Construction of hydrophobic channels on Cu(I)-MOF surface to improve selective adsorption desulfurization performance in presence of water

Author(s):  
Yiping Guo ◽  
Wei Xie ◽  
He Li ◽  
Jianping Li ◽  
Jun Hu ◽  
...  
2020 ◽  
Vol 379 ◽  
pp. 122356 ◽  
Author(s):  
Diana Iruretagoyena ◽  
Kagiso Bikane ◽  
Nixon Sunny ◽  
Huiqiang Lu ◽  
Sergei G. Kazarian ◽  
...  

2020 ◽  
Author(s):  
Bo-Long Jiang ◽  
Nan Jiang ◽  
You-Xin Chang

Abstract Abstract A bimetal-exchanged NaY zeolite (Cu(I)-Y(III)-Y) with a desirable adsorptive desulfurization (ADS) performance was prepared and characterized by means of X-ray diffraction, specific surface area measurements, X-ray fluorescence spectrometer, X-ray photoelectron spectroscopy, thermal gravity analysis and Fourier transform infrared spectroscopy. The effect of Y(III) ions on ADS in the presence of the xylenes was investigated. Results indicated that the ADS performance of Y(III)-Y is higher than that of most reported CeY. The Y(III)-based Cu(I)-Y(III)-Y demonstrated the higher breakthrough loading than those of reported Ce(III)/Ce(IV)-based transition metal Y zeolites, showing that Y(III) ions play a promoting role in improving the ADS selectivity. For Cu(I)-Y(III)-Y, a new strong S-M interaction (S stands for sulfur, while M stands for metal) active site was formed, which might be caused by the synergistic effect between Cu(I) and Y(III). The Cu(I)-Y(III)-Y, which combined the advantages of Cu(I)-Y and Y(III)-Y, is a kind of promising adsorbent. The breakthrough loading decreased in the order of Cu(I)-Y(III)-Y > Y(III)-Y > Cu(I)-Y, and the effect of xylene isomers on the sulfur removal was in the order of ortho-xylene > meta-xylene > para-xylene, which exhibited the same trend with the bond order of xylenes.


Author(s):  
Muwafaq Mohammed Yahya ◽  
Hussein Qasim Hussein

This work was conducted to study the effect of selective adsorption on removal of sulfur  compounds  from  Iraqi  heavy  naphtha  from  Al-Dura refinery  by using  molecular  sieve (13X)  in a fixed-bed column and  it was be run out at 1.5–6.0h-1 LHSV, 15–30 gr  weight of molecular sieve (13X), 600–1650ppm sulfur concentration in the feedstock ,  the adsorption  temperature  was  25oC and 40oC.  The best operating conditions for removing sulfur compounds was 3.0 h-1 LHSV, 20 gr molecular sieve bed weight and 25oC temperature, where the sulfur content in heavy naphtha was reduced from nearly 600 ppm to less than 1 ppm (by weight). Regeneration steps was thermally took place by hot air flow in a range from 16.66 – 25 liter / min and temperature range from 200–350oC, the best desorption conditions for (85.8%) weight percent removing was at 16.66 liter / min air flow and 350 oC.


Author(s):  
J.A. Panitz

The first few atomic layers of a solid can form a barrier between its interior and an often hostile environment. Although adsorption at the vacuum-solid interface has been studied in great detail, little is known about adsorption at the liquid-solid interface. Adsorption at a liquid-solid interface is of intrinsic interest, and is of technological importance because it provides a way to coat a surface with monolayer or multilayer structures. A pinhole free monolayer (with a reasonable dielectric constant) could lead to the development of nanoscale capacitors with unique characteristics and lithographic resists that surpass the resolution of their conventional counterparts. Chemically selective adsorption is of particular interest because it can be used to passivate a surface from external modification or change the wear and the lubrication properties of a surface to reflect new and useful properties. Immunochemical adsorption could be used to fabricate novel molecular electronic devices or to construct small, “smart”, unobtrusive sensors with the potential to detect a wide variety of preselected species at the molecular level. These might include a particular carcinogen in the environment, a specific type of explosive, a chemical agent, a virus, or even a tumor in the human body.


2004 ◽  
Vol 4 (5-6) ◽  
pp. 335-341 ◽  
Author(s):  
Jae-Kyu Yang ◽  
Yoon-Young Chang ◽  
Sung-Il Lee ◽  
Hyung-Jin Choi ◽  
Seung-Mok Lee

Iron-coated sand (ICS) prepared by using FeCl3 and Joomoonjin sand widely used in Korea was used in this study. In batch adsorption kinetics, As(V) adsorption onto ICS was completed within 20 minutes, while adsorption of Pb(II), Cd(II), and Cu(II) onto ICS was slower than that of As(V) and strongly depended on initial pH. At pH 3.5, ICS showed a selective adsorption of Pb(II) compared to Cd( II) and Cu(II) . However, above pH 4.5, near complete removal of Pb(II), Cd(II), and Cu(II) was observed through adsorption or precipitation depending on pH. As(V) adsorption onto ICS occurred through an anionic-type and followed a Langmuir-type adsorption behaviour. In column experiments, pH was identified as an important parameter in the breakthrough of As(V). As(V) breakthrough at pH 4.5 was much slower than at pH 9 due to a strong chemical bonding between As(V) and ICS as similar with batch adsorption behaviour. With variation of ICS amounts, the optimum amount of ICS at pH 4.5 was identified as 5.0 grams in this research. At this condition, ICS could be used to treat 200 mg of As(V) with 1 kg of ICS until 50 ppb of As(V) appeared in the effluent. In this research, as a new treatment system, ICS can be potentially used to treat As(V) and cationic heavy metals.


2019 ◽  
Vol 25 (34) ◽  
pp. 3633-3644
Author(s):  
Nasrullah Shah ◽  
Saba Gul ◽  
Mazhar Ul-Islam

: Core-shell polymers represent a class of composite particles comprising of minimum two dissimilar constituents, one at the center known as a core which is occupied by the other called shell. Core-shell molecularly imprinting polymers (CSMIPs) are composites prepared via printing a template molecule (analyte) in the coreshell assembly followed by their elimination to provide the everlasting cavities specific to the template molecules. Various other types of CSMIPs with a partial shell, hollow-core and empty-shell are also prepared. Numerous methods have been reported for synthesizing the CSMIPs. CSMIPs composites could develop the ability to identify template molecules, increase the relative adsorption selectivity and offer higher adsorption capacity. Keen features are measured that permits these polymers to be utilized in numerous applications. It has been developed as a modern technique with the probability for an extensive range of uses in selective adsorption, biomedical fields, food processing, environmental applications, in utilizing the plant's extracts for further applications, and sensors. This review covers the approaches of developing the CSMIPs synthetic schemes, and their application with special emphasis on uses in the biomedical field, food care subjects, plant extracts analysis and in environmental studies.


The influence of small amounts of dissolved foreign substances on the growth of crystals from saturated solutions has been the subject of much investigation. Usually the added substances have been electrolytes. Dyestuffs have not been neglected, but with some few exceptions comparatively little attention has been given to the effect of non-ionized water-soluble electrolytes such as gelatine or dextrine. As a rule, the presence of the foreign substances is found to cause the crystals to assume a different habit. Whenever this occurs the absorption must have occurred on certain crystal-faces in preference to others, but, although the added material is active by virtue of its close attachment to such faces, it is rarely found to be incorporated into the solid to any great extent. The growing crystals appear to reject the impurity—thrusting it outwards as the growth advances. The action of water-soluble colloids on the halides and certain other salts of lead is exceptional in several ways. Although when such colloids are present in small concentrations one can generally observe a modification of habit, at higher concentrations there may be little selective adsorption, and the result may be a rounded crystal on which no plane faces at all can be distinguished, as if the forces by which atoms are attracted to the structure had been equalized in every direction.


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