Naslov
Influence of ultrasound amplitude on borax nucleation kinetics in a batch crystallizer at different cooling rates

Autori
Ćosić, Marija ; Čelan, Antonija ; Ramljak, Mia ; Kuzmanić, Nenad

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
28th Croatian Meeting of Chemists and Chemical Engineers, Rovinj, Croatia, 2023 / Hranjec, Marijana - Zagreb : Hrvatsko društvo kemijskih inženjera i tehnologa (HDKI), 2023, 148-148

Skup
28th Croatian Meeting of Chemists and Chemical Engineers

Mjesto i datum
Rovinj, Hrvatska, 28.03.2023. - 31.03.2023

Vrsta sudjelovanja
Poster

Vrsta recenzije
Domaća recenzija

Ključne riječi
sonokristalizacija, boraks, kinetika nukleacije, ultrazvučna amplituda, brzina hlađenja, miješanje
(sonocrystallization, borax, nucleation kinetics, ultrasound amplitude, cooling rate, mixing)

Sažetak
The ultrasound irradiation during crystallization (i.e. sonocrystallization) is increasingly used due to the numerous advantages that this operation provides. However, for process design and control it is of enormous importance to define the influence of process conditions on nucleation kinetics of particular substance. In this work the influence of ultrasound amplitude on nucleation kinetics of borax decahydrate were systematically investigated in laboratory scale stirred crystallizer of 2, 7 dm3. The tests were performed at four amplitudes of ultrasonic power, A, in the range of 0 to 30 %, and at four cooling rates, b, from 4 to 10 °C h-1 measuring the metastable zone width and power consumption. The experimental results showed narrowing of the metastable zone width by increasing ultrasound amplitude and decreasing cooling rate. Finally, the functional dependence of the metastable zone width on these variables was derived (∆Tmax = K A-0.739 b0.3525). It was found that in all systems the value of the apparent order of nucleation is the same, while the nucleation rate constant increases with the ultrasound amplitude, i.e. with the power dissipated to the system. It was also found that the nucleation started by the primary nucleation mechanism at all examined conditions, while its rate is considerably affected by the ultrasound amplitude and the cooling rate. Nevertheless, granulometric properties of crystals obtained at 20 % amplitude show close values of mean volume diameter and its standard deviation regardless of the cooling rate. In addition, these values are significantly lower than those obtained in the silent system at 0 % amplitude.

Izvorni jezik
Engleski

Znanstvena područja
Kemijsko inženjerstvo

POVEZANOST RADA