Potential of bioash for removal of the herbicide terbuthylazine from the aquatic matrix

master's thesis

• Author: Gracijela Maltašić
• Mentor: Gabrijel Ondrašek (mentor)
• Mentor: Sanja Stipičević (komentor)
• Committee member: Gabrijel Ondrašek (predsjednik povjerenstva)
• Committee member: Klara Barić (član povjerenstva)
• Committee member: Sanja Stipičević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Soil Amelioration); Zagreb
• Defense date and country: 2021-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Terbuthylazine (TBA) is one of the most used herbicides in agriculture, forestry, and
transportation sectors, particularly since 2007 when widely used atrazine has been banned.
Soon after its pre-emergence application, TBA residues can be spread from soil to the entire
aquatic environment. Biodegradation of TBA in the soil is much faster than its abiotic
degradation in water, where it is proved to be relatively persistent and harmful to a range of
aquatic organisms. Therefore, the efficiency of fly ash (FA)-treatment of watercourse samples
fortified with TBA was tested in laboratory conditions. Deciduous hardwood-derived FA was
produced in a cogeneration plant facility and subjected to in-depth characterization using
SEM and XRD methods. The results showed that the addition of 1% (w/v) of the finest FA
fraction, with a nano-to-micro-sized structure and alkaline Ca/Mg/Si-enriched mineralogy,
can reduce the TBA half-life in the watercourse sample by more than 30-fold. The TBA
dissipation in FA-amended water was well described with the first-order kinetics (R²>0.98).
TBA and its environmentally relevant degradation product desethylterbuthylazine (DET)
were not detected in the water sample 48 hours after the FA addition, whereas nearly 80% of
TBA was found in the untreated sample. The XPS analysis of post-treated FA suggested a
plausible involvement of O, Ca, K, Mg, and Si in TBA adsorption. A basis for the
development of innovative FA-based polymers targeted to decontamination aquatic
ecosystems loaded with TBA and other hazardous (agro)chemicals were proposed.

• Keywords: Terbuthylazine; Surface water; Wood biomass; Fly ash; Dissipation
• Language: english
• URN:NBN: urn:nbn:hr:204:383946
• Study programme: Title: Environment, Agriculture and Resource Management; Study programme type: university; Study level: graduate; Academic / professional title: Master of Engineering in Agriculture (Master of Engineering in Agriculture)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-02-01 12:56:36