Fine quantitative characterization of high-H2S gas reservoirs under the influence of liquid sulfur deposition and adsorption

In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs,three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-pressure core displacement experiments.Fine quantitative characterization of the cores in three steady states(original,after sulfur injection,and after gas flooding)was carried out using the nuclear magnetic resonance(NMR)transverse relaxation time spectrum and imaging,X-ray computer tomography(CT)of full-diameter cores,basic physical property testing,and field emission scanning electron microscopy imaging.The loss of pore volume caused by sulfur deposition and adsorption mainly comes from the medium and large pores with sizes bigger than 1000μm.Liquid sulfur has a stronger adsorption and deposition ability in smaller pore spaces,and causes greater damage to reservoirs with poor original pore structures.The pore structure of the three types of carbonate reservoirs shows multiple fractal characteristics.The worse the pore structure,the greater the change of internal pore distribution caused by liquid sulfur deposition and adsorption,and the stronger the heterogeneity.Liquid sulfur deposition and adsorption change the pore size distribution,pore connectivity,and heterogeneity of the rock,which further changes the physical properties of the reservoir.After sulfur injection and gas flooding,the permeability of TypeⅠreservoirs with good physical properties decreased by 16%,and that of TypesⅡandⅢreservoirs with poor physical properties decreased by 90%or more,suggesting an extremely high damage.This indicates that the worse the initial physical properties,the greater the damage of liquid sulfur deposition and adsorption.Liquid sulfur is adsorbed and deposited in different types of pore space in the forms of flocculence,cobweb,or retinitis,causing different changes in the pore structure and physical property of the reservoir.

Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells

Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet challenging.Herein,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel cells.The modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/C.Operando in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct pathway.Density functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance H_(2)O dissociation to improve electrocatalytic performance.This synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources.

AN APPROACH TO CALCULATE THE SURFACE TENSION OF THE LIQUID NITROGEN FILM ON SOLIDS FROM AN ADSORPTION ISOTHERM

The equations, used in this paper to calculate the surface tension of the liquid nitrogen film formed by the physical adsorption on many different model solids (e.g. spherical partiele, plane particle and spherical cavity pores or cylindrical pores at the openings of both ends in solid bodies), have been derived on the thermodynamie principle. The calculated results have shown that the surface tension (γ) of the adsorbed liquid nitrogen film on most of non-porous solid surfaces diminishes with the rise of the nitrogen gas pressure (p) or of the adsorbed layers (n) at 77.3K; when p reaches the vapour pressure (p_s) of the bulk liquid nitrogen, y turns into the surface tension (γ_o) of the bulk liquid nitrogen; whgn p /p, 【0.98, there is an obvious difference between γ and γ_O.

THE STUDY OF INTERACTION OF SOLID-LIQUID ADSORPTION SYSTEM BY USING THE FLOW INJECTION-SPECTROPHOTOMETRY SYSTEM

The flow injection analysis was firstly used for studying a solid-liquid adsorption system, and the dynamics process in the adsorption of dyestuff with regenerable chitin was traced by an online method of flow injection-spectrophotometry. Experimental results indicate that there is a linearization between the tested signals and the height of peaks with reciprocity coefficient 0.9999 by using the flow injection-spectrophotometry system to study the dynamics adsorption process in solidliquid system. The method shows a good stability and reproducibility. It provides a new method for the studies on adsorption dynamics in solid- liquid system.

Apparent Active Adsorption Force at a Solid-Liquid Interface with Active Adsorption

The paper presents a new relationship between the three surface tensions on the solid-liquid-vapor interface, γ_(sl)-γ_(sv)+γ_(lv)cosθ=βin order to understand the wetting on the liquid-solid interface in the case of active adsorption.The authors suggest a new force“apparent active adsorption force”βto take part in the balance at the three interface lines of contact in the solid-liquid-vapor phases,its dimen- sion isβ=Σα_iRT(Γ_i^(sl)-Γ_i^(sv)+Γ_i^(lv)cosθ),and its direction is dependent on the sign of β,whenβis a positive, the direction is agree with surface tension of the sol- id-vapor interface γ and vice versa.

Synthesis of polymeric ionic liquids material and application in CO2 adsorption

We synthesized one quaternary ammonium polymeric ionic liquids（PILs）P[VBTHEA]Cl and three imidazolium PILs of P[VEIm]Br, P[VEIm]BF, P[VEIm]PFby free-radical polymerization in solution. These PILs were characterized by FT-IR,H-NMR,C-NMR, TGA, XRD and SEM. Their COadsorption capacities were measured under different pressures and temperatures by constant-volume technique. It was observed that quaternary ammonium PILs of P[VBTHEA]Cl have higher adsorption capacity for COthan those imidazolium PILs, following P[VBTHEA]Cl > P[VEIm]PF> P[VEIm]BF> P[VEIm]Br, which may be ascribed to higher positive charge density on ammonium cation than that on imidazolium cation and thus stronger interaction with CO, consistent with the results from dual-mode adsorption model that ammonium PILs have much higher CObulk absorption than imidazolium PILs. COadsorption capacity of P[VBTHEA]Cl is 9.02 mg/g under 295 K and 1 bar, which is comparable to that of some other PILs, and is much higher than that of the corresponding ILs monomer. These PILs have good adsorption selectivity for COover Nand regeneration efficiency.

Ionic Liquid Modified Inorganic Nanoparticles for Gaseous Phenol Adsorption

Ionic liquid modified silica nanoparticles were synthesized using a simple silane chemistry,followed by substitution reaction. The phenol adsorption performance was tested using temperature programmed desorption technique. The experimental results reveal that the introduction of ionic liquids on the surface of silica nanoparticles can improve the adsorption capacity of phenol compared to the pure silica nanoparticles.The initial adsorption capacity reaches 0.312 mmol·g^-1 at 25 ℃ under total pressure of 0.2 bar and it decreases slightly in the following adsorption-desorption cycles. The results demonstrate that introduction of ionic liquids can improve the phenol adsorption capacity and the simple material preparation process is feasible for industrial applications.

Formation of AgI/Ag_3PO_4 solid solution on alumina for enhancing radioactive iodine adsorption at high temperatures

Radioiodine-131 is one of the pernicious radionuclides released during nuclear accidents, as its radioactivity can potentially affect public health and safety.To prevent radioiodine-131 from being released into the environment, the use of adsorbents that are highly efficient at high temperatures is significantly important. The radioactive gas from the nuclear core in an accident, such as the Fukushima nuclear accident, is usually released occurs under high-temperature conditions. Therefore, in this study, a 10 wt% silver phosphate-loaded alumina(Ag_3 PO_4/Al_2 O_3) adsorbent was prepared. Further, its performance toward radioiodine adsorption was tested at high temperatures up to 750 0 C, using Al_2 O_3 and traditional 10 wt% Ag/Al_2 O_3 adsorbent as controls. The results of the iodine adsorption test indicated that the 10 wt% Ag_3 PO_4/Al_2 O_3 adsorbent showed a higher decontamination factor than did the 10 wt% Ag/Al_2 O_3 adsorbent by two orders of magnitude at 650 and 750℃. Results of the iodine desorption test revealed that the new adsorbent could be effectively used at 750 ℃. The characteristic powder X-ray diffraction, nitrogen adsorption-desorption isotherm,X-ray photoelectron spectroscopy, and thermogravimetric analysis-differential scanning calorimetry data indicated that the enhanced adsorption ability at high temperatures was attributed to the formation of a solid solution between silver iodide and Ag_3 PO_4.

Thermal rectification induced by Wenzel–Cassie wetting state transition on nano-structured solid–liquid interfaces

Thermal rectification refers to the phenomenon by which the magnitude of the heat flux in one direction is much larger than that in the opposite direction.In this study,we propose to implement the thermal rectification phenomenon in an asymmetric solid–liquid–solid sandwiched system with a nano-structured interface.By using the non-equilibrium molecular dynamics simulations,the thermal transport through the solid–liquid–solid system is examined,and the thermal rectification phenomenon can be observed.It is revealed that the thermal rectification effect can be attributed to the significant difference in the interfacial thermal resistance between Cassie and Wenzel states when reversing the temperature bias.In addition,effects of the liquid density,solid–liquid bonding strength and nanostructure size on the thermal rectification are examined.The findings may provide a new way for designs of certain thermal devices.

SOLID MATRICES FOR EXPANDED BED ADSORPTION OF PROTEINS

Expanded bed adsorption (EBA) has been introduced as a primary recovery step for protein purification from a whole fermentation broth or unclarified cell homogenates. It can also be integrated with a fermentation or cell disruption process. Solid matrix is the principal pillar supporting the successful application of the EBA technology. This article summarizes the solid matrices employed in and developed for the EBA process to date. Further development of solid matrices for the expanded bed technique in the recovery of various biological substances from different sources has been addressed.

Cellulose-based Polymeric Liquid Crystals as a Biomimetic Modifier for Suppressing Protein Adsorption

A novel biomimetic protein-resistant modifier based on cellulose-based polymeric liquid crystals was described（PLCs）. Two types of PLCs of propyl hydroxypropyl cellulose ester（PPC） and octyl hydroxypropyl cellulose ester（OPC） were prepared by esterification from hydroxypropyl cellulose, and then were mixed with polyvinyl chloride and polyurethane to obtain composite films by solution casting, respectively. The surface morphology of PLCs and their composite films were characterized by polarized optical microscopy（POM） and scanning electron microscopy（SEM）, suggesting the existence of microdomain separation with fingerprint texture in PLC composite films. Water contact angle measurement results indicated that hydrophilicity of PLC/polymer composite films was dependent on the type and content of PLC as well as the type of matrix due to their interaction. Using bovine serum albumin（BSA） as a model protein, protein adsorption results revealed that PLCs with protein-resistant property can obviously suppress protein adsorption on their composite films, probably due to their flexible LC state. Moreover, all PLCs and their composites exhibited non-toxicity by MTT assay, suggesting their safety for biomedical applications.

MCM-36 zeolites tailored with acidic ionic liquid to regulate adsorption properties of isobutane and 1-butene

Adsorption properties of an adsorbent or a catalyst towards adsorbates are crucial in the process of adsorption separation or catalytic reaction. Surface morphology and structure of adsorbents have a significant impact on the adsorption properties. In this study, a novel acidic ionic liquid, 1-butyl-3-(triethoxysilylpropyl)imidazolium hydrogen sulfate(i.e., [BTPIm][HSO_4]), was synthesized and subsequently grafted onto the MCM-36 zeolite for the regulation of its adsorption properties towards isobutane and 1-butene. The resultant [BTPIm][HSO_4]-immobilized MCM-36(i.e., MCM-36-IL) was characterized by FT-IR, XPS, XRD, SEM, TG/DTG and N_2 adsorption–desorption measurement. It was found that the specific surface area, micropore volume and mesopore volume of the MCM-36 support underwent a reduction upon the immobilization of ionic liquid,while the surface density of acid increased from 0.0014 to 0.0035 mmol·m^(-2). The adsorption capacity of isobutane and 1-butene on the MCM-36-IL was determined by a static volumetric method. Results demonstrated that the interaction between isobutane and MCM-36-IL was enhanced and the interaction between 1-butene and MCM-36-IL was reduced. As a result, a tunable adsorption ratio of isobutane/1-butene on MCM-36 was achieved.With the increase in surface density of acid and the tunable adsorption ratio of isobutane and 1-butene on the functionalized MCM-36, the acidic ionic liquid-immobilized zeolites are beneficial to obtain an improved reaction yield and a prolonged catalyst life in the reactions catalyzed by solid acid.

Regulation of isobutane/1-butene adsorption behaviors on the acidic ionic liquids-functionalized MCM-22 zeolite

The adsorption ratio of isobutane/1-butene on the catalyst surface is one of the most important factors for the C_4 alkylation process. Regulation of isobutane/1-butene adsorption ratio on the zeolite-supported acid catalyst is a big challenge for catalyst preparation. To regulate the isobutane/1-butene adsorption ratio, four types of ionic liquid(i.e., IL) with different alkyl chain lengths and different acid group numbers were synthesized and were subsequently immobilized onto the MCM-22 zeolite. The as-synthesized IL-immobilized MCM-22(i.e., MCM-22-IL)was characterized by FTIR, TGA, BET, XPS and XRD, and their adsorption capacities and adsorption molar ratios of isobutane to 1-butene(I/O) were investigated to correlate with surface features of MCM-22-IL. Results showed that the immobilization of ILs led to a decrease of specific surface area and pore volume. But the surface density of acid groups was increased and the adsorption molar ratio of isobutane/1-butene(I/O) was significantly improved by the immobilization of ionic liquids. The adsorption molar ratio of I/O is substantially improved from 0.75 to above 0.9 at 300 kPa upon immobilizing ILs. Although the alkyl chain length of ILs was found to have little effect on the adsorption molar ratio of I/O, the increase of acid group numbers led to a dramatic decrease in the adsorption I/O ratio. The results illustrated that immobilizing ionic liquids is an effective way to modify the textural, chemical and morphological properties of MCM-22. Accordingly, the immobilization of ionic liquids provides a novel and a feasible way to regulate the adsorption I/O ratio on an adsorbent or a solid catalyst.

INVESTIGATION OF THE SOLID- SOLID SURFACE ADSORPTION OF Eu_2O_3 ON AMORPHOUS Al_2O_3

Solid-solid surface adsorption of Eu2O3 on amorphous Al2O3 have been investigated by Mossbauer spectroscopy, X- ray diffraction analysis and laser Raman spectra (LRS). No X-ray diffraction peak of crystalline Eu2O3 can be found for all samples studied. The LRS show that two peaks at 998 and 1051 cm-1 assigned to two-dimensional surface europium-oxygen species appear at Eu2O3 content of 18.7 wt%. The peak at 1068 cm-1 due to the surface species and another peak at 342cm-1 due to crystalline Eu2O3 content start to appear for the sample with an Eu2O3 content of 36.5 wt%. The dispersity of Eu2O3 on the surface of amorphous Al2O3 were compared with that of α-Al2O3,η-Al2O3 and SiO2 gel. The results of these studies indicate that the structure of Eu2O3 dispersed onto the support surface depend on the structure of support and that there is an inductive effect of support on the structure of the Eu2O3.

New Method for Calculating Slit-Shaped Pore Size In Solids from Adsorption Isotherm

Assuming the pores in a porous solid to be slit-shaped,according to the principle of surface chemical thermody-namics,an equation for the calculation of pore size fromthe desorption branch of the isotherm of physical adsorp-tion of nitrogen on the porous solid at liquid nitrogentemperature is derived.The calculation results obtainedby different methods,namely,the classical method,BBmethod and the method of this paper,are compared.Comparison shows that the pore sizes d_T and d_H calculat-ed by the method of this paper and BB method respec-tively are larger than the pore size d_c calculated by theclassical method in the range 0【p/p_s【1;d_T】d_Hatp/p_s【0.71 and d_H】d_T at p/p_s】0.71;The results byBB method and the method of this paper tend to be thesame as that by the classical method while p/p_s ap-proaches 1.

Dynamic Simulation of Solid Adsorption Solar Refrigerator System with AC/CH₃OH as a Working Pair

Solid adsorption system, one of alternative refrigeration systems, is utilized to provide cold for refrigerator or air-conditioner and can be operated by assistance of solar heat. System performance study through computer usage to develop simulation program and simulate behaviors of system operation can give designed system which suits for user’s need. Also, the present study aims to develop dynamic simulation program of solid adsorption refrigeration system operated by solar assistance to simulate behaviors of system operation and its performance. Flat plate collectror is utilized to provide thermal energy for system’s adsorber and activated carbon/methanol is used to be a suitable working pair. Simulation procedure starts with various solar radiation intensities as input energy on solar collector and water is used as collector working fluid. Behavior of system operation can be considered to be 4 steps as isosteric heating, isobaric desorption, isosteric cooling and isobaric adsorption, respectively. This research studies the effect of varying solar radiation intensity on temperature, pressure of adsorber, adsorption ratio at each steps of system operated ranging from 6:00 am (the first day) to 6:00 am (the next day) and system performance which is defined as coefficient of performance, COP. In addition, the simulation result shows monthly average COP of 0.43 compared to a result of another previous research work under the same operating condition and the percentage error is 7.5%.

Methylene Blue Dye Adsorption onto Polyoxometalate Ionic Liquid Supported on Bentonite: Kinetic, Equilibrium and Thermodynamic Studies

The potential of polyoxometalate ionic liquid POM-IL supported on low-cost and available eco-friendly Saudi raw bentonite in the adsorption of MB cationic dye was investigated. For this purpose, TOAx[α-XW11O39]@Bentonite (X = Si, P;TOA = TetraOctylAmmonium), namely SWB and PWB were prepared and characterized by IR, XRD, XRF, SEM, TEM and BET. Batch adsorption experiments showed that SWB and PWB have higher adsorption capacity than the raw bentonite with an enhancement of about 37% for SWB. The adsorption capacities of both SWB and PWB improved with increasing contact time and temperature and decreased with higher salt concentration in solution. The pH is shown to have insignificant effect on the adsorption of MB onto SWB and PWB. This result is quite meaningful in the adsorption process application since it makes pH complicated adjustment of the discharged contaminated water before treatment unnecessary. The Kinetic study expressed that the pseudo-second-order model described the adsorption process better than the pseudo first order. The experimental isotherm data were found to fit the Langmuir model compared to the Freundlich model with a maximum adsorption capacity 277.78 mg/g and 113.6 for PWB and SWB respectively. The thermodynamic parameters illustrated that the adsorption process was favorable, spontaneous and endothermic.

A NEW MODEL FOR PHYSICAL ADSORPTION ON SOLID SURFACES

The principal assumptions about equivalence and energy distribution of the asdorption sites on solidsurfaces used by Langmuir for deriving the equation of monomolecular adsorption are generalized and anew physical adsorption model is proposed and tested with experimental data published in literature.Themodels of Langmuir,Freundlich,Temkin etc.are only the special cases.Assuming uniform density distributionof adsorption energy,the isotherm equation is given asn=K.1n[1+（bop）1/Mor n=K.1n[1+（boC）1/M]where n is the amount of adsorption per unit weight or area of solid p or C is tbe pressure of gas or the concen-tration of solution respectively.K,bo,M are constants with physical meanings as described in this paper.This equation can be used over wide range to quantitatively represent the five types of physical adsorptionclassified by Brunauer.

ADSORPTION OF SULFOXIDES ON SOLID FROM AQUEOUS SOLUTIONS——Ⅲ.THE ADSORPTION ON CARBON BLACK

The adsorption of decylmethylsulfoxide(DEMS)onto carbon black and the effects of temperature,salt(NaCl)and acid (HCl)have been measured.Typical two plateaux type adsorption isotherms were obtained.Applying the two step model of surfactant adsorption on solid/liquld interface and the general adsorption isotherm equation[9]the experimental results were interpreted qualitatively and quantitatively.

A solid-phase extraction approach for the identification of pharmaceutical–sludge adsorption mechanisms

It is important to understand the adsorption mechanism of chemicals and active pharmaceu-tical ingredients （API） on sewage sludge since wastewater treatment plants are the last barrier before the release of these compounds to the environment. Adsorption models were developed considering mostly hydrophobic API-sludge interaction. They have poor predictive ability, especially with ionisable compounds. This work proposes a solid-phase extraction （SPE） approach to estimate rapidly the API-sludge interaction. Sludge-filled SPE cartridges could not be percolated with API spiked mobile phases so different powders were tested as SPE sludge supports. Polytetrafluoroethylene （PTFE） was selected and tested at different PTFE/sludge ratios under eight different adsorption conditions with three API ionisable compounds. The PTFE/sludge mixtures with 50% or less sludge could be used in SPE mode for API sorption studies with methanol/water liquid phases. The results gave insights into API-sludge interactions. It was found that π-π, hydrogen-bonding and charge-charge interactions were as important as hydrophobicity in the adsorption mechanism of charged APIs on sludge.