scholarly journals Influence of Calcination conditions on the Adsorption Properties of the Wasted Sea Shell to the Dibutyl phthalate

2021 ◽  
Keyword(s):  
Specific Surface ◽  
Dibutyl Phthalate ◽  
Freundlich Isotherm ◽  
Unit Cell ◽  
Calcination Time ◽  
Surface Areas ◽  
Unit Cell Size ◽  
Different Temperatures ◽  
Time Extension ◽  
Adsorption Capability

<p>The calcined clam seashell powders were applied as adsorbent to adsorb Dibutyl phthalate (DBP), from an aqueous solution. The influence of calcination conditions including temperature and time on its adsorption capability to DBP was investigated. The shell powders calcined at 500 oC had the best adsorption capability. As the calcination time extending under different temperatures, the adsorption capabilities showed the same tendency and reached peak values at the calcination time of 10mins. Calcination time extension also led to the increase of crystal unit cell Sizes of CaCO3 inside the clam seashells at the first 10mins and then decreased to the stable value, Correspondingly, the calcined shell specific surface areas decreased firstly to the minimum at 10mins and then gradually increased, as the calcination process lasting at 500oC. The maximum adsorption capability as 1.237mg/g, the lowest specific surface area as 14.2m2/g, and the largest unit cell size as 60.7nm of CaCO3 simultaneously exhibited at the calcination time of 10mins. The Freundlich isotherm model and the pseudo-second-order-kinetics model were appropriate for describing the adsorption isotherm and kinetics of DBP at 30oC, respectively. It is inferred that the interaction between calcined shell and DBP is chemical adsorption.</p>

scholarly journals Preparation Method of Co3O4Nanoparticles Using Degreasing Cotton and Their Electrochemical Performances in Supercapacitors

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Hongyan Xu ◽  
Libo Gao ◽  
Qiang Zhang ◽  
Junyang Li ◽  
Jiangtao Diwu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Specific Surface ◽  
Photoelectron Spectroscopy ◽  
Nitrogen Adsorption ◽  
Electrochemical Performances ◽  
X Ray ◽  
Surface Areas ◽  
Synthetic Strategy ◽  
Different Temperatures ◽  
Specific Surface Areas

Co3O4nanoparticles were fabricated by a novel, facile, and environment-friendly carbon-assisted method using degreasing cotton. Structural and morphological characterizations were performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The component of the sample obtained at different temperatures was measured by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Nitrogen adsorption and desorption isotherms were utilized to reveal the specific surface areas. The formation mechanism of Co3O4nanoparticles was also proposed, demonstrating that the additive degreasing cotton played an indispensable role in the process of synthesizing the sample. The resultant Co3O4sample calcined at 600°C exhibited superior electrochemical performance with better specific capacitance and long-term cycling life, due to its high specific surface areas and pores structures. Additionally, it has been proved that this facile synthetic strategy can be extended to produce other metal oxide materials (e.g., Fe3O4). As a consequence, the carbon-assisted method using degreasing cotton accompanied a promising prospect for practical application.

Adsorption of Dyes from Wastewater onto Cross-Linked Chitosan Beads

2010 ◽  
Vol 156-157 ◽  
pp. 1404-1409 ◽  
Author(s):  
Xiao Qing Guo ◽  
Li Jun Qu ◽  
Guo Jun Han ◽  
Ya Ning Sun
Keyword(s):  
Freundlich Isotherm ◽  
Dyeing Wastewater ◽  
High Adsorption ◽  
Chitosan Beads ◽  
Freundlich Isotherms ◽  
Equilibrium Data ◽  
Different Temperatures ◽  
Ft Ir ◽  
High Adsorption Capacity ◽  
Adsorption Capability

Adsorption of dye from dyeing wastewater had been investigated using cross-linked chitosan beads as an adsorbent. The chitosan adsorbent was characterized by SEM, FT-IR and porosity [P]. Various parameters such as concentration of adsorbent (0.5 g/200mL to 2.5 g/200mL), pH (3-11), initial concentration of dye (50-250mg/L) and temperature (15-45 ) of adsorbate were studied. Langmuir and Freundlich isotherms were used to analyze the equilibrium data at different temperatures. Freundlich isotherm showed better correlation coefficient than the other models at all temperatures studied. The cross-linked chitosan adsorbent exhibits a high adsorption capacity to remove dye. And the adsorbent still has good adsorption capability after being reclaimed for 6 times. This study indicates that cross-linked chitosan is a promising adsorbent for removing dye from dyeing wastewater.

scholarly journals Adsorptive removal of Pb(II) ions from aqueous solution by activated carbon prepared from cabbage waste

2020 ◽  
Vol 8 ◽  
pp. 1-10
Author(s):  
Keshav Raj Paneru ◽  
Binay Kumar Jha
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Specific Surface ◽  
Metal Ion ◽  
Activated Carbons ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Adsorption Method ◽  
Surface Areas

The present study deals with the adsorption of Pb(II) from an aqueous solution on activated carbon obtained from cabbage waste. Such activated carbon was prepared by pyrolysis of cabbage waste powder at 700 °C for 1 hour in three different atmospheres, namely open air (CWAC-O), nitrogen (CWAC-N) and nitrogen with steam (CWWAC-NW). The specific surface areas of thus obtained three types of activated carbons were determined by methylene blue adsorption method and found for CWAC-O, CWAC-N and CWAC-NW as 59, 169 and 310 m2/g, respectively. Due to the highest specific surface area of CWAC-NW, the adsorption of Pb(II) experiments was performed onto CWAC-NW only. The influence of various parameters like pH, adsorbent dose, contact time and different initial concentrations of metal ion on adsorption of Pb(II) were studied. The equilibrium data for adsorption was analyzed by using Langmuir and Freundlich isotherm models. The Langmuir adsorption isotherm model was found the best fit for the experimental data. The maximum adsorption capacity was 54.945 mg/g. Kinetics results were described by a pseudo second order model with the rate constant value 0.055 g/(mg∙min). The main mechanism of the adsorption process was physicochemical adsorption and was not solely intraparticle diffusion.

scholarly journals Allanite at high temperature: effect of REE on the thermal behaviour of epidote-group minerals

2021 ◽  
Vol 48 (9) ◽  
Author(s):  
G. Diego Gatta ◽  
Francesco Pagliaro ◽  
Paolo Lotti ◽  
Alessandro Guastoni ◽  
Laura Cañadillas-Delgado ◽  
...  
Keyword(s):  
Cell Volume ◽  
Thermal Behaviour ◽  
Unit Cell Volume ◽  
Unit Cell ◽  
Atomic Scale ◽  
Elastic Behaviour ◽  
Positive Trend ◽  
Cell Parameters ◽  
Thermal Anisotropy ◽  
Different Temperatures

AbstractThe thermal behaviour of a natural allanite-(Ce) has been investigated up to 1073 K (at room pressure) by means of in situ synchrotron powder X-ray diffraction and single-crystal neutron diffraction. Allanite preserves its crystallinity up to 1073 K. However, up to 700 K, the thermal behaviour along the three principal crystallographic axes, of the monoclinic β angle and of the unit-cell volume follow monotonically increasing trends, which are almost linear. At T > 700–800 K, a drastic change takes place: an inversion of the trend is observed along the a and b axes (more pronounced along b) and for the monoclinic β angle; in contrast, an anomalous increase of the expansion is observed along the c axis, which controls the positive trend experienced by the unit-cell volume at T > 700–800 K. Data collected back to room T, after the HT experiments, show unit-cell parameters significantly different with respect to those previously measured at 293 K: allanite responds with an ideal elastic behaviour up to 700 K, and at T > 700–800 K its behaviour deviates from the elasticity field. The thermo-elastic behaviour up to 700 K was modelled with a modified Holland–Powell EoS; for the unit-cell volume, we obtained the following parameters: VT0 = 467.33(6) Å3 and αT0(V) = 2.8(3) × 10–5 K−1. The thermal anisotropy, derived on the basis of the axial expansion along the three main crystallographic directions, is the following: αT0(a):αT0(b):αT0(c) = 1.08:1:1.36. The T-induced mechanisms, at the atomic scale, are described on the basis of the neutron structure refinements at different temperatures. Evidence of dehydroxylation effect at T ≥ 848 K are reported. A comparison between the thermal behaviour of allanite, epidote and clinozoisite is carried out.

scholarly journals Fabrication and Compressive Behavior of a Micro-Lattice Composite by High Resolution DLP Stereolithography

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 785
Author(s):  
Chow Shing Shin ◽  
Yu Chia Chang
Keyword(s):  
High Resolution ◽  
Lattice Structure ◽  
Low Cost ◽  
Hierarchical Structures ◽  
Dip Coating ◽  
Unit Cell ◽  
Digital Light Processing ◽  
Unit Cell Size ◽  
Wide Range ◽  
And Performance

Lattice structures are superior to stochastic foams in mechanical properties and are finding increasing applications. Their properties can be tailored in a wide range through adjusting the design and dimensions of the unit cell, changing the constituent materials as well as forming into hierarchical structures. In order to achieve more levels of hierarchy, the dimensions of the fundamental lattice have to be small enough. Although lattice size of several microns can be fabricated using the two-photon polymerization technique, sophisticated and costly equipment is required. To balance cost and performance, a low-cost high resolution micro-stereolithographic system has been developed in this work based on a commercial digital light processing (DLP) projector. Unit cell lengths as small as 100 μm have been successfully fabricated. Decreasing the unit cell size from 150 to 100 μm increased the compressive stiffness by 26%. Different pretreatments to facilitate the electroless plating of nickel on the lattice structure have been attempted. A pretreatment of dip coating in a graphene suspension is the most successful and increased the strength and stiffness by 5.3 and 3.6 times, respectively. Even a very light and incomplete nickel plating in the interior has increase the structural stiffness and strength by more than twofold.

Preparation of Sands Modified by Aluminous Salt and its Adsorption Capability of CD2+

2011 ◽  
Vol 130-134 ◽  
pp. 856-859
Author(s):  
Chun Sheng Ding ◽  
Yang Ping Fu ◽  
Qian Fen Zhu ◽  
Jing Fu
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Influencing Factors ◽  
Removal Efficiency ◽  
Specific Surface Area ◽  
Quartz Sand ◽  
Ph Value ◽  
Alkaline Condition ◽  
Initial Concentration ◽  
Adsorption Capability

In this experiment quartz sand was chosen as a carrier to be coated by aluminous salt under alkaline condition, and then the specific surface area was tested, and the adsorption capability and Cd2+ removal influencing factors of modified sand were studied. The investigation results showed that the specific surface area of modified sand was 75.244m2/g which was 9.38 times of that of original sand; the removal efficiency of Cd2+ by aluminous salt modified sand reached 59% contrast to 39% of original sand with pH 7.00. It was also found that the removal efficiency of Cd2+ by the aluminous salt modified sand was reduced with the increase of initial concentration of Cd2+ solution, and was enhanced with the increase of pH value, the Cd2+ removal efficiency was almost 71% with pH 9.0.

scholarly journals Effect of calcination temperature and calcination time on the kaolinite/tio2 composite for photocatalytic reduction of CO2

2012 ◽  
Vol 58 (4) ◽  
pp. 10-22 ◽  
Author(s):  
Martin Reli ◽  
Kamila Kočí ◽  
Vlastimil Matějka ◽  
Pavel Kovář ◽  
Lucie Obalová
Keyword(s):  
Crystallite Size ◽  
Physical Adsorption ◽  
Photocatalytic Reduction ◽  
Thermal Hydrolysis ◽  
Calcination Time ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Titanyl Sulphate ◽  
Reduction Of Co2 ◽  
Hydrolysis Of

Abstract The kaolinite/TiO2 composite (60 wt% of TiO2) was prepared by thermal hydrolysis of a raw kaolin suspension in titanyl sulphate and calcined at different temperatures (600, 650 and 700°C) and for different times (1, 2 and 3 h). The obtained samples were characterized by XRPD, N2 physical adsorption and SEM, and tested for photocatalytic reduction of CO2. The different calcination conditions did not influence TiO2 phase composition, only slightly changed the specific surface area, and significantly affected crystallite size of kaolinite/TiO2 composite. A higher temperature and longer duration of calcination lead to higher crystallinity of the powder. The photocatalytic results showed that the crystallite size determined the efficiency of kaolinite/TiO2 photocatalysts.

scholarly journals Ultrafine porous boron nitride nanofibers synthesized via a freeze-drying and pyrolysis process and their adsorption properties

RSC Advances ◽  
2016 ◽  
Vol 6 (2) ◽  
pp. 1253-1259 ◽  
Author(s):  
Jing Lin ◽  
Lulu Xu ◽  
Yang Huang ◽  
Jie Li ◽  
Weijia Wang ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Specific Surface ◽  
Freeze Drying ◽  
Adsorption Properties ◽  
Pyrolysis Process ◽  
Surface Areas ◽  
Aspect Ratios ◽  
Large Pore ◽  
Specific Surface Areas

Ultrafine porous boron nitride nanofibers with high aspect ratios, high specific surface areas and large pore volumes has been synthesized in large quantity via a freeze-drying and post pyrolysis process.

scholarly journals Experimental Investigation of Coal Dust Wettability Based on Surface Contact Angle

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Gang Zhou ◽  
Han Qiu ◽  
Qi Zhang ◽  
Mao Xu ◽  
Jiayuan Wang ◽  
...  
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Specific Surface ◽  
Coal Dust ◽  
Single Point ◽  
Contact Angles ◽  
Critical Surface ◽  
Volume Percentage ◽  
Surface Areas ◽  
Specific Surface Areas

Wettability is one of the key chemical properties of coal dust, which is very important to dedusting. In this paper, the theory of liquid wetting solid was presented firstly; then, taking the gas coal of Xinglongzhuang coal mine in China as an example, by determination of critical surface tension of coal piece, it can be concluded that only when the surface tension of surfactant solution is less than 45 mN/m can the coal sample be fully wetted. Due to the effect of particle dispersity, compared with the contact angle of milled coal particle, not all the contact angles of screened coal powder with different sizes have a tendency to increase. Furthermore, by the experiments of coal samples’ specific surface areas and porosities, it can be achieved that the volume of single-point total pore decreases with the gradual decreasing of coal’s porosity, while the ultramicropores’ dispersities and multipoint BET specific surface areas increase. Besides, by a series of contact angle experiments with different surfactants, it can be found that with the increasing of porosity and the decreasing of volume percentage of ultramicropore, the contact angle tends to reduce gradually and the coal dust is much easier to get wetted.

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