Influence of Zinc and Humic Acids on Dye Adsorption from Water by Two Composts

Area of Science:

• Environmental Science
• Environmental Chemistry
• Materials Science

Background:

• Textile dye removal from wastewater is crucial.
• Low-cost biosorbents are sought for dye remediation.
• Contaminant effects on biosorbent performance need investigation.

Purpose of the Study:

• To assess compost biosorbents for textile dye removal.
• To investigate the impact of zinc and dissolved organic matter on dye adsorption.
• To compare municipal solid waste compost and pine bark compost performance.

Main Methods:

• Batch adsorption experiments were conducted.
• Three dyes (Basic Violet 10, Acid Blue 113, Direct Blue 71) were tested.
• Composts were evaluated in the presence of Zn or humic acids.

Main Results:

• Dye adsorption followed the order: Basic Violet 10 > Acid Blue 113 > Direct Blue 71.
• Freundlich model described sorption well; Langmuir model was less consistent.
• Pine bark compost showed higher capacity for cationic dyes; municipal compost favored anionic dyes.
• Zinc and dissolved organic matter did not significantly reduce dye adsorption.

Conclusions:

• Composts are viable, low-cost biosorbents for textile dyes.
• Contaminants like Zn and dissolved organic matter do not hinder dye adsorption by composts.
• Study findings support the use of composts for real textile wastewater treatment.