Wyniki wyszukiwania - BazTech

1

Sorption isotherm study of manganese removal from aqueous solutions by natural and MnO2-coated zeolite

Demcak Stefan, Kovacova Zdenka, Balintova Magdalena, Fazekas Juraj, Zinicovscaia Inga

Environment Protection Engineering

|

2021

|

Vol. 47, nr 3

17--24

EN

The applicability of the natural and MnO2-coated zeolite as sorbent for the removal of Mn(II) from synthetic solutions has been investigated. Batch experiments were carried out to determine the influence of pH and Mn(II) concentration on the sorption process. A maximum removal efficiency (98.9%) was observed for modified zeolite with the concentration of 10 mg/dm3 of manganese in solution. The equilibrium data showed a very good correlation for both Langmuir and Freundlich sorption models and this suggests both monolayer adsorption and a heterogeneous surface existence. Maximum sorption capacity calculated from the Langmuir model constituted 5.57 mg/g for natural zeolite and 13.41 mg/g for modified zeolite.

2

The removal of sulphate ions from model solutions and their influence on ion exchange resins

Demcak Stefan, Balintova Magdalena, Holub Marian

Ekonomia i Środowisko

|

2020

|

nr 2

59--70

EN

There is a growing tendency for industries around the globe to diminish the contents of pollutants in industrial wastewaters to an acceptable level. Conventional methods are unfavourable and economically unacceptable, especially for large volumes of wastewaters with a high content of undesirable compounds. In contrast, ion–exchange is a very powerful technology capable of removing contamination from water. This paper analyses a study of ion exchange in Amberlite MB20 and Purolite MB400 resins after sulphate removal from a model solution. For the characterisation of ion exchange in resins, infrared spectroscopy was used. The IR spectra of both ion exchange resins show a similar composition after adsorption. Experiments that are due to this same used matrix in producing. The efficiency of sulphate ion removal and pH changes were also measured. Amberlite MB20 has proven to be a suitable ion exchange resin due to its high effi ciency (about 86%) for the removal of sulphates from solutions with initial concentrations of 100 and 500 mg.L-1, respectively.

3

Removal of copper, zinc and iron from water solutions by spruce sawdust adsorption

Kovacova Zdenka, Demcak Stefan, Balintova Magdalena

Ekonomia i Środowisko

|

2019

|

nr 3

64--74

EN

The water pollution by toxic elements is one of the major problems threatening human health as well as the quality of the environment. Sorption is considered a cost-effective method that is able to effectively remove heavy metals. During past few years, researches have been researching usage of low-cost adsorbents like bark, lignin, chitosan peat moss and sawdust. This paper deals with the study of copper, zinc and iron adsorption by adsorption of spruce sawdust obtained as a by-product from locally used wood. Raw spruce sawdust was used to remove heavy metal ions from the model solutions with ion concentration of 10 mg/L during 24 hours or 5, 10, 15, 30, 45, 60, 120 min, respectively. Fourier-transform infrared spectroscopy was applied to determine functional groups of sawdust. Sorption efficiency was higher than 67% in short-time experiments and higher than 75% for one day experiments in all tested cations.