scholarly journals Adsorption of sulfamethoxazole by wheat straw-derived biochars in seawater

2021 ◽  
Vol 251 ◽  
pp. 02036
Author(s):  
Man Zhao ◽  
Mengying Shao ◽  
Xiaohan Ma
Keyword(s):  
Wheat Straw ◽  
Marine Environment ◽  
Removal Rate ◽  
Low Cost ◽  
Organic Pollutant ◽  
Maximum Adsorption Capacity ◽  
Adsorption Characteristic ◽  
Initial Concentration ◽  
High Pollution ◽  
Maximum Removal

The excessive use of antibiotics in mariculture have resulted in high pollution burdens of antibiotics in marine environment. Biochars, as promising adsorbents, have been widely used in organic pollutant adsorption because of their good adsorption performance and stability. However, adsorption characteristic of antibiotics in seawater by biochar is not well known. Thus, the batch experiment for the adsorption of sulfamethoxazole (SMX) was conducted using wheat straw-derived biochars and graphite (GR) under different initial concentration of SMX and different addition of adsorbent in seawater. The results showed that the wheat straw-derived biochars produced at 700 °C was the optimal adsorbent with the maximum removal rate (R) of 70.3%, the maximum adsorption capacity (Qe) of 1.03 mg g-1 and the maximum adsorption coefficient (Kd) of 0.182 L g-1. The Qe values increased with increasing the initial concentration of SMX, while R and Kd values of SMX decreased. The R values of SMX increased with the increasing dosage of adsorbents, while Qe and Kd values of SMX decreased. These findings will shed new light on the environmentally-friendly and low-cost adsorbent for controlling the antibiotic pollution in marine environment.

Preparation of Hydrated Calcium Silicate Gel and its Adsorption Properties for Cu(II)

2020 ◽  
Vol 993 ◽  
pp. 1445-1449
Author(s):  
Shi Jie Liu ◽  
Su Ping Cui ◽  
Hong Xia Guo ◽  
Ya Li Wang ◽  
Nan Li ◽  
...  
Keyword(s):  
Calcium Silicate ◽  
High Efficiency ◽  
Removal Rate ◽  
Low Cost ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
Adsorption Method ◽  
Hydrated Calcium Silicate ◽  
Adsorption Performance ◽  
Optimum Reaction

Calcium silicate hydrate gel (CSH) was synthesized by calcium acetate and sodium silicate. The structure and morphology of CSH were characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy and Scanning electron microscopy. The adsorption performance of CSH was measured by static adsorption method. The results show that CSH has porous structure and large specific surface area, and the optimum reaction conditions is the reaction temperature of 25°C and calcium-silicon ratio of 1.2. It has the maximum adsorption capacity of more than 150 mg/g and the removal rate of more than 86% with Cu2+. And it shows the excellent adsorption performance, even when the concentration of Cu2+ is less than 200mg/L, the removal rate is above 90%. The research may provide a low-cost and high-efficiency adsorbent.

scholarly journals ADSORPTION OF FLUORIDE USING SIO2 NANOPARTICLES AS ADSORBENT

2020 ◽  
Vol 2 (2) ◽  
pp. 1-9
Author(s):  
Davoud Balarak ◽  
Yousef Mahdavi ◽  
Ali Joghatayi
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Sio2 Nanoparticles ◽  
Second Order ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Initial Concentration ◽  
High Doses

Presence of Fluoride in water is safe and effective when used as directed, but it can be harmful at high doses. In the present paper SiO2 nanoparticles as a adsorbent is used for removal of fluoride from aqueous solution. The effect of various operating parameters such as initial concentration of F-, Contact time, adsorbent dosage and pH were investigated. Equilibrium isotherms were used to identify the possible mechanism of the adsorption process. Maximum adsorption capacity of the SiO2 nanoparticles was 49.95 mg/g at PH=6, contact time 20 min, initial concentration of 25 mg/L, and 25±2 ◦C temperatures, when 99.4% of Fwere removed. The adsorption equilibriums were analyzed by Langmuir and Freundlich isotherm models. It was found that the data fitted to Langmuir (R2=0.992) better than Freundlich (R2=0.943) model. Kinetic analyses were conducted using pseudo first-and second-order models. The regression results showed that the adsorption kinetics was more accurately represented by a pseudo second-order model. These results indicate that SiO2 nanoparticles can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution.

scholarly journals Synthesis of Green Deep Eutectic Solvents for Pretreatment Wheat Straw: Enhance the Solubility of Typical Lignocellulose

2022 ◽  
Vol 14 (2) ◽  
pp. 657
Author(s):  
Zedong Teng ◽  
Liyan Wang ◽  
Bingqian Huang ◽  
Yue Yu ◽  
Jianwei Liu ◽  
...  
Keyword(s):  
Wheat Straw ◽  
Removal Rate ◽  
Low Cost ◽  
Covalent Bond ◽  
Crystallinity Index ◽  
Cost Effective ◽  
Deep Eutectic Solvents ◽  
X Ray Diffraction ◽  
Total Sugar Concentration ◽  
The Cost

Deep eutectic solvents (DESs), a novel and environmentally-friendly solvent, have high potential for biomass pretreatment due to its advantages of low cost, low toxicity, strong solubility, excellent selectivity and biocompatibility. Two types of DES (binary and ternary) were synthesized and characterized, and optimized ternary DES was selected to pretreat wheat straw for enhancement of the solubility of lignocellulose. Moreover, enzymatic hydrolysis was tested to verify the performance of pretreatment. In addition, the changes in surface morphology, structure and crystallinity of wheat straw pretreated by DES were analyzed to reveal the pretreatment mechanism. Experimental results indicated that viscosity exhibited little difference in different types of DESs, and a declining trend as the temperature increases in same DES. The ternary DES pretreatment efficiently enhanced the solubility of typical lignocellulose, with the optimal removal rate of lignin at approximately 69.46%. Furthermore, the total sugar concentration of the residue was about 5.1 times more than that of untreated wheat straw after the pretreated samples were hydrolyzed by the cellulase for 24 h, indicating that DES has the unique ability to selectively extract lignin and hemicellulose from wheat straw while retaining cellulose, and thus enhanced the solubility of lignocellulose. The scanning electron microscope (SEM) observation and X-ray diffraction (XRD) determination showed that the surface of wheat straw suffered from serious erosion and the crystallinity index of wheat straw increased after DES5 pretreatment. Therefore, DES cleaves the covalent bond between lignin and cellulose and hemicellulose, and reduces the intractability of lignin resulting in the lignin dissolution. It suggests that DES can be used as a promising and biocompatible pretreatment way for the cost-effective conversion of lignocellulose biomass into biofuels.

scholarly journals Removal of aqueous organic pollutant by photo-Fenton process using low-cost Fe3O4/zeolite A

2021 ◽  
Vol 947 (1) ◽  
pp. 012013
Author(s):  
Ho Gia Quynh ◽  
Nguyen Anh Kiet ◽  
Huynh Van Thanh ◽  
Ta Man Tue ◽  
Nguyen Thi Truc Phuong ◽  
...  
Keyword(s):  
Textile Industry ◽  
Fenton Reaction ◽  
Low Cost ◽  
Organic Pollutant ◽  
Impregnation Method ◽  
Zeolite A ◽  
X Ray Diffraction ◽  
Initial Concentration ◽  
The Stability ◽  
Uv Lamps

Abstract Degradation of methylene blue (MB) in textile water treatment was investigated by using the photo - Fenton method (mixture of Fe2+ and H2O2 with the UV irradiation) in the presence of nano-sized and low-cost catalyst Fe3O4/Zeolite A. This catalyst was synthesized by impregnation method; furthermore, its photo – catalytic performances and durability in heterogeneous Fenton system were evaluated. Both the structure and the physical chemistry properties of the photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM). The study investigated the influences of different parameters of the MB decolorization efficiency such as initial concentration of peroxide attending the Fenton reaction, amounts of catalyst, pH of the dye solution and comparison of utilization of H2O2 in two cases with and without UV lamps. Under the optimum conditions which is the initial concentration of MB is 50 ppm and pH of dye solution is 3, high efficiencies of degradation were achieved – performance of 92.49%. These results suggest that the low-cost nanostructure catalyst Fe3O4/Zeolite A may be the considerable option because of the durability and the stability in the photo – Fenton reaction for organic wastewater treatment in textile industry.

scholarly journals A Study on the Removal of Copper (II) from Aqueous Solution Using Lime Sand Bricks

2019 ◽  
Vol 9 (4) ◽  
pp. 670 ◽  
Author(s):  
Xiaoran Zhang ◽  
Shimin Guo ◽  
Junfeng Liu ◽  
Ziyang Zhang ◽  
Kaihong Song ◽  
...  
Keyword(s):  
Residence Time ◽  
Removal Rate ◽  
Low Cost ◽  
Column Experiment ◽  
Residual Fraction ◽  
Maximum Adsorption Capacity ◽  
Copper Adsorption ◽  
Exchangeable Fraction ◽  
Pseudo Second Order ◽  
Stormwater Infiltration

Heavy metals such as Cu(II), if ubiquitous in the runoff, can have adverse effects on the environment and human health. Lime sand bricks, as low-cost adsorbents to be potentially applied in stormwater infiltration facilities, were systematically investigated for Cu(II) removal from water using batch and column experiments. In the batch experiment, the adsorption of Cu(II) to bricks reach an equilibrium within 7 h and the kinetic data fits well with the pseudo-second-order model. The sorption isotherm can be described by both the Freundlich and Langmuir model and the maximum adsorption capacity of the bricks is 7 ± 1 mg/g. In the column experiment, the best removal efficiency for Cu(II) was observed at a filler thickness of 20 cm, service time of 12 min with a Cu(II) concentration of 0.5 mg/L. The Cu(II) removal rate increases with the increasing bed depth and residence time. The inlet concentration and residence time had significant effects on the Cu(II) removal analyzed by the Box–Behnken design (BBD). The Adams-Bohart model was in good agreement with the experimental data in representing the breakthrough curve. Copper fractions in the bricks descend in the order of organic matter fraction > Fe-Mn oxides fraction > carbonates fraction > residual fraction > exchangeable fraction, indicating that the lime sand bricks after copper adsorption reduce the long-term ecotoxicity and bioavailability to the environment.

scholarly journals Facile preparation and highly efficient sorption of magnetic composite graphene oxide/Fe3O4/GC for uranium removal

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aili Yang ◽  
Zhijun Wang ◽  
Yukuan Zhu
Keyword(s):  
Aqueous Solution ◽  
Graphene Oxide ◽  
Adsorption Capacity ◽  
High Efficiency ◽  
Removal Rate ◽  
Low Cost ◽  
Hydrothermal Carbonization ◽  
Maximum Adsorption Capacity ◽  
Magnetic Composite ◽  
Order Kinetic

AbstractIn this work, we reported for the first time a novel magnetic composite graphene oxide/Fe3O4/glucose-COOH (GO/Fe3O4/GC) that was facilely prepared from glucose through the hydrothermal carbonization and further combination with graphene oxide (GO). The chemical and structural properties of the samples were investigated. By the batch uranium adsorption experiments, the magnetic composite GO/Fe3O4/GC exhibits an excellent adsorption performance and fast solid–liquid separation for uranium from aqueous solution. GO/Fe3O4/GC (the maximum adsorption capacity (Qm) was 390.70 mg g−1) exhibited excellent adsorption capacity and higher removal rate (> 99%) for U(VI) than those of glucose-COOH (GC) and magnetic GC (MGC). The effect of the coexisting ions, such as Na+, K+, Mg2+, Ca2+, and Al3+, on the U(VI) removal efficiency of GO/Fe3O4/GC was examined. The equilibrium sorption and sorption rate for the as-prepared adsorbents well fit the Langmuir model and pseudo second-order kinetic model, respectively. The thermodynamic parameters (ΔH0 = 11.57 kJ mol−1 and ΔG0 < 0) for GO/Fe3O4/GC indicate that the sorption process of U(VI) was exothermic and spontaneous. Thus, this research provides a facile strategy for the preparation of the magnetic composite with low cost, high efficiency and fast separation for the U(VI) removal from aqueous solution.

scholarly journals Removal of lead (II) from aqueous solutions using rice straw

2017 ◽  
Vol 76 (5) ◽  
pp. 1011-1021 ◽  
Author(s):  
Hayam Amer ◽  
Ahmed El-Gendy ◽  
Salah El-Haggar
Keyword(s):  
Rice Straw ◽  
Low Cost ◽  
Research Work ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Optimum Conditions ◽  
Optimum Parameters ◽  
Removal Of Heavy Metals ◽  
Maximum Removal

Lead (Pb2+) is a heavy metal which is utilized in several industries and can have severe impact on the environment and human health. Research work has been carried out lately on the feasibility of using various low cost materials in the removal of heavy metals from wastewater. In this study, the feasibility of utilizing raw rice straw for removal of Pb2+ from water through biosorption was investigated using batch equilibrium experiments. The effect of several operating parameters on the removal of Pb2+ using rice straw was studied, revealing the optimum parameters at an initial Pb2+ concentration of 40 mg/l were: 30 min contact time at a pH of 5.5, particle size 75–150 μm and a dose of 4 g/l. A maximum removal of 94% was achieved under optimum conditions. Langmuir and Freundlich isotherm models were used for the evaluation of the equilibrium experimental data. The maximum adsorption capacity of rice straw calculated using the Langmuir isotherm was 42.55 mg/g.

scholarly journals REMOVAL OF A CHEMICAL DYE FROM WASTEWATER USING LOW COST AGRO-BASED ADSORBENTS: CONTINUOUS ADSORBERS

2019 ◽  
Vol 11 (2) ◽  
pp. 229-245
Author(s):  
Hatem Asal Gzar ◽  
Noor Qassim Sabri
Keyword(s):  
Activated Carbon ◽  
Removal Efficiency ◽  
Flow Rate ◽  
Textile Industry ◽  
Ph Value ◽  
Low Cost ◽  
Continuous System ◽  
Initial Concentration ◽  
Chemically Treated ◽  
Maximum Removal

Natural materials that are readily available in large amounts in nature and easily accessible may be used as low cost additives. The aim of this study is to measure the susceptibility of these locally available materials, conocarpus plant, to improve the quality of wastewater discharged from textile industry. In addition to conocarpus- without chemically treated, conocarpus- chemically treated, carbonized conocarpus and activated carbon were used as adsorbents in order to make a comparison, and to test which one of the four types give the best efficiency for removing dye. The ability of adsorbents to adsorb dye was studied using continuous system; studied parameters were effect of flow rate, bed depth, and initial concentration. The experimental results showed that maximum removal efficiency of conocarpus - without chemically treated was found to be 90% after 75 min at flow rate 20 l/h, pH value 3 , bed depth 5cm and initial concentration 40 mg/l. The maximum removal efficiency for conocarpus- chemically treated was up to 83.75% after 15 min at flow rate 10 l/h, pH value 3, bed depth 10 cm and initial dye concentration 40 mg/l. The maximum removal efficiency for carbonized conocarpus was up to 99.67% after 15 min at flow rate 10 l/h, pH value 3, bed depth 10 cm and initial dye concentration 40 mg/l. For activated carbon the maximum removal efficiency was found to be 99.75% after 15 min at flow rate 10 l/h, pH value 3, bed depth 10cm and initial dye concentration 40 mg/l.

scholarly journals Fabrication and Evaluation of Bimetallic Materials for Removal of Cr6+

2022 ◽  
Vol 2160 (1) ◽  
pp. 012011
Author(s):  
Tingting Wang ◽  
Zhiyong Han ◽  
Xiaobin Lv
Keyword(s):  
High Performance ◽  
Ph Value ◽  
Removal Rate ◽  
Low Cost ◽  
Initial Concentration ◽  
Effective Removal ◽  
Removal Of Heavy Metals ◽  
Adsorption Technology ◽  
Bimetallic Materials ◽  
Heavy Metals Ions

Abstract Adsorption technology is an effective way for removal of heavy metals ions and other organic pollutants in water treatment. In recent years, bimetallic adsorbents with high performance and low cost have attracted more and more attention. In this study, nano zero valent iron was prepared. On this basis, Fe/Cu Bimetallic materials were prepared. The effects of Cu conversion, initial concentration, time, and pH value on Cr6+ removal rate and amount were systematically tested. The results show that under the conditions of initial concentration (50mg/L), time (60min) and pH (3), the Fe/Cu material with copper conversion of 3% has the best effect on the removal of Cr6+ in wastewater. Thus, this study is expected to provide important reference data for the effective removal of Cr6+ in water.

scholarly journals Modeling and Optimizing of NH4+ Removal from Stormwater by Coal-Based Granular Activated Carbon Using RSM and ANN Coupled with GA

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 608
Author(s):  
Aixin Yu ◽  
Yuankun Liu ◽  
Xing Li ◽  
Yanling Yang ◽  
Zhiwei Zhou ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Contact Time ◽  
Adsorption Process ◽  
Removal Rate ◽  
Granular Activated Carbon ◽  
Operating Conditions ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Initial Concentration ◽  
Rsm Optimization

As a key parameter in the adsorption process, removal rate is not available under most operating conditions due to the time and cost of experimental testing. To address this issue, evaluation of the efficiency of NH4+ removal from stormwater by coal-based granular activated carbon (CB-GAC), a novel approach, the response surface methodology (RSM), back-propagation artificial neural network (BP-ANN) coupled with genetic algorithm (GA), has been applied in this research. The sorption process was modeled based on Box-Behnben design (BBD) RSM method for independent variables: Contact time, initial concentration, temperature, and pH; suggesting a quadratic polynomial model with p-value < 0.001, R2 = 0.9762. The BP-ANN with a structure of 4-8-1 gave the best performance. Compared with the BBD-RSM model, the BP-ANN model indicated better prediction of the response with R2 = 0.9959. The weights derived from BP-ANN was further analyzed by Garson equation, and the results showed that the order of the variables’ effectiveness is as follow: Contact time (31.23%) > pH (24.68%) > temperature (22.93%) > initial concentration (21.16%). The process parameters were optimized via RSM optimization tools and GA. The results of validation experiments showed that the optimization results of GA-ANN are more accurate than BBD-RSM, with contact time = 899.41 min, initial concentration = 17.35 mg/L, temperature = 15 °C, pH = 6.98, NH4+ removal rate = 63.74%, and relative error = 0.87%. Furthermore, the CB-GAC has been characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The isotherm and kinetic studies of the adsorption process illustrated that adsorption of NH4+ onto CB-GAC corresponded Langmuir isotherm and pseudo-second-order kinetic models. The calculated maximum adsorption capacity was 0.2821 mg/g.

Sign in / Sign up

Export Citation Format

Share Document