Sorpcija diazo bojila na lebdećem pepelu

master's thesis

• Title (english): Sorption of diazo dyes on fly ash
• Author: Zrinka Šokčević
• Mentor: Šime Ukić (mentor)
• Committee member: Šime Ukić (predsjednik povjerenstva)
• Committee member: Lidija Ćurković (član povjerenstva)
• Committee member: Sebastijan Orlić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2015-09-23, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry; Analytic Chemistry

Abstract

Cilj ovog rada bio je ispitati primjenu lebdećeg pepela kao potencijalnog sorbensa za uklanjanje toksičnog i kancerogenog diazo bojila (kongo crvene) iz vodene otopine. U šaržnim uvjetima ispitano je uklanjanje bojila kongo crvene uporabom lebdećeg pepela variranjem početne koncentracije bojila, vremena kontakta i temperature procesa. Za analizu ravnotežnih podataka na različitim temperaturama korištene su Langmuirova, Freundlichova i Dubinin-Radushkevich izoterma. Tri kinetička modela (model pseudo-prvog reda, model pseudo-drugog reda i unutarčestična difuzija) su upotrebljana kako bi se predvidjele konstante brzine sorpcije. Utvrđeno je da sorpcija slijedi kinetički model pseudo-drugog reda te da je unutarčestična difuzija jedan od koraka koji određuju brzinu procesa sorpcije. Izračunati su i termodinamički parametri (slobodna energija, entalpija i entropija). Dobivene negativne vrijednosti slobodne energije, entalpije i entropije ukazuju na to da je sorpcija spontana, egzotermna i stabilna.

Abstract (english)

The goal of this work was investigation of application of fly ash as a sorbent for removal of toxic and cancerogenic diazo dye (congo red) from aqueous solutions. Batch sorption process was performed in the order to examine removal of congo red dye using fly ash by variation of the initial dye concentration, contact time and temperature of the process. Langmuir, Freundlich and Dubinin-Radushkevich isotherms were used to analyze the equilibrium data at different temperatures. A linear method was used for comparing the best fitting of the isotherms. The equilibrium data could be well described by the Langmuir isotherm. Three kinetic models (pseudo-first-order, pseudo-second-order and intra-particle diffusion) were used to predict the adsorption rate constants. The adsorption kinetic was found to follow pseudo-second-order rate kinetic model and the intra-particle diffusion was one of the rate determining steps. Thermodynamic parameters (free energy, enthalpy, and entropy) were calculated. The negative values of free energy, enthalpy and entropy suggested that the sorption was spontaneous, exothermic and stable.

• Keywords: sorpcija; lebdeći pepeo; kongo crvena; adsorpcijske izoterme; kinetika; termodinamički parametri
• Keywords (english): sorption; fly ash; congo red; adsorption isotherms; adsorption kinetic; thermodinamics parameters
• Language: croatian
• URN:NBN: urn:nbn:hr:149:855829
• Study programme: Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra primijenjene kemije (magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-03-07 11:31:36