scholarly journals Selective Sorption of Ge(IV) Oxoanion by Composite Sorbent Based on Hydrous Oxide of Zirconium

2021 ◽  
pp. 10-14
Author(s):  
Eva Mištová ◽  
Helena Parschová ◽  
Luděk Jelínek

In this work, a composite sorbent based on hydrous zirconium oxide was used for selective removal of Ge(IV) oxoanions. Experiments were carried out by batch equilibrium tests and dynamic column sorption. The best sorption capacity was reached at the pH of 9, when about 4.3 g of Ge by liter of composite. The negative effect of the concentration of chlorides and sulfates was observed when their concentration was higher than 500 mg/L. The optimal specific solution flow rate for sorption by ZrO2-PAN sorbent was determined to be 6 BV/h. For regeneration, 15 BV of 0.5 M HCl solution saturated with NaCl was used.

1988 ◽  
Vol 3 (3) ◽  
pp. 561-562 ◽  
Author(s):  
Li-Min Tau ◽  
Ram Srinivasan ◽  
Robert J. De Angelis ◽  
Tim Pinder ◽  
Burtron H. Davis

The pH of the solution in contact with a hydrous zirconium oxide plays a dominant role in determining the crystal phase, tetragonal or monoclinic, in the calcined material. The substitution of low concentrations of hafnium for zirconium destabilizes the tetragonal phase so that only the monoclinic phase is formed; the amount of Hf required for destabilization depends upon the pH used for the preparation of the hydrous oxide. While this study has defined a phenomenon, the results do not permit a definition of the mechanism for it.


2020 ◽  
Vol 71 (1) ◽  
pp. 1-12
Author(s):  
Salman H. Abbas ◽  
Younis M. Younis ◽  
Mohammed K. Hussain ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor ◽  
...  

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.


2019 ◽  
Vol 12 (3) ◽  
pp. 135-143 ◽  
Author(s):  
Fatin Abdul_kareem Ashoor ◽  
Amer D. Zmat ◽  
Muthanna H. AlDahhan

A lab scale pellet reactor (PR) was designed and fabricated to carry out extensive investigations on the removal efficiency of the hardness of groundwater.  The groundwater of 2200 – 2600 mg/L hardness was collected from Abdulla Ibnalhassan wells area located at the west desert of Al-Shinafiyah district (70 km to the southwest of Al-Dewaniyah city, Iraq). Both hydrodynamic parameters of the pellet reactor (porosity and fluidized bed height) and the parameters of calcium carbonate crystallization process (calcium carbonate equilibrium, pellet size, and density) were modeled and compared with the experimental results of the lab scale pellet reactor. The comparison showed that fair agreement between modeled and measured results was observed. The removal efficiency of both calcium and magnesium ions were 62.5-99% and 83-99% respectively. The removal efficiency was found to be strongly dependent on pH and the ratio of NaOH solution flow rate to the groundwater flow rate in the pellet reactor.


1982 ◽  
Vol 5 (1) ◽  
pp. 33-36 ◽  
Author(s):  
R. Scholtens ◽  
J. Scholten ◽  
H.W.M. de Koning ◽  
J. Tijssen ◽  
H.W.M. ten Hoopen ◽  
...  

Patients suffering from primary hyperoxaluria show elevated plasma concentrations of oxalic acid and glyoxylic acid. The in vitro adsorption of these compounds onto activated charcoal, a series of neutral and ion exchange resins and onto hydrous zirconium oxide has been investigated. Hydrous zirconium oxide was the most effective sorbent studied for the removal of both oxalic acid and glyoxylic acid. In batch experiments, the zirconium oxide was capable of binding 5.5 μ mol oxalic acid and 8 μ mol glyoxylic acid per gram sorbent using 0.5 gram sorbent and 50 ml of solutions with initial concentrations of 100 μ mol. L−1 and an ionic composition resembling that of plasma. Recirculation of 2 L of the same solutions through 12 gram of a mixture of hydrous zirconium oxide and alumina for 6 hours at a flow rate of 12 ml.min−1, resulted in a final concentration of 70 μ mol. L−1 of oxalic acid and 50 μ mol. L−/ of glyoxylic acid.


Sign in / Sign up

Export Citation Format

Share Document