Modeling mechanism of oscillating catalytic processes, with application to hydrogenperoxide decomposition

Urađena je detaljna analiza postupaka koje bi trebalo primeniti pri analizi svih složenih procesa, a posebno pri modeliranju oscilatornih katalitičkih reakcija. Sintezom odabranih metoda sačinjen je sopstveni opšti postupak koji je primenjen na polazni model reakcije Braj- Libhavski. Tokom postupka modeliranja, formiran je niz redukovanih modela i utvrđene su njihove osobine. Dobijeni uprošćeni modeli i dalje omogućavaju simulaciju oscilacija, a dovoljno su pojednostavljeni da omoguće i kvantitativnu analizu uslova stabilnosti. Primenjena analitička procedura daje uvid u ulogu pojedinih delova reakcionog mehanizma u celokupnom procesu i naročito u mehanizmu oscilovanja.Detailed analysis was performed of the methods that should be employed in the analysis of complex processes, especially in the modeling of the oscillatory catalytic reactions. By synthesis of selected methods, our own general procedure was made and applied to the initial model of the Bray – Liebhavsky reaction. During the modeling process, a series of reduced models was created and their characteristics defined. The resulting simplified models still allow the simulation of oscillations, but they are sufficiently simplified to allow quantitative analysis of the stability conditions. Applied analytical procedure provides insight into the role of individual components of the reaction mechanism in the whole process and especially in the mechanism of oscillations

Kinetics of the Bray-Liebhafsky oscillatory reaction perturbed by polymer supported cobalt catalyst

The Bray-Liebhafsky (BL) oscillatory reaction generated in the batch reactor at 62- 68 oC was perturbed by cobalt(II)-nitrate, supported on the macroreticular copolymer of poly-4-vinylpyridine with divinylbenzene (Co-PVPDVB). The kinetic data was analyzed of the complex pathways of the hydrogen peroxide decomposition in the examined BL reaction. The obtained results confirm that the kinetics of the BL reaction in the presence Co-PVPDVB comes partially from the Co-catalyst and partially from the macroreticular copolymer support.Oscilatorna reakcija Bray-Liebhafsky (BL) realizovana u zatvorenom reaktoru na temperaturi 62-68 oC je perturbovana sa kobalt(II)nitratom ugrađenim na makroretikularnom kopolimeru poli-4-vinilpiridina sa divinilbenzenom (Co- PVPDVB). Analizirani su kinetički podaci kompleksnih reakcionih puteva razlaganja vodonikperoksida u ispitivanoj BL reakciji. Dobijeni rezultati potvrđuju da je u prisustvu Co-PVPDVB kinetika BL reakcije delimično određena Co-katalizatorom, a delimično makromolekularnim kopolimernim nosačem katalizatora

Activity of polymer supported cobalt catalyst in the Bray-Liebhafsky oscillator

The infuence of poly-4-vinylpyridine-co-divinylbenzene-Co2+ catalyst on the Bray-Liebhafsky (BL) oscillator used as the matrix for establishing catalyst's activity was analyzed. The addition of the catalyst do not change the dynamics of the reaction in the BL matrix, but the periods of the oscillatory evolution as well as the preoscillatory period (tau(1)) and the duration from the beginning of the reaction to the end of the oscillatory state (tau(end)). All experimental results are simulated satisfactory

Regularity of Intermittent Bursts in Briggs Symbol of the Klingon Empire Rauscher Oscillating Systems with Phenol

The intermittency or intermittent bursting as the type of dynamic state when two qualitatively different behaviors replace one another randomly during the course of the reaction, although all the control parameters remain constant, is found in the Briggs Symbol of the Klingon Empire Rauscher oscillating system moderated by a very small amount of phenol. Within a range of phenol concentrations, the oscillation amplitude is diminished considerably, and after oscillations cease, they repeat intermittently, giving several bursts of oscillations. For the concentrations used here, the range of phenol concentrations where intermittent bursting oscillations occur in a closed reactor is ca. 1.8x10(-5) to 3.6x10(-5) M. Bursting also occurs in an open reactor and can be sustained indefinitely at 5.53x10(-5) M concentration. The intermittent bursting behavior is robust, and can be achieved at a variety of conditions