scholarly journals Removal of dexamethasone from aqueous solutions using modified clinoptilolite zeolite (equilibrium and kinetic)

2016 ◽  
Vol 13 (9) ◽  
pp. 2261-2268 ◽  
Author(s):  
S. N. Mohseni ◽  
A. A. Amooey ◽  
H. Tashakkorian ◽  
A. I. Amouei
Keyword(s):  
Aqueous Solutions ◽  
Clinoptilolite Zeolite ◽  
Modified Clinoptilolite

Effective adsorption of metal ions by modified clinoptilolite zeolite from simulated radioactive solution

2019 ◽  
Vol 319 (3) ◽  
pp. 1069-1081 ◽  
Author(s):  
Qun Luo ◽  
Dingwen Jiang ◽  
Dengyong Hou ◽  
Wei Chen ◽  
Xiuting Hu ◽  
...  
Keyword(s):  
Metal Ions ◽  
Adsorption Of Metal Ions ◽  
Clinoptilolite Zeolite ◽  
Modified Clinoptilolite

Removal of chromium(VI) from aqueous solutions using zeolites modified with HDTMA and ODTMA surfactants

Clay Minerals ◽  
2015 ◽  
Vol 50 (1) ◽  
pp. 103-115 ◽  
Author(s):  
Barbara Szala ◽  
Tomasz Bajda ◽  
Anna Jeleń
Keyword(s):  
Aqueous Solutions ◽  
Sorption Capacity ◽  
Exchange Capacity ◽  
Hexadecyltrimethylammonium Bromide ◽  
Column Studies ◽  
Maximum Sorption Capacity ◽  
Chromium Vi ◽  
Modified Clinoptilolite ◽  
The Impact ◽  
Influence Of Ph

AbstractThe removal of Cr(VI) from aqueous solutions under various conditions was investigated using a natural clinoptilolite and a synthetic zeolite derived from fly-ash (Na-P1), modified either with hexadecyltrimethylammonium bromide (HDTMA) or octadecyltrimethylammonium bromide (ODTMA). The study was focused mainly on the impact of the properties of the zeolite on the sorption capacity, the sorption mechanism, the influence of pH and the durability of the immobilization. The zeolites were modified with HDTMA and ODTMA surfactants up to 100% and 120% of their external cation exchange capacity. Batch and column studies were conducted to evaluate the influence of pH and the initial Cr(VI) concentration on their efficiencies for removing chromates. The organo-zeolites show a significant ability to remove Cr(VI) from aqueous solutions. The amount of Cr(VI) removed by organo-clinoptilolite and organo-zeolite Na-P1 is greater at low pH values, whereas the sorption efficiency decreased with increasing pH. Sorption of Cr(VI) was more efficient with the HDTMA-modified organo-clinoptilolite (150 mmol Cr(VI)/kg) than the ODTMA-modified clinoptilolite (132 mmol Cr(VI)/kg). The maximum sorption capacity was obtained with the 1.2 × ECEC ODTMA-modified clinoptilolite (237 mmol Cr(VI)/kg). The organozeolites Na-P1 adsorbed Cr(VI) from aqueous solutions more effectively and were much more durable than the organo-clinoptilolites.

scholarly journals Supplementary research of clinoptilolite-rich tuff composites after adsorption trials using the XPS technique

2006 ◽  
Vol 4 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Eva Chmielewská ◽  
Wlodzimierz Tylus ◽  
Marcela Morvová
Keyword(s):  
Organic Carbon ◽  
Aqueous Solutions ◽  
Photoelectron Spectroscopy ◽  
External Surface ◽  
Zeolite Surface ◽  
X Ray ◽  
Surface Modified ◽  
Modified Clinoptilolite

AbstractThe paper deals with fabrication of carbonized and hydrophobized clinoptilolite-rich tuff using organic carbon rich substances, here particularly starch and waste vegetable residues, which were pyrolytically combusted and covered the external zeolite surface. Hydrophobization of the zeolite external surface was accomplished by octadecylammonium surfactant. Both surface modified clinoptilolite-rich tuffs were tested and compared with each other with regard to removal of organic (phenol) and inorganic (chromate, arsenate) pollutants from aqueous solutions. These elaborated composites with surface adsorbed pollutant species were analysed by X-ray photoelectron spectroscopy (XPS).

scholarly journals Adsorption of Cr(VI) by Natural Clinoptilolite Zeolite from Aqueous Solutions: Isotherms and Kinetics

2017 ◽  
Vol 19 (3) ◽  
pp. 106-114 ◽  
Author(s):  
Sahand Jorfi ◽  
Mohammad Javad Ahmadi ◽  
Sudabeh Pourfadakari ◽  
Nematollah Jaafarzadeh ◽  
Reza Darvishi Cheshmeh Soltani ◽  
...  
Keyword(s):  
Experimental Data ◽  
Aqueous Solutions ◽  
Contact Time ◽  
Chromium Concentration ◽  
Order Kinetic ◽  
Operational Parameters ◽  
Simple Modification ◽  
Adsorbent Dosage ◽  
Clinoptilolite Zeolite ◽  
Natural Clinoptilolite

Abstract The main aim of this study was to evaluate the efficiency of natural zeolite for Cr(VI) removal from aqueous solutions. Following simple modification of adsorbent, the effect of operational parameters including pH (2–10), adsorbent dosage (2–20 g/L), contact time (5–150 min) and Cr(VI) concentration (10–50 mg/L) were studied according to one-factor-at-a-time procedure. The maximum Cr(VI) removal of 99.53% was obtained at initial pH of 2, contact time of 30 min, adsorbent dosage of 8 g/L and initial chromium concentration of 10 mg/L. The Freundlich isotherm was best fitted with experimental data (R2 = 0.951). Also, type 1pseudo second order kinetic model showed the most correlation (R2 = 1) with the experimental data. According to obtained results, it can be concluded that the application of clay-like adsorbents such as natural clinoptilolite zeolite can be considered as an efficient alternative for final treatment of effluents containing Cr(VI).

Sign in / Sign up

Export Citation Format

Share Document