  
Nihan Kaya ◽  
Zeynep Yildiz Uzun
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Surface Area ◽  
Bet Surface Area ◽  
Walnut Shell ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Pine Cone ◽  
Alizarin Yellow

Abstract The increasing use of dyestuff in industrial applications brings with it environmental problems. These dyes, which are an eco-toxic hazard, are common water pollutants, even at very low concentrations in water resources. Therefore, they must be removed in an economical way. In this study, low-cost biosorbents such as pine cone char, walnut shell char, and hazelnut shell char were prepared by pyrolysis process at different carbonization temperatures in the range of 400–700 °C. Biochars with the highest surface area were used to remove alizarin yellow GG from aqueous solution and the adsorption capacities of these materials were compared to commercially available activated carbon. Biomasses and prepared biochars were characterized using Fourier transform infrared spectroscopy, thermogravimetric/differential thermogravimetry analysis, Brunauer–Emmett–Teller (BET), scanning electron microscopy/energy dispersive X-ray spectroscopy, partial and elemental analysis techniques. Operational parameters such as contact time, temperature, pH, adsorbent dosage, and initial dye concentration were considered as variables for the batch adsorption experiments. Among the biochars used, the highest adsorption efficiency (82%) was obtained in pine cone char (BET surface area 259.74 m2/g) at pH = 3, T = 45 °C, adsorbent dosage of 8 g/L, and initial dye concentration of 20 ppm. The adsorption mechanism has been investigated by applying different kinetic and isotherm models with the aid of time-dependent adsorption data. The adsorption process was best described by Langmuir isotherm and pseudo-second order kinetic model.

Adsorption of Cu2+ from Aqueous Solution by Walnut Shell

2013 ◽  
Vol 864-867 ◽  
pp. 1327-1332 ◽  
Author(s):  
Xiu Guo Lu ◽  
Pei Pei Yan ◽  
Xiao Fang Dang
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Metal Ions ◽  
Adsorption Capacity ◽  
Removal Rate ◽  
Equilibrium Concentration ◽  
Walnut Shell ◽  
Adsorption Time ◽  
Adsorbent Dosage ◽  
Initial Ph

Walnut shell was used as adsorbent to remove Cu2+ metal ions from the simulated aqueous solution. The influence of factors, namely: particle size, initial pH, oscillation intensity, adsorbent dosage and adsorption time were investigated through single factor experiments.The results show that, the adsorption capacity reached the peak for Cu2+ in 25°C when the initial pH was 5, particle size was 1.25~1.6mm, adsorbent dosage was2.5g, oscillation speed reached 200r/min, and the adsorption time was 360min, all above leads the removal rate of Cu2+reached 75.7%, and the adsorption capacity of Cu2+ 0.702 mg/g. The pseudo-second-order model was fitted to describe the adsorption of Cu2+ , it was shown that adsorption rate for the metal ions in proportion to the square of the concentration.The equilibrium concentration of adsorption fitted well with Langmuir isotherm equation, the process of adsorption was single molecular layer adsorption.

Immobilization of Persimmon Tannin on Cellulose Viscopearls and Removal of Caffeine from Aqueous Solution

2015 ◽  
Vol 1767 ◽  
pp. 93-105
Author(s):  
Dennise Alejandra Murguía Flores ◽  
Ahmad La Ode ◽  
Ko-Ki Kunimoto ◽  
Jaime Bonilla Ríos
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Adsorption Capacity ◽  
Batch Adsorption ◽  
Caffeine Concentration ◽  
Sem Images ◽  
Adsorbent Dosage ◽  
Equilibrium Data ◽  
Particle Size And Shape ◽  
Water Contents

ABSTRACTAn eco-friendly adsorbent was prepared by immobilization of Persimmon Tannin (PT) in cellulose viscopearls to remove caffeine. The immobilization time within a range of 1-42days was performed. Batch adsorption experiments were studied for different Persimmon Tannin on Cellulose Viscopearls (PTIC) gel samples, adsorbent dosage, and initial caffeine concentration. FTIR indicated that PT was successfully immobilized onto viscopearls. SEM images showed differences especially on particle size and shape, between control, day7, and day28 of PTIC gel samples. The adsorption capacity results showed that removal of caffeine as the amount of adsorbed increased, the percentage of caffeine adsorption increased accordingly, but it decreased with the increased in initial caffeine concentration. Results for different PTIC gel samples showed that day 42 PTIC sample exhibits the highest adsorption capacity of caffeine solution of 43.3mg/g. The samples showed water contents in the range of 343-324%.The equilibrium data were analyzed using Freundlich and Langmuir equations. It suggested that viscopearls acted to be a suitable insoluble matrix to immobilized PT, instead of using crosslinkers.

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