scholarly journals Sorption of Ga (III) on Flexible Open Cell Polyurethane Foam of Polyether Type Impregnated with Tri-N-Buthyl Phospate

2007 ◽  
Vol 2 (1) ◽  
pp. 51-57
Author(s):  
Lavinia Tofan ◽  
Doina Bilba ◽  
Carmen Paduraru ◽  
Ovidiu Toma
Keyword(s):  
Thermodynamic Parameters ◽  
Polyurethane Foam ◽  
Contact Time ◽  
Solution Temperature ◽  
Open Cell ◽  
Langmuir Isotherms ◽  
Batch Sorption ◽  
Solution Acidity

The obtained results concerning the Ga (III) ion retention on flexible open cell polyurethane foam of polyether type pretreated with tri-n-butyl phosphate are presented. The influence of solution acidity, phases contact time, Ga (III) concentration and solution temperature have been investigated. The parameters of Ga (III) batch sorption have been optimized. On the basis of Langmuir isotherms, the sorption constants and the thermodynamic parameters, ∆G, ∆Η and ∆S have been calculated.

scholarly journals Effective Thermal Conductivity of Open Cell Polyurethane Foam Based on the Fractal Theory

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Kan Ankang ◽  
Han Houde
Keyword(s):  
Thermal Conductivity ◽  
Fractal Dimension ◽  
Effective Thermal Conductivity ◽  
Polyurethane Foam ◽  
Solid Phase ◽  
Fractal Theory ◽  
Heat Radiation ◽  
Total Thermal Conductivity ◽  
Equivalent Thermal Conductivity ◽  
Open Cell

Based on the fractal theory, the geometric structure inside an open cell polyurethane foam, which is widely used as adiabatic material, is illustrated. A simplified cell fractal model is created. In the model, the method of calculating the equivalent thermal conductivity of the porous foam is described and the fractal dimension is calculated. The mathematical formulas for the fractal equivalent thermal conductivity combined with gas and solid phase, for heat radiation equivalent thermal conductivity and for the total thermal conductivity, are deduced. However, the total effective heat flux is the summation of the heat conduction by the solid phase and the gas in pores, the radiation, and the convection between gas and solid phase. Fractal mathematical equation of effective thermal conductivity is derived with fractal dimension and vacancy porosity in the cell body. The calculated results have good agreement with the experimental data, and the difference is less than 5%. The main influencing factors are summarized. The research work is useful for the enhancement of adiabatic performance of foam materials and development of new materials.

scholarly journals Modified/Unmodified Nanoparticle Adsorbents of Cellulose Origin With High Adsorptive Potential for Removal of Pb(II) From Aqueous Solution

2017 ◽  
Vol 13 (27) ◽  
pp. 425
Author(s):  
Azeh Yakubu ◽  
Gabriel Ademola Olatunji ◽  
Folahan Amoo Adekola
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Adsorption Process ◽  
Correlation Coefficients ◽  
Solution Temperature ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Kinetics Of Adsorption ◽  
Kinetics Of

This investigation was conducted to evaluate the adsorption capacity of nanoparticles of cellulose origin. Nanoparticles were synthesized by acid hydrolysis of microcrystalline cellulose/cellulose acetate using 64% H3PO4 and characterized using FTIR, XRD, TGA-DTGA, BET and SEM analysis. Adsorption kinetics of Pb (II) ions in aqueous solution was investigated and the effect of initial concentration, pH, time, adsorbent dosage and solution temperature. The results showed that adsorption increased with increasing concentration with removal efficiencies of 60% and 92.99% for Azeh2 and Azeh10 respectively for initial lead concentration of 3 mg/g. The effects of contact time showed that adsorption maximum was attained within 24h of contact time. The maximum adsorption capacity and removal efficiency were achieved at pH6. Small dose of adsorbent had better performance. The kinetics of adsorption was best described by the pseudo-second-Order model while the adsorption mechanism was chemisorption and pore diffusion based on intra-particle diffusion model. The isotherm model was Freundlich. Though, all tested isotherm models relatively showed good correlation coefficients ranging from 0.969-1.000. The adsorption process was exothermic for Azeh-TDI, with a negative value of -12.812 X 103 KJ/mol. This indicates that the adsorption process for Pb by Azeh-TDI was spontaneous. Adsorption by Azeh2 was endothermic in nature.

Measurement and Prediction of Thermal Conductivity of Open Cell Rigid Polyurethane Foam

2001 ◽  
Vol 37 (4) ◽  
pp. 310-332 ◽  
Author(s):  
Wei-Han Tao ◽  
Hung-Che Hsu ◽  
Chih-Chen Chang ◽  
Chuan-Liang Hsu ◽  
Yung-Sen Lin
Keyword(s):  
Thermal Conductivity ◽  
Polyurethane Foam ◽  
Rigid Polyurethane Foam ◽  
Open Cell

Preparation of open cell rigid polyurethane foams and modified with organo-kaolin

2019 ◽  
Vol 56 (4) ◽  
pp. 435-447
Author(s):  
Guojian Wang ◽  
Tao Yang
Keyword(s):  
Compressive Strength ◽  
Polyurethane Foam ◽  
Coupling Agent ◽  
Silane Coupling Agent ◽  
Polyurethane Foams ◽  
Compressive Property ◽  
Rigid Polyurethane Foam ◽  
Open Cell ◽  
Silane Coupling ◽  
Cell Opening

The open cell rigid polyurethane foam (ORPUF) was prepared by adding chemical cell openers including O-500 and AK-9903. The FTIR results of cell openers and open cell rate of ORPUFs showed that O-500 has more effective cell opening capacity. In the ORPUF foaming formulation using O-500 as cell opener, silane coupling agent (KH-550) modified kaolin (organo-kaolin) was introduced into ORPUF with different weight loadings. The cellular morphology, apparent density, and compressive strength of the foams were tested in order to investigate the effects of organo-kaolin on the open cell rate and compressive property of the foams. The results showed that the open cell rate of ORPUFs slightly increased from 83.9% to 92.9% with the content of organo-kaolin. Meanwhile, compared to neat ORPUF, the compressive strength of foams increased by 72.8% when the content of introduced organo-kaolin was 4 parts per hundred of polyol by mass (php).

Modeling batch kinetics of cesium, cobalt and strontium ions adsorption from aqueous solutions using hydrous titanium oxide

2007 ◽  
Vol 95 (7) ◽  
Author(s):  
E. Metwally ◽  
R. O. Abdel Rahman ◽  
R. R. Ayoub
Keyword(s):  
Free Energy ◽  
Aqueous Solutions ◽  
Thermodynamic Parameters ◽  
Titanium Oxide ◽  
Contact Time ◽  
Cobalt Ions ◽  
Batch Kinetics ◽  
Batch Technique ◽  
Strontium Ions ◽  
Kinetics Of

Hydrous titanium oxide was chemically synthesized and tested as adsorbent material for the removal of cesium, cobalt and strontium ions from chloride waste solutions using batch technique. The influences of pH, contact time, and temperature have been reported. The uptake of both strontium and cobalt ions was found to be greater than that of cesium and the apparent sorption capacity of each ion increases with increase in temperature. Thermodynamic parameters such as changes in Gibbs free energy (Δ

Adsorption of methylene blue using modified adsorbents from drinking water treatment sludge

2016 ◽  
Vol 74 (8) ◽  
pp. 1885-1898 ◽  
Author(s):  
M. Nageeb Rashed ◽  
M. A. El-Daim El Taher ◽  
Somaya M. M. Fadlalla
Keyword(s):  
Methylene Blue ◽  
Drinking Water ◽  
Water Treatment ◽  
Contact Time ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Solution Temperature ◽  
Isotherm Models ◽  
Physical Activation ◽  
Adsorbent Dosage

This study aims to explore the preparation and application of alum sludge (AS) and mud sludge (MS) from a drinking water treatment plant to remove methylene blue (MB) dye from aqueous solution. The sludge (MS and AS) was treated by chemical and physical activation to obtain new adsorbents. The adsorption experiments were carried out under different conditions of initial dye concentration (50–100 mg/L) adsorbent dosage (0.05–0.25 g), solution pH (3–9), temperature (20–60 °C) and contact time (20–90 min). Scanning electron microscopy (SEM) and X-ray diffraction instruments were used for characterization of the developed adsorbents. The results show that sludge activated by nitric acid (0.25 M HNO3) and pyrolysis at 700 °C were the best chemically and physically activated adsorbents. The optimum adsorption conditions for the adsorption of MB are 100 ppm initial dye concentration, 1 hour contact time, 250 °C solution temperature, pH 7 and 0.25 g adsorbent dosage. Application of the Langmuir and Freundlich Isotherm models showed that adsorbents fitted the Langmuir model well. SEM studies indicated the porous structural aspects of sludge suitable for removing MB dye.

scholarly journals Carbon nano-ink coated open cell polyurethane foam with micro-architectured multilayer skeleton for damping applications

RSC Advances ◽  
2016 ◽  
Vol 6 (83) ◽  
pp. 80334-80341 ◽  
Author(s):  
Xiao-Chong Zhang ◽  
Fabrizio Scarpa ◽  
Ronan McHale ◽  
Andrew P. Limmack ◽  
Hua-Xin Peng
Keyword(s):  
Carbon Nanotube ◽  
Energy Dissipation ◽  
Polyurethane Foam ◽  
Open Cell ◽  
Frictional Damping ◽  
Open Cell Foams ◽  
Carbon Nanotube Ink

Carbon nanotube ink coated multilayered polyurethane open cell foams utilize the CNT–CNT interfacial frictional damping mechanism, thus dramatically improving the foam energy dissipation capability by 270%.

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