Adsorption of pollutants from colored wastewaters after natural wool dyeing

Alenka Ojstršek (Author), Primož Vouk (Author), Darinka Fakin (Author)

Abstract

The presented study assesses the efficiency of selected adsorbents, zeolite 4A in two particle sizes and pelletized activated carbon (AC), for the potential removal of color, chemical oxygen demand (COD), total organic carbon (TOC) and metals from wastewaters after natural wool dyeing. Firstly, the natural coloring compounds were extracted from dried common walnut (Juglans regia) leaves and used further for exhaustion dyeing of wool fibers, together with three different metallic salts in two concentrations (meta-mordanting). Effluents with higher mordant concentration were additionally treated according to a shake-flask adsorption experiment. The obtained results revealed efficient removal of exceeded metallic ions by zeolite (up to 94.7%), on account of their superior ion exchange capability as compared to AC. The zeolites also reduced turbidity and electrical conductivity significantly. On the other hand, AC was more efficient for the reduction in organic pollution, COD up to 96% and TOC up to 95%, due to its higher specific surface area and total pore volume, and, thus, higher potential for adsorption of different compounds in comparison to 4A. All three proposed adsorbents lowered wastewaters’ coloration remarkably, up to 78% (AC) and up to 71% (4A), depending on the type of effluent/mordant and inspected wavelength; although, the spectral absorbance coefficient (SAC) values remained highly above the limit values for discharge of wastewaters into watercourses.

Keywords

barvanje volne;naravna barvila;čiščenje odpadnih vod;razbarvanje;zmanjšanje težkih kovin;adsorpcija;wool dyeing;natural dyes;wastewater treatment;decoloration;heavy metals’ reduction;adsorption;

Data

Language:	English
Year of publishing:	2022
Typology:	1.01 - Original Scientific Article
Organization:	UM FS - Faculty of Mechanical Engineering
Publisher:	MDPI AG
UDC:	677.017:502/504
COBISS:	97969155
ISSN:	1996-1944
Views:	0
Downloads:	3
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Slovenian
Secondary keywords:	barvanje volne;naravna barvila;čiščenje odpadnih vod;razbarvanje;zmanjšanje težkih kovin;adsorpcija;
Type (COBISS):	Article
Pages:	14 str.
Volume:	ǂVol. ǂ15
Issue:	ǂiss. ǂ4 (1488)
Chronology:	Feb. 2022
DOI:	10.3390/ma15041488
ID:	26084212