Utjecaj visokonaponskog plazma pražnjenja na razgradnju pesticida u vodenoj otopini

master's thesis

• Title (english): The effect of high voltage electrical discharge plasma on degradation of pesticides from aqueous solution
• Author: Toni Pintarić
• Mentor: Tomislava Vukušić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Food Processes Engineering); Zagreb
• Defense date and country: 2018-11-26, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Visokonaponsko plazma pražnjenje pripada u ekološki prihvatljive tehnike netermalnog procesiranja hrane. Cilj ovog rada bio je utvrditi potencijal tretmana hladnom plazmom u razgradnji pesticida (pirimetanila i fenheksamida). Tretman se provodio na vodenim otopinama pesticida u hibridnom plazma reaktoru u trajanju od 10, 20 i 30 min pri frekvencijama od 60, 90 i 120 Hz uz korištenje dušika, kisika, argona i zraka kao radnih plinova. Određivani su fizikalno-kemijski pokazatelji (temperatura, pH, električna provodnost) i radikalni spojevi (vodikov peroksid, nitrati i nitriti). Primjenom blisko-infracrvene spektroskopije određivane su strukturne promjene nastale tijekom tretmana. Koncentracija pesticida u otopinama mjerena je LC-MS/MS metodom. Najbolji rezultati razgradnje postignuti su tretmanom od 30 min, gdje je primjenom argona došlo do razgradnje 99,79% pirimetanila i 99,9% fenheksamida. Međutim kod tretmana od 10 min najbolji rezultat je postignut primjenom kisika kao radnog plina.

Abstract (english)

High voltage electrical discharge plasma is ecologically acceptable non-thermal food processing technique. The main goal of this research was to determine potential of non-thermal plasma discharge in decomposition of pesticides (pyrimethanil and fenhexamid). Treatment was conducted in pesticide solutions in the hybrid plasma reactor. Duration of treatments was 10, 20 and 30 min at frequencies of 60, 90 and 120 Hz with usage of nitrogen, argon, oxygen and atmospheric air as working gas. Physicochemical parameters (temperature, pH and electrical conductivity) and concentration of radical compounds were determined. Changes in structural composition of pesticides were determined using near-infrared spectroscopy. Concentration of pesticides in solution was measured using LC-MS/MS method. Best degradation results were accomplished in 30 min treatment with argon. Results showed that 99, 79% of pyrimethanil and 99, 9% of fenhexamid were degraded. In addition, the best results with were achieved after 10 minutes treatments with oxygen as working gas.

• Keywords: hibridna plazma; visokonaponsko pražnjenje; degradacija pesticida; pirimetanil; fenheksamid; bliska-infracrvena spektroskopija; LC-MS/MS
• Keywords (english): hybrid plasma; highvoltage electrical discharge; decomposition of pesticides; pyrimethnil; fenheamid; near-infrared spectroscopy; LC-MS/MS
• Language: croatian
• URN:NBN: urn:nbn:hr:159:084154
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2019-11-27 12:18:31