Modeling and Optimization of Biochar Based Adsorbent Derived from Kenaf Using Response Surface Methodology on Adsorption of Cd2+

Cadmium is one of the most hazardous metals in the environment, even when present at very low concentrations. This study reports the systematic development of Kenaf fiber biochar as an adsorbent for the removal of cadmium (Cd) (II) ions from water. The adsorbent development was aided by an optimization tool. Activated biochar was prepared using the physicochemical activation method, consisting of pre-impregnation with NaOH and nitrogen (N2) pyrolysis. The influence of the preparation parameters—namely, chemical impregnation (NaOH: KF), pyrolysis temperature, and pyrolysis time on biochar yield, removal rate, and the adsorption capacity of Cd (II) ions—was investigated. From the experimental data, some quadratic correlation models were developed according to the central composite design. All models demonstrated a good fit with the experimental data. The experimental results revealed that the pyrolysis temperature and heating time were the main factors that affected the yield of biochar and had a positive effect on the Cd (II) ions’ removal rate and adsorption capacity. The impregnation ratio also showed a positive effect on the specific surface area of the biochar, removal rate, and adsorption capacity of cadmium, with a negligible effect on the biochar yield. The optimal biochar-based adsorbent was obtained under the following conditions: 550 °C of pyrolysis temperature, 180 min of heating time, and a 1:1 NaOH impregnation ratio. The optimum adsorbent showed 28.60% biochar yield, 69.82% Cd (II) ions removal, 23.48 mg/g of adsorption capacity, and 160.44 m2/g of biochar-specific area.

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Thermodynamic Properties of Modified Sepiolite Phosphorus Removal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.234 ◽

2013 ◽

Vol 726-731 ◽

pp. 234-238

Author(s):

Wen Quan

Keyword(s):

Experimental Data ◽

Thermodynamic Properties ◽

Adsorption Capacity ◽

Phosphorus Removal ◽

Theoretical Foundation ◽

Removal Rate ◽

Adsorption Properties ◽

Phosphorus Adsorption ◽

Depth Study ◽

Adsorption Amount

this thesis makes an in-depth study on the adsorption properties of modified sepiolite to phosphorus, and confirms how the factors such as, phosphorus wastewater flow, phosphorus removal agent dosage, temperature, additives and other factors effect on the phosphorus adsorption thermodynamic equilibrium of modified sepiolite. With the increase of phosphorus removal agent of modified sepiolite, adsorption capacity of modified sepiolite phosphorus removal to PO43- ions in wastewater decreases; the removal rate increases with the increase removal agent; improving the acid modified temperature favors the adsorption of compound phosphorus removal to sepiolite; adsorption amount increases with the calcination temperature of sepiolite. This thesis describes the adsorption capacity of the modified sepiolite to phosphorus changes with temperature. According to the experimental data, adsorption isotherms at different temperature are presented in this thesis. And a theoretical foundation is provided for the industrial application of modified sepiolite phosphorus removal.

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Optimization of biochar preparation from the stem of Eichhornia crassipes using response surface methodology on adsorption of Cd2+

Scientific Reports ◽

10.1038/s41598-019-54105-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

Runjuan Zhou ◽

Ming Zhang ◽

Jinhong Zhou ◽

Jinpeng Wang

Keyword(s):

Response Surface Methodology ◽

Adsorption Capacity ◽

Response Surface ◽

Heating Rate ◽

Eichhornia Crassipes ◽

Heating Temperature ◽

Removal Rate ◽

Heating Time ◽

Optimal Conditions ◽

Preparation Conditions

AbstractIn this study, preparation of Eichhornia crassipes stem biochar (ECSBC) was optimized and applied for the removal of Cd2+ from aqueous solution. To obtain the best adsorption capacity of ECSBC, the response surface methodology (RSM) was used to optimize the preparation conditions of ECSBC (OECSBC). The interactions among heating time (X1), heating temperature (X2) and heating rate (X3) were designed by Box-Behnken Design (BBD) experiments. The software gave seventeen runs experiment within the optimal conditions towards two response variables (removal rate and adsorption capacity for Cd2+). The results showed that the mathematical model could fit the experimental data very well and the significance of the influence factors followed the order as heating temperature (X2) > heating rate (X3) > heating time (X1), and the influence of interaction term is: X1 and X2 (heating time and heating temperature) > X2 and X3 (heating temperature and heating rate) > X1 and X3 (heating time and heating rate). Based on the analysis of variance and the method of numerical expected function, the optimal conditions were heating time of 2.42 h, heating temperature of 393 °C, and heating rate of 15.56 °C/min. Under the optimum conditions, the predicted the maximum removal rate and adsorption capacity were 85.2724% and 21.168 mg/g, respectively, and the experimental value of removal rate and adsorption capacity for Cd2+ were 80.70% and 20.175 mg/g, respectively, the deviation from the predicted value were 5.36% and 4.69%. The results confirmed that the RSM can optimize the preparation conditions of ECSBC, and the adsorption capacity of OECSB was improved.

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Utilization of Waste of Enzymes Biomass as Biosorbent for the Removal of Dyes from Aqueous Solution in Batch and Fluidized Bed Column

Revista de Chimie ◽

10.37358/rc.20.1.7804 ◽

2020 ◽

Vol 71 (1) ◽

pp. 1-12

Author(s):

Salman H. Abbas ◽

Younis M. Younis ◽

Mohammed K. Hussain ◽

Firas Hashim Kamar ◽

Gheorghe Nechifor ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solution ◽

Particle Size ◽

Adsorption Capacity ◽

Fluidized Bed ◽

Flow Rate ◽

Fungal Biomass ◽

Solution Flow Rate ◽

Maximum Adsorption Capacity ◽

Solution Flow

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.

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Stormwater Runoff Treatment Using Pervious Concrete Modified with Various Nanomaterials: A Comprehensive Review

Sustainability ◽

10.3390/su13158552 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8552

Author(s):

Vahid Alimohammadi ◽

Mehdi Maghfouri ◽

Delaram Nourmohammadi ◽

Pejman Azarsa ◽

Rishi Gupta ◽

...

Keyword(s):

Heavy Metals ◽

Compressive Strength ◽

Adsorption Capacity ◽

Removal Rate ◽

Stormwater Runoff ◽

Infiltration Rate ◽

Stormwater Treatment ◽

Adsorption Mechanisms ◽

Wide Range ◽

Adsorption Processes

Clean water is a vital need for all living creatures during their lifespan. However, contaminated stormwater is a major issue around the globe. A wide range of contaminants, including heavy metals, organic and inorganic impurities, has been discovered in stormwater. Some commonly utilized methods, such as biological, physical and chemical procedures, have been considered to overcome these issues. However, these current approaches result in moderate to low contaminant removal efficiencies for certain classes of contaminants. Of late, filtration and adsorption processes have become more featured in permeable concretes (PCs) for the treatment of stormwater. As nanoparticles have vast potential and unique characterizations, such as a higher surface area to cure polluted stormwater, employing them to improve permeable concretes’ capabilities in stormwater treatment systems is an effective way to increase filtration and adsorption mechanisms. The present study reviews the removal rate of different stormwater contaminants such as heavy metals, organic and other pollutants using nanoparticle-improved PC. The application of different kinds of nanomaterials in PC as porous media to investigate their influences on the properties of PC, including the permeability rate, compressive strength, adsorption capacity and mix design of such concrete, was also studied. The findings of this review show that different types of nanomaterials improve the removal efficiency, compressive strength and adsorption capacity and decrease the infiltration rate of PC during the stormwater treatment process. With regard to the lack of comprehensive investigation concerning the use of nanomaterials in PC to treat polluted stormwater runoff, this study reviews 242 published articles on the removal rate of different stormwater contaminants by using PC improved with nanoparticles.

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Hydrothermal Synthesis of Sodalite-Type N-A-S-H from Fly Ash to Remove Ammonium and Phosphorus from Water

Materials ◽

10.3390/ma14112741 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2741

Author(s):

Pengcheng Lv ◽

Ruihong Meng ◽

Zhongyang Mao ◽

Min Deng

Keyword(s):

Fly Ash ◽

Adsorption Capacity ◽

Removal Rate ◽

Kinetic Studies ◽

Solute Concentration ◽

Raw Material ◽

Sodium Aluminosilicate ◽

Equilibrium Data ◽

One Step ◽

Ft Ir

In this study, the hydrated sodium aluminosilicate material was synthesized by one-step hydrothermal alkaline desilication using fly ash (FA) as raw material. The synthesized materials were characterized by XRD, XRF, FT-IR and SEM. The characterization results showed that the alkali-soluble desilication successfully had synthesized the sodium aluminosilicate crystalline (N-A-S-H) phase of sodalite-type (SOD), and the modified material had good ionic affinity and adsorption capacity. In order to figure out the suitability of SOD as an adsorbent for the removal of ammonium and phosphorus from wastewater, the effects of material dosing, contact time, ambient pH and initial solute concentration on the simultaneous removal of ammonium and phosphorus are investigated by intermittent adsorption tests. Under the optimal adsorption conditions, the removal rate of ammonium was 73.3%, the removal rate of phosphate was 85.8% and the unit adsorption capacity reached 9.15 mg/L and 2.14 mg/L, respectively. Adsorption kinetic studies showed that the adsorption of ammonium and phosphorus by SOD was consistent with a quasi-secondary kinetic model. The adsorption isotherm analysis showed that the equilibrium data were in good agreement with the Langmuir and Freundlich model. According to thermodynamic calculations, the adsorption of ammonium and phosphorus was found to be a heat-absorbing and spontaneous process. Therefore, the preparation of SOD by modified FA has good adsorption properties as adsorbent and has excellent potential for application in the removal of contaminants from wastewater.

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Kinetics and thermodynamic properties related to the drying of 'Cabacinha' pepper fruits

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v20n2p174-180 ◽

2016 ◽

Vol 20 (2) ◽

pp. 174-180 ◽

Cited By ~ 8

Author(s):

Hellismar W. da Silva ◽

Renato S. Rodovalho ◽

Marya F. Velasco ◽

Camila F. Silva ◽

Luís S. R. Vale

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Free Energy ◽

Thermodynamic Properties ◽

Gibbs Free Energy ◽

Removal Rate ◽

Effective Diffusion ◽

Drying Time ◽

Three Samples ◽

Different Temperatures

ABSTRACT The objective of this study was to determine and model the drying kinetics of 'Cabacinha' pepper fruits at different temperatures of the drying air, as well as obtain the thermodynamic properties involved in the drying process of the product. Drying was carried out under controlled conductions of temperature (60, 70, 80, 90 and 100 °C) using three samples of 130 g of fruit, which were weighed periodically until constant mass. The experimental data were adjusted to different mathematical models often used in the representation of fruit drying. Effective diffusion coefficients, calculated from the mathematical model of liquid diffusion, were used to obtain activation energy, enthalpy, entropy and Gibbs free energy. The Midilli model showed the best fit to the experimental data of drying of 'Cabacinha' pepper fruits. The increase in drying temperature promoted an increase in water removal rate, effective diffusion coefficient and Gibbs free energy, besides a reduction in fruit drying time and in the values of entropy and enthalpy. The activation energy for the drying of pepper fruits was 36.09 kJ mol-1.

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Three novel biosorbents based on modified peanut shells for direct red 80 removal: parameter optimization, process kinetics and equilibrium

RSC Advances ◽

10.1039/c5ra14953c ◽

2015 ◽

Vol 5 (91) ◽

pp. 74467-74485 ◽

Cited By ~ 7

Author(s):

Lei Zhang ◽

Zhengjun Cheng ◽

Xiao Guo ◽

Xiaohui Jiang ◽

Tian Li

Keyword(s):

Experimental Data ◽

Adsorption Capacity ◽

Parameter Optimization ◽

Optimization Process ◽

Process Kinetics ◽

Peanut Shells

In this study, we report three novel biosorbents. Many aspects of the title process are presented. The results indicate that the models could be well described experimental data and hence may play a role in predication of the adsorption capacity.

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HPHT synthesis and enhanced TE performance of Te and Sn/Se elements binary-doped CoSb3

Functional Materials Letters ◽

10.1142/s1793604718501059 ◽

2019 ◽

Vol 12 (01) ◽

pp. 1850105 ◽

Cited By ~ 1

Author(s):

Hairui Sun ◽

Pin Lv ◽

Chao Wang ◽

Yunxian Liu ◽

Xiaopeng Jia ◽

...

Keyword(s):

Experimental Data ◽

Thermal Conductivity ◽

High Pressure ◽

High Temperature ◽

Seebeck Coefficient ◽

Grain Boundaries ◽

Preparation Methods ◽

Synthesis Time ◽

Lattice Disorder ◽

Positive Effect

A series of binary-doped CoSb3 with Te and Se/Sn bulk compounds Co4Sb[Formula: see text]TexSny/Sey ([Formula: see text] and 0.6, [Formula: see text] and 0.3), have been successfully prepared via a simple high pressure and high-temperature (HPHT) method. And, the influence of the doping elements on the microstructure of the samples synthesized under diverse pressures and the corresponding TE performance were studied in detail. Comparing with other preparation methods, the synthesis time of HPHT was acutely shortened. The obtained samples contain more grain boundaries, lattice disorder, dislocations and the possible “nanodot”, which have positive effect on reducing thermal conductivity. The experimental data indicate that the absolute values of Seebeck coefficient increases with pressure. What’s more, the thermal conductivities show a monotone decreasing trend as the synthesis pressure rises. The minimum value obtained is 1.93[Formula: see text]Wm[Formula: see text]K[Formula: see text] at normal temperature for Co4Sb[Formula: see text]Te[Formula: see text]Se[Formula: see text] prepared under 3[Formula: see text]GPa.

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Synthesis and characterization of pecan nutshell-based adsorbent with high specific area and high methylene blue adsorption capacity

Journal of Molecular Liquids ◽

10.1016/j.molliq.2018.12.010 ◽

2019 ◽

Vol 276 ◽

pp. 570-576 ◽

Cited By ~ 5

Author(s):

Hugo H.C. Lima ◽

Rogério S. Maniezzo ◽

Maria E.G. Llop ◽

Vincente L. Kupfer ◽

Pedro A. Arroyo ◽

...

Keyword(s):

Methylene Blue ◽

Adsorption Capacity ◽

Specific Area ◽

Synthesis And Characterization ◽

Methylene Blue Adsorption ◽

Pecan Nutshell ◽

High Specific Area

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Preparation of crosslinked chitosan magnetic membrane for cations sorption from aqueous solution

Water Science & Technology ◽

10.2166/wst.2017.078 ◽

2017 ◽

Vol 75 (9) ◽

pp. 2034-2046 ◽

Cited By ~ 9

Author(s):

Adnan Khan ◽

Samina Begum ◽

Nauman Ali ◽

Sabir Khan ◽

Sajjad Hussain ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solution ◽

Adsorption Capacity ◽

Magnetic Particles ◽

Isotherm Models ◽

Chitosan Membrane ◽

Dilute Aqueous Solution ◽

Chitosan Membranes ◽

The Fourier Transform ◽

Time Required

A chitosan magnetic membrane was prepared in order to confer magnetic properties to the membrane, which could be used for the removal of cations from aqueous solution. The crosslinked magnetic membrane was compared with pristine chitosan membrane in term of stability, morphology and cation adsorption capacity. The fabricated magnetic materials are thermally stable as shown by thermogravimetric curves. The membrane containing nickel magnetic particles (CHNiF-G) shows high thermal stability compared to the other membranes. The Fourier transform infrared spectroscopy showed successful preparation of chitosan magnetic membrane. Scanning electron microscopy micrographs showed the rough surface of the membrane with increased porosity. The prepared chitosan membranes were applied to cations of copper, nickel and lead in dilute aqueous solution. The chitosan membrane showed the following adsorption order for metallic cations: Cu2+ > Ni2+ > Pb2+, while CHNiF-G showed higher capacity, 3.51 mmol g−1 for copper, reflecting the improvement in adsorption capacity, since the amount of copper on pristine chitosan gave 1.40 mmol g−1. The time required for adsorption to reach to the equilibrium was 6 h for the selected cations using different chitosan membranes. The kinetic study showed that adsorption followed pseudo-second order kinetics. The most commonly used isotherm models, Freundlich, Langmuir and Temkin, were applied to experimental data using linear regression technique. However, The Temkin model fits better to experimental data.

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