Composite silicone-SAPO-34 foams: experimental characterization for open cycle applications

In this work, novel composite silicone-SAPO-34 foams have been prepared and experimentally characterized for application in desiccant open cycles. Water adsorption isotherms of several samples have been measured by a gravimetric dynamic vapour sorption analyser at 30°C and 70°C up to the relative humidity RH= 75%, representing typical process and regeneration air conditions in desiccant evaporative cooling cycles. Adsorbent foams manufactured with 20%, 40% and 60% weight fraction of SAPO-34 have been compared with the pure SAPO-34 powder. Results highlighted that the prepared foams adsorb a significant amount of water, according to the initial mass fraction of zeolite used in the compound. Moreover, the tested foams exhibited sufficiently fast water sorption rate for practical application in a desiccant open cycle system.

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Thermodynamic theory of solutions

Thermodynamics and Kinetics in Materials Science ◽

10.1093/oso/9780198528036.003.0005 ◽

2005 ◽

Author(s):

Boris S. Bokstein ◽

Mikhail I. Mendelev ◽

David J. Srolovitz

Keyword(s):

Mass Fraction ◽

Total Mass ◽

Molar Fraction ◽

Weight Fraction ◽

Weight Percent ◽

Thermodynamic Theory ◽

Point Of View ◽

Condensed Phases ◽

Ideal Gases ◽

Definition Of

A solution is a homogeneous mixture consisting of two or more components in which the composition can be continuously varied (within some range) with no change of phase. Solutions can be gases, liquids, or solids. We have already considered the properties of gaseous solutions (when we considered a mixture of ideal gases). In this chapter, we focus on condensed phases (i.e. liquids and solids). The composition of a solution can be described in several ways. Here are the most common: 1. The molar fraction of the ith component, xi, is the ratio of the number of moles of component i, ni, to the total number of moles of all species within the solution, n: 2. The weight fraction of the ith component, [i], is the ratio of the mass of component i, wi, to the total mass of all species within the solution, w: the weight fraction is often written as a weight percent [wt%] = 100[i]. 3. The molarity of the ith component, ci, is the number of moles of component i, ni per liter of solution, V: 4. The molality of ith component (used only for dilute solutions), mi, is the number of moles of component i, in 1 kg of solvent. There are several other definitions used to describe the composition of a solution, but we shall only refer to those described above in this text. The reason that there are so many definitions of the composition is related to how the term ‘‘concentration’’ is applied. For example, from the physical–chemical point of view, the molar fraction is the most convenient definition of the concentration since it is on an atomic basis. However, from the point of view of someone who has to prepare solutions from separate solutes and solvents, the mass fraction is the most convenient definition since it is directly related to the mass of the components, rather than the number of moles of the component. The former is easily measured, while the latter requires the additional knowledge of the molecular weight (and a trivial calculation).

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Analysis of Water Adsorption on Chitosan and Its Blends with Hydroxypropylcellulose

e-Polymers ◽

10.1515/epoly.2007.7.1.181 ◽

2007 ◽

Vol 7 (1) ◽

Cited By ~ 9

Author(s):

Maria Mucha ◽

Kazimierz Wańkowicz ◽

Jacek Balcerzak

Keyword(s):

Hydrogen Bonds ◽

Thermodynamic Parameter ◽

Solid Surface ◽

Mass Fraction ◽

Water Adsorption ◽

Vapour Phase ◽

Heat Of Adsorption ◽

Water Molecules ◽

Monomolecular Layer ◽

Adsorption Of Water

AbstractChitosan (CH) and hydroxypropylcellulose (HPC) adsorb water easily by hydrogen bonds formed with hydroxyl and amide groups present in their structures. Heat of adsorption is a thermodynamic parameter which is used to estimate the type of adsorbate molecule bond on a solid surface, among the others. Adsorption of water from vapour phase on chitosan, hydroxypropylcellulose and blends of both biopolymers in the form of films were carried out. Isotherms of water adsorption in the samples were described by the GAB equation. Correlations between mass fraction of chitosan in the sample (wf) and the values of GAB coefficients were obtained. From parameter c in the GAB equation mean heat of adsorption of the first monomolecular layer of water molecules E1, and pure molar heat of adsorption q were determined.

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Improved Plastic-Al Pipe Based System for Refrigeration of Energy Existed in Urban Sewage

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.2436 ◽

2013 ◽

Vol 275-277 ◽

pp. 2436-2440

Author(s):

Jin Gang Yang ◽

Jia Fu Xiao

Keyword(s):

Heat Exchange ◽

Energy Recovery ◽

Water Source ◽

Coefficient Of Performance ◽

Environment Protection ◽

Practical Utilization ◽

Urban Sewage ◽

Cycle System ◽

Average Coefficient ◽

Open Cycle

In order to recover the urban sewage energy ,a lab-scale equipment for the sewage energy recovery based on water source heat pump was developed and researched experimentally .The technique of indirect heat exchange by the plastic-Al pipe to recover the urban sewage energy, i.e., the corrosion of the heat exchanger, laying the foundation for the practical utilization of sewage energy. The experimental results show that the developed system is favorable to the environment protection and energy conservation, satisfying the cooling duty requirement with the average coefficient of performance 4.15 in the open cycle system and the average coefficient of performance 3.64 in the close cycle system.

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Calculation and Optimization of Plasma Utilization Process of Inflammable Wastes after Spent Nuclear Fuel Recycling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1040.433 ◽

2014 ◽

Vol 1040 ◽

pp. 433-436 ◽

Cited By ~ 5

Author(s):

A.G. Karengin ◽

A.A. Karengin ◽

I.Yu. Novoselov ◽

N.V. Tundeshev

Keyword(s):

Nitric Acid ◽

Acid Solution ◽

Nuclear Fuel ◽

Nitric Acid Solution ◽

Mass Fraction ◽

Spent Nuclear Fuel ◽

Air Plasma ◽

Practical Application

There are shown modeling results of the joint utilization process of tributylphosphate’s spent solutions into hexachlorinebutadiene for uranium and plutonium extraction from nitric acid solution of spent nuclear fuel and its recycling wastes. Utilization process was carried out for widely temperature and mass fraction ranges of air plasma coolant. Also optimal consist of inflammable water-organic compositions and modes for practical application this process in air plasma was determined.

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Thermodynamic investigation of dual-separator Kalina cycle system: Comparative study

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/0957650917720288 ◽

2017 ◽

Vol 232 (3) ◽

pp. 282-292

Author(s):

Rasool Bahrampoury ◽

Ali Behbahaninia

Keyword(s):

Sensitivity Analysis ◽

Weak Solution ◽

Heat Exchangers ◽

Mass Fraction ◽

Power Production ◽

Base Case ◽

Thermodynamic Investigation ◽

Kalina Cycle ◽

Cycle System ◽

Mass Fractions

In this study, an arrangement of Kalina cycle is proposed in which it is intended to implement weak solution of Kalina cycle system 11 (KCS 11) for more power production. In this cycle, which is a version of KCS11 (KCS111), the weak solution of the traditional separator is heated in hot section of the evaporator. The stream that now includes vapor is separated in high-temperature separator that brings about an extra potential to produce work. In order to set pinch temperature in each of the heat exchangers included in the cycles an iterative method is used. The two cycles are compared for the same conditions as the base case, which is followed by a comprehensive sensitivity analysis. The consequences of streams’ curves in the heat exchangers are considered to present analytical justification for the improvements. Comparing the cycles at the base condition, it is observed that the presented cycle improves the exergy efficiency by nearly 18% while more than 17% improvement at the optimum ammonia mass fraction is achievable. Results show that, the proposed cycle produces larger mass flow rate of vapor passing through the turbines and is more efficient than KCS 11 for varying ammonia mass fractions. Results indicate that the trend of thermal efficiency versus ammonia mass fraction is descending for the both cycles.

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A Modified Scheffe's Simplex Lattice Design Method in Development of Ceramic Carriers for Catalytic Neutralizers of Gas Emissions

Chemistry Journal of Moldova ◽

10.19261/cjm.2021.779 ◽

2021 ◽

Author(s):

Valery Ved ◽

Hanna Ponomarenko ◽

Yevhenia Ponomarenko ◽

Konstantin Gorbunov

Keyword(s):

Mass Fraction ◽

Design Method ◽

Weight Fraction ◽

Ceramic Materials ◽

Gas Emissions ◽

Catalyst Carrier ◽

Lattice Design ◽

Simplex Lattice Design ◽

Simplex Lattice ◽

Purification Equipment

A modified Scheffe's simplex lattice design method is proposed to study the properties of multicomponent materials. This modified Scheffe's method allowed determining the optimal compositions of cordierite and corundum based ceramic materials that are used as catalyst carrier for gas purification equipment. The obtained material (0.63-1.25 mm weight fraction of cordierite of 0.35 mass% fraction; < 0.63 mm weight fraction of cordierite of 0.35 mass% fraction; < 0.06 mm weight fraction of corundum of 0.2 mass% fraction; 1.25-2.5 mm weight fraction of cordierite of 0.2 mass% fraction) was used successfully for the manufacturing of catalytic neutralizers of gas emissions.

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Effect of Low Ammonia Mass Fraction of the Base Solution on Theoretical Cycle Efficiency of Kalina Cycle System (kcs-34)

Journal of Mechanical Engineering ◽

10.3901/jme.2012.24.152 ◽

2012 ◽

Vol 48 (24) ◽

pp. 152 ◽

Cited By ~ 2

Author(s):

Huiqin REN

Keyword(s):

Mass Fraction ◽

Kalina Cycle ◽

Cycle System ◽

Base Solution ◽

Cycle Efficiency

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Hysteresis and thermodynamic properties of water sorption in ‘Malagueta’ pepper seeds

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v22n9p658-663 ◽

2018 ◽

Vol 22 (9) ◽

pp. 658-663

Author(s):

Hellismar W. da Silva ◽

Renato S. Rodovalho ◽

Isneider L. Silva

Keyword(s):

Free Energy ◽

Thermodynamic Properties ◽

Gibbs Free Energy ◽

Water Sorption ◽

Water Adsorption ◽

Gravimetric Method ◽

Free Energy Of Adsorption ◽

Adsorption And Desorption ◽

Moisture Contents ◽

Compensation Theory

ABSTRACT The objective of this study was to determine hysteresis, enthalpy, entropy, enthalpy-entropy compensation theory and Gibbs free energy for water adsorption and desorption in ‘Malagueta’ pepper seeds. Hygroscopic equilibrium moisture contents were determined by the static gravimetric method, with water activity in the range from 0.29 to 0.90 and temperatures of 30, 40 and 50 °C. The hysteresis of the ‘Malagueta’ pepper seeds reduces with the increase of temperature. Enthalpy, entropy and Gibbs free energy of adsorption and desorption increase with the reduction of the moisture content of the seeds. The enthalpy-entropy compensation theory is valid for the sorption processes. The sorption of water between seeds and the surrounding air is a non-spontaneous process.

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