scholarly journals TiO2 Decorated Low-Molecular Chitosan a Microsized Adsorbent for a 68Ge/68Ga Generator System

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3185
Author(s):  
Jun-Young Lee ◽  
Pyeong-Seok Choi ◽  
Seung-Dae Yang ◽  
Jeong-Hoon Park

We report column material for a 68Ge/68Ga generator with acid resistance and excellent adsorption and desorption capacity of 68Ge and 68Ga, respectively. Despite being a core element of the 68Ge/68Ga generator system, research on this has been insufficient. Therefore, we synthesized a low molecular chitosan-based TiO2 (LC-TiO2) adsorbent via a physical trapping method as a durable 68Ge/68Ga generator column material. The adsorption/desorption studies exhibited a higher separation factor of 68Ge/68Ga in the concentration range of HCl examined (0.01 M to 1.0 M). The prepared LC-TiO2 adsorbent showed acid resistance capabilities with >93% of 68Ga elution yield and 1.6 × 10−4% of 68Ge breakthrough. In particular, the labeling efficiency of DOTA and NOTA, by using the generator eluted 68Ga, was quite encouraging and confirmed to be 99.65 and 99.69%, respectively. Accordingly, the resulting behavior of LC-TiO2 towards 68Ge/68Ga adsorption/desorption capacity and stability with aqueous HCl exhibited a high potential for ion-exchange solid-phase extraction for the 68Ge/68Ga generator column material.

1982 ◽  
Vol 14 (12) ◽  
pp. 107-125 ◽  
Author(s):  
Roland Wollast

A comparison of the concentration of dissolved and of particulate heavy metals in the aquatic system indicates that these elements are strongly enriched in the suspended matter. The transfer between the aqueous phase and the solid phase may be due to dissolution-precipitation reactions, adsorption-desorption processes or biological processes. When these processes are identified, it is further possible to develop mathematical models which describe the behaviour of these elements. The enrichment of heavy metals in the particulate phase suspended or deposited and in aquatic organisms constitutes a powerful tool in order to evaluate sources of pollution.


2019 ◽  
Vol 31 (11) ◽  
pp. 2527-2531
Author(s):  
St. Fauziah ◽  
N.H. Soekamto ◽  
P. Budi ◽  
P. Taba

Molecularly imprinted polymers (MIP) as an adsorbent has been synthesized using β-sitosterol as molecule template on free radical polymerization reaction. The capacity and selectivity of the adsorption from MIP to β-sitosterol was studied in this study. The β-sitosterol concentration in the adsorption-desorption test and the MIP selectivity test were analyzed by UV-visible and HPLC. The MIP obtained from the synthesis results in a high adsorption capacity. Based on the Freundlich adsorption isothermal equation, the adsorption capacity (k) was found to be 1.24 mg/g. The MIP can adsorb 100 % β-sitosterol while cholesterol was only 3 %. The MIP is most selective to β-sitosterol, therefore, has high potential to apply as adsorbent at solid phase extraction method to isolate β-sitosterol from sample extract.


Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5652
Author(s):  
Oscar Banos ◽  
Sven Ohmann ◽  
Cornelia Breitkopf

Adsorption processes are of great interest in catalysis, material separation, and thermal management. In recent decades, adsorbents have been further investigated because of their applications in adsorption refrigeration, heat pumps, and thermal energy storage. Thus, there is an increasing need to determine the macroscopic properties of the adsorbent, specifically their adsorption/desorption capacity and speed, because these two factors determine the power and size of the corresponding adsorber. Many designs have been proposed, but there is still not a generally adopted technology for the analysis of those properties. In this paper, a novel instrument is described, which is capable of determining the macrokinetic properties of an adsorbent composite, with better control and higher accuracy than gravimetric, volumetric, or barometric installations, and lower price and complexity than spectroscopic installations. The design of the installation is detailed, highlighting the main challenges and critical factors. The two working modes of the installation are described, and one example is provided and analyzed for each of them.


2013 ◽  
Vol 16 (2) ◽  
pp. 107-114
Author(s):  
. Marsi ◽  
. Sabaruddin

Ultisols and Inceptisols were used to investigate the adsorption-desorption capacity of P and the effect of organic matter on the dynamics of P availability in tropical acid soils. The experiment consisted of two sub-experiments. Sub-experiment I was to study the adsorption-desorption capacity of Ultisols, Fresh-water lowland Inceptisols, and tidal-swamp Inceptisols. Therefore, surface soils (0 to 30 cm) of each tested soil were treated with 0, 10, 20, 30, 40, 60, 80, 100, 120, 140, 170, and 200 mg P kg-1 of soil. Sub-experiment II was to study the effects of organic matterapplication (0, 5, 10, and 15 Mg ha-1) on the dynamics of available P following 60d incubation under room temperature.P fertilizer application significantly affected water soluble-P (WSP) (p<0.01) and soil available P-Bray and Kurtz No. 1 (BKP) (p<0.01) in the three tested soils. The different response of both WSP and BKP confirmed that the soils tested in the current experiment had different soil P buffering capacity in the order of Tidal-lowlandInceptisol>Upland Ultisol>fresh-water Lowland Inceptisol. OM application increased the BKP in all tested soils as compared to the control. Differences in pattern of soil available P dynamics over time were detected between upland soil and two lowland soils used in the current experiment.Keywords: Adsorption-desorption, Inceptisols, organic matter, Ultisols


2015 ◽  
Vol 3 (1) ◽  
pp. 31
Author(s):  
Dwinna Rahmi

 ABSTRACT A syringe-based sample pretreatment tool, named herein “chelating monolith”, has been developed for simple and facile solid phase microextraction (SPME) of trace elements in natural waters. The monolith was directly prepared within the confines of a commercially available syringe filter tip by a two-step process: 1) in situ polymerization of glycidyl methacrylate (GMA) with ethylene glycol dimethacrylate (EDMA) and 2) subsequent modification with iminodiacetate (IDA) via ring opening reaction of epoxide. The composition of porogenic solvent was first optimized to make a rigid-porous material that has high permeability and ample surface area as much as possible. Then, the pH and concentration of the IDA modification solution were examined to obtain higher chelating capacity. The metal adsorption properties of the obtained chelating monolith were evaluated through an adsorption/desorption experiment. After optimization of some parameters such as sample solution pH, eluent concentration and the volume, good recoveries of more than 80% were obtained for 28 elements including REEs, Fe, Co, Ni, Cu, Zn, Ga, Pb and Th in a single extraction step. The proposed SPME method was validated through the analysis of river water certified reference material (CRM: JSAC 0301-1) Keywords: Solid phase microextraction; syringe filter; chelating monolith; iminodiacetate; ICP-MS


2011 ◽  
Vol 311-313 ◽  
pp. 1491-1495
Author(s):  
Li Min Wang ◽  
Ying Hua Li ◽  
Wei Wei

A novel ion-imprinted organic-inorganic hybrid sorbent was synthesized and characterized by FT-IR and nitrogen gas adsorption-desorption. The adsorption property and selective recognition ability of the imprinted sorbents for the lead ion were studied. Results showed that the uptake capacities and selectivity coefficients of the double imprinted sorbent were much higher than that of the non-imprinted sorbent. The adsorption capacity of the double imprinted sorbent is 545.6 mg•g-1. The largest relative selectivity coefficient between Pb (II) and Cd (II) was 192. This results suggested that the new sorbent can be used as effective solid-phase material for the selective preconcentration and separation of Pb (II) in environmental water samples.


Author(s):  
M.V. Galaburda ◽  
V.M. Bogatyrov ◽  
W. Tomaszewski ◽  
O.I. Oranska ◽  
M.V. Borysenko ◽  
...  

2015 ◽  
Vol 723 ◽  
pp. 481-484
Author(s):  
Xiao Dong Li

SBA-15 molecular sieve owned the characteristic of uniform nanoscale channels, large pores, thick walls and high hydrothermal stability. It has the potential foreground as adsorption, separation, catalysis and new type host-guest nanocomposite materials. In this paper, SBA-15 molecular sieve was synthesized in acidic medium by hydrothermal method using triblock copolymers (EG20PG40EG20) as template, tetraethoxysilane as silica resource. Semiconductor material AgI was incorporated into the mesoporous channels of the SBA-15 molecular sieve by solid phase thermal diffusion method and the (SBA-15)-AgI nanocomposites materials were prepared. The products were characterized by means of powder X-ray diffraction, low-temperature nitrogen adsorption-desorption technique at 77 K and luminous properties were studied. The results showed that AgI went into the channels of the SBA-15, the materials (SBA-15)-AgI remained the highly ordered two-dimensional hexagonal. However, the crystalline was decreased to some degree, the pore volume, pore size and the surface area decreased to some extent compared to those of the SBA-15 molecular sieve. It was found by luminous studies that the energy band gap of the (SBA-15) -AgI composite material is very high and radiation process is very strong. The composite materials possess very good luminous performance and can be hopefully acted as luminous materials.


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