Sorption of dyes from aqueous solutions onto fly ash.

Water Res

Faculty of Environmental Studies, University of Jan Evangelista Purkyne, Králova Výsina 7, 400 96 Ustí nad Labem, Czech Republic.

Published: December 2003

Brown coal fly ashes were tested as potentially low-cost sorbents for the removal of synthetic dyes from waters. It was shown that both basic (cationic) as well as acid (anionic) dyes can be sorbed onto the fly ash. The adsorption can be described by the multi-site Langmuir isotherm. The sorption capacities were in the range of 10(-1)-10(-3)mmol/g and did not differ significantly for basic and acid dyes. The dye sorption decreased in the presence of organic solvents (methanol, acetone). The presence of oppositely charged surfactants exhibited a pronounced effect on the dye sorption-low concentrations of the surfactant enhanced sorption, whereas high concentrations solubilized the dyes and kept them in solution. Inorganic salts exhibited only a minor effect on the dye sorption. The sorption of basic dyes increased at high pH values, whereas the opposite was true for acid dyes.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.watres.2003.08.011DOI Listing

Publication Analysis

Top Keywords

fly ash
8
acid dyes
8
dye sorption
8
sorption
6
dyes
6
sorption dyes
4
dyes aqueous
4
aqueous solutions
4
solutions fly
4
ash brown
4

Similar Publications

The purpose of this study is to solve the problem of ammonia (NH) release when modified magnesium slag (MMS) is used as coal mine backfill cementitious material, and to explore its chemical mechanism and put forward effective solutions. Uniaxial compressive strengths (UCS) hydration kinetics, scanning electron microscope (SEM), and thermogravimetric analysis-derivative thermogravimetry (TG-DTG), X-ray diffractometer (XRD) and other testing methods were used to study the evolution of the properties of MMS-based backfill material, which provided a scientific basis for the safe utilization of MMS. First, the chemical mechanism underlying the release of NH from MMS was identified, and it was confirmed that MgN and LiN are the main nitrogen sources.

View Article and Find Full Text PDF

To realize the comprehensive utilization of large amounts of high-ash coal slime and comprehensively understand the excellent performance of nutrient release and lead and cadmium adsorption of high-ash coal slime silicon composite materials, green and safe mild hydrothermal conditions (200 °C) were used to prepare the rich-rich coal slime. Zeolite/tobermorite composites (Z-TOBs) were used in this study. Batch adsorption tests and repeated extraction tests were used to determine whether silicon, potassium, and calcium nutrients of Z-TOBs have sustained release properties and are affected by pH.

View Article and Find Full Text PDF

Underestimated Industrial Ammonia Emission in China Uncovered by Material Flow Analysis.

Environ Pollut

January 2025

State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address:

Ammonia (NH) is crucial in fine particulate matter (PM) formation, but past estimations on industrial NH emissions remain highly uncertain. In this study, the flow of NH within air pollution control devices (APCDs) were investigated basing on material flow analysis with in-situ measurements of NH concentrations at the inlets and outlets of each APCD. Then, by combing emission factors updated with recent in-situ measurements and provincial-level activity data from statistical yearbooks and associated reports, NH emissions from various industrial sources, as well as their spatial distribution across China in 2020, were evaluated.

View Article and Find Full Text PDF

Municipal solid waste incineration fly ash (MSWIFA) is considered a hazardous solid waste, traditionally disposed by solidified landfill methods. However, solidified landfills present challenges with leaching heavy metals, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). To address this issue, this study examined two pretreatment methods for MSWIFA: sintering at 850℃ for 30 min and washing with three water baths (20 min each) at a 3:1 liquid-solid ratio.

View Article and Find Full Text PDF

This article systematically investigated the improvement effect of polypropylene fiber (PPF) on the mechanical and freeze-thaw properties of alkali-activated fly ash slag concrete (AAFSC) with high fly ash content and cured at room temperature. Fly ash and slag were used as precursors, with fly ash accounting for 80% of the total mass. A mixed solution of sodium hydroxide and sodium silicate was used as alkali activator, and short-cut PPF was added to improve the performance of AAFSC.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!