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Energy Storage and Saving 2022年第4期1卷 259-271页

作者： Atef Chibani Slimane Merouani Aissa Dehane Cherif Bougriou Laboratory of Environmental Process Engineering Department of Chemical EngineeringUniversity Salah Boubanider Constantine 3ConstantineP.O.Box 72Algeria Department of Mechanical Engineering University of Mostefa Ben BoulaidBatna 2Batna05000Algeria Department of Process Engineering Faculty of Sciences and Applied SciencesLarbi Ben M’hidi University04000Oum El BouaghiAlgeria

An advanced ANSYS FLUENT-based model was developed for hydrogen recovery from a multi-tubular fixed-bed metal hydride(MH)reactor of large-scale design.The model was firstly validated by comparing its results to specific experimental data.Mass and heat transfer processes inside the fixed bed were investigated for various pressures and thermochemical characteristics of the MH(thermal conductivity,porosity and reaction parameters).The findings were reported as average,local and spatial changes in the metal’s bed temperature and hydrogen content.During the initial stage of the endothermic desorption(tdesorption rate constant and activation energy,significantly impacted the resulting mass and heat fluxes inside the bed material.

关键词： Hydrogen storage Metal hydride(MH) desorption Heat and mass transfer Mathematical model

Isothermal Adsorption and desorption Properties of Marine Shales on Longmaxi Shale in South China

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Open Journal of Geology 2017年第12期7卷 1819-1835页

作者： Taoyue Chang Yuanli Shu Yue Ma Xinyi Xu Yue Niu College of Science China University of Petroleum Beijing China

The investigation of adsorption and desorption properties of shale are important for estimating reserves and exploitation. The shale samples used in this paper were from the marine shale on Longmaxi shale in Sichuan and Hubei province, China. A series of analyses, such as organic carbon content test, vitrinite reflectance test, rock pyrolysis, X-ray diffraction, and N2/CO2 adsorption were performed. Gravimetric method with magnetic suspension balance was used to conduct isothermal adsorption and desorption experiments. The Langmuir, Freundlich, Langmuir-Freundlich, D-R, semi-pore, and Tothequations were used to fit the isothermal adsorption and desorption curves. And adsorption potential theory was used to explain the adsorption and desorption process. According to the results, the shale samples have a high level of organic carbon content with the same organic matter type II1 and high degree of maturation. The volume of adsorption increases rapidly and slows down to stable with the pressure increasing. desorption is the inverse process of adsorption and 10 MPa - 0.5 MPa is the main period of shale gas desorption. The fitting results show that three-parameter isotherm equations are better than the two-parameter ones. The adsorption temperature has a great influence on adsorption volume, little effect on potential energy. Adsorption potential varies under different TOC to affect adsorption properties. Moreover, a large adsorption potential means that the gas molecule is easy to adsorb but difficult to desorb.

关键词： Shale Gas Isothermal Adsorption and desorption Gravimetric Method Adsorption Potential

Phosphate desorption Characteristics of Some Representative Soils of Bangladesh: Effect of Exchangeable Anions, Water Molecules and Solution to Soil Ratios

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Open Journal of Soil Science 2012年第3期2卷 234-241页

作者： Mohammad Z. Afsar Sirajul Hoque K. T. Osman Department of Soil Science Faculty of Biological Sciences University of Chittagong Chittagong Bangladesh Department of Soil Water and Environment Faculty of Biological Sciences University of Dhaka Dhaka Bangladesh

Establishment of phosphate (P) retention and release capacity of soils is essential for effective nutrient management and environmental protection. In this experiment, we studied the influence of soil properties on P desorption and the relationship between phosphate sorption and desorption. Among the soil series, the Ghior soil had the highest percent clay (59.32%) and free iron oxide (15241 mg·kg–1) content. Along the catena of the calcareous soils, percent clay contents increased. For sorption study, the soils were equilibrated with 0.01 M CaCl2 solution containing 0, 1, 2, 4, 8, 16, 25, 50, 100 and 150 mg·P·L–1 solution. For desorption, three extractants namely, SO42- (0.005 M) as Na2SO4, HCO3- (0.01 M) as NaHCO3 and distilled water were used at extractant to soil ratios of 30:1, 60:1 and 100:1 (v/w). Among the sorption equations, the Langmuir equation showed better fit to the sorption data at higher P concentrations. The amount of phosphate desorbed by all the three extractants increased significantly with the increasing extractant to soil ratios. Phosphate desorption by and water molecules was highly correlated with pH, percent clay and free iron oxide content of the soil. Significant positive correlation (r > 0.64, P L). Phosphate desorption by SO42- and water molecules was also positively correlated with Freundlich constant, N (r > 0.67, P 0 (r > 0.72, P –0.77, P L). The results suggest that freshly sorbed phosphate ions (inner-sphere complex forming species) can be readily desobed by outer-sphere complex forming species like sulphate and bicarbonate ions. Water molecules also desorbed significant amount of freshly sorbed phosphate from the soil colloids.

关键词： Phosphate Sorption Extractant to Soil Ratio Surface Complexation of Anions Labile Forms of P Phosphate desorption

A New Approach for Atrazine desorption, Extraction and Detection from a Clay-Silty Soil Sample

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American Journal of Analytical Chemistry 2011年第8期2卷 63-68页

作者： Rossy Feria-Reyes Paola Medina-Armenta M. Teutli-León M. G. García-Jiménez I. González 不详

This paper reports an alternative method for extraction, detection and quantification of atrazine from a clay-silty soil. Atrazine adsorption isotherm for this kind of soil fits to a Freundlich adsorption isotherm with a correlation coefficient of 0.994, sorption intensity 1/n = 0.718 and Kf = 1, with a maximum soil adsorbed atrazine concentration of 8 mg g–1. Atrazine desorption was approached using several surfactants including non-ionic (Triton X-100, Triton X-114, and Triton X-405), anionic (SDS) and cationic (CTAB), these surfactants were used at critical micellar concentration (CMC) and higher concentrations. Atrazine quantification was done by high resolution liquid chromatography coupled to spectrophotometric detection (HPLC-UV), optimized conditions correspond to a flow rate of 1.0 mL min–1, λ = 260 nm, a C18 PAH Agilent-Eclipse column with a mobile phase of CH3OH/1 × 10–3, a phosphate buffer, pH 3.2/CH3CN 55:30:15 (v/v). At these conditions it can be obtained a good chromatographic separation of atrazine and soil organic matter. Atrazine desorption was aided by surfactants at CMC conditions, it can be claimed that atrazine desorption was enhanced by surfactants since desorption, from higher to lower, goes as follows: 98.5% with Triton X-114, 98% with SDS, 89.5% with Triton X-405, 86.5% with Triton X-100;and 45% with CTAB.

关键词： Atrazine desorption Soil Surfactants

Thermodynamic Characteristics of Adsorption-desorption of Methane in 3#Coal Seam of Sihe

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Natural Resources 2014年第12期5卷 782-794页

作者： Dongmin Ma Jianchang Zhang Jianping Bai Hui Zhang Xi’an University of Science and Technology Xi’an China National Key Laboratory of Coal and CBM Co-Mining Technology Jincheng China

A series of methane adsorption-desorption isotherm experiments on anthracite of No. 3 Sihe coal mine were conducted at 20°C, 25°C, 30°C, 35°C and 40°C respectively. Based on Clausius-Clapeyron equation, isosteric heat of adsorption and maximum heat of adsorption has been calculated. These calculations indicate that the maximum heat of adsorption in process of elevated pressure (adsorption) and lowered stress (desorption) is 23.31 KJ/mol and 24.02 KJ/mol, so it belongs to physical adsorption. However, the latter is higher than the former. From the point of view of thermodynamics, in the adsorption-desorption equilibrium system, dropping pressure alone does not lead to desorption, but it improves adsorption of water vapor molecules on the surface of the coal pores. The adsorption heat of water vapor molecules is greater than 40 KJ/mol, so the methane on the surface of coal pores will be easily replaced by water vapor, and the desorption of methane occurs eventually. Thus, the gas production in coalbed methane well by pressure reduction is consistent with the negative pressure for gas extraction.

关键词： Methane Adsorption desorption Thermodynamics

A STUDY ON THE KINETICS OF CO/Re(0001)desorption UNDER A GAS AMBIENCE(Ⅱ)——desorption UNDER A GAS AMBIENCE OF CO ISOTOPE MIXTURE

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Progress in Natural Science:Materials International 1991年第4期 367-375页

作者：郭燮贤向宁宋真张林虎刘宪春翟润生王德峥 Academia Sinica Dalian 116023 PRC State Key Laboratory for Catalysis Dalian Institute of Chemical Physics

The isotope switch and temperature programed desorption techniques are used to study thedesorption kinetics of CO16/Re(0001)in a gas ambience of mixed isotopes(CO16+CO18).Thedesorption kinetics of CO16under this condition is again not of a first order.The experimental resultsare satisfactorily explained by the concerted adsorption/desorption mechanism.In accordance with thismechanism,it is emphasized that due to the specific feature of screen effect between the coadsorbedisotopic species,the isotope distribution on the surface is nonuniform,which causes a nonlinear featureof the desorption rate of AAD process.However,the first-order kinetics is applicable for the initial rate att=0 because the screen effect is nil at this moment.

关键词： desorption exchange kinetics

Experimental Studies on the Influence of HCO3- on Absorption and desorption of CO2from Ammonia Solution

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Advances in Materials Physics and Chemistry 2012年第4期2卷 240-243页

作者： Shaojian Jiang Wei Zhong Rui Peng Yong Jiang Jun Zhang chool of Energy Science and Engineering Central South University Changsha China School of Energy Science and Engineering Central South University Changsha China

With aqueous ammonia in the process of CO2 absorption and desorption to join sodium bicarbonate, the influence of HCO3- on CO2 absorption and desorption from ammonia solution was investigated through the experimental analysis of the desorption quantity of CO2, desorption rate, CO2 loading and the absorption rate. The experimental results showed that, in experimental conditions, The desorption rate decreased gradually with increasing ammonia concentrations. The desorption rate increased 12%, 17%, 19% and 28.8% when 1 mol/L of ammonia solution is added in 0.1 mol/L, 0.3 mol/L, 0.5 mol/L and 1 mol/L of sodium bicarbonate. The higher concentration of ammonium bicarbonate solution which was added sodium bicarbonate,the more observably the effect of CO2 desorption was promoted. The absorption rate had dropped when absorption process added 0.3 mol/L sodium bicarbonate, the CO2 loading was a little change.

关键词： Ammonia desorption the desorption Rate CO2 Absorption CO2 Loading

Adsorption and desorption phenomena on thermally annealed multi-walled carbon nanotubes by XANES study

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Chinese Physics B 2019年第9期28卷 145-149页

作者： Camile Rodolphe Tchenguem Kamto Bridinette Thiodjio Sendja Jeannot Mane Mane University of Yaounde Ⅰ Faculty of ScienceDepartment of PhysicsYaoundeCameroon University of Yaounde Ⅰ National Advanced School of EngineeringDepartment of Mathematic and Physical ScienceYaoundeCameroon University of Dschang DschangCameroon

The multi-walled carbon nanotubes(MWCNTs) studied in this work were synthesized by the catalytic chemical vapor deposition(CCVD) process, and were thermally annealed by the hot filament plasma enhanced(HF PE) method at 550℃ for two hours.The x-ray absorption near edge structure(XANES) technique was used to investigate the adsorption and desorption phenomena of the MWCNTs at normal and grazing incidence angles.The adsorbates were found to have different sensitivities to the thermal annealing.The geometry of the incident beam consistently gave information about the adsorption and desorption phenomena.In addition, the adsorption of non-intrinsic potassium quantitatively affected the intrinsic adsorbates and contributed to increase the conductivity of the MWCNTs.The desorption of potassium was almost 70% greater after the thermal annealing.The potassium non-intrinsic adsorbates are from a physisorption mechanism whereas the intrinsic adsorbates result from chemisorption.

关键词： multi-walled carbon nanotubes thermal annealing adsorption desorption

THERMAL desorption STUDY OF DEUTERIUM ON Si (100) SURFACE

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Chinese Physics Letters 1985年第4期2卷 149-152页

作者： HU Ji-huang CHEN Ke-ming HU Xin-gen ZHUANG Cheng-qun WANG Xun Modern Physics Institute Fudan UniversityShanghai

The thermal desorption spectra study of deuterium on Si(100)surface shows that two adsorption states the monodeuteride phase and the dideuteride phase can be formed.The activation energies of desorption for these two ... 详细信息

关键词： adsorption desorption SURFACE

ADSORPTION AFFINITY AND desorption POTENTIAL OF CADMIUM IN SOILS OR COLLOIDS AND THEIR APPLICATIONS

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Chinese Science Bulletin 1987年第16期32卷 1136-1140页

作者：陈怀满 Institute of Soil Science Academia Sinica Nanjing

Cadmium (Cd) is a dangerous environmental pollutant and its major hazard to man is its presence in foodstuffs through contamination in excessive amount coming from polluted soil and water. The uptake of cadmium by plants is influenced by cadmium activity in soil solution, which in turn is controlled mainly by adsorption and desorption of Cd in soils or soil colloids.The adsorption-desorption process depends upon many factors, such

关键词： desorption pollutant cadmium polluted contamination uptake dangerous Adsorption adsorbed colloid