Implementation of a venturi photocatalytic reactor: Optimization of photodecolorization of an industrial azo dye

Abstract

The photocatalytic decolorization of the textile azo dye C.I. Basic Red 46 was studied in a semi-pilot photocatalytic reactor combined with an emulsion venturi. The venturi has two principal roles, bring dissolved oxygen necessary for the photocatalytic reaction, and ensure a good homogenization, within its divergent, of the mixture dye solution-air-TiO 2 particles. This study shows that this proposed photoreactor can be easily applied and extrapolated in photocatalysis reactions with a significant performance.The optimization of UV/TiO 2 process in the photoreactor was carried out using the response surface methodology (RSM), based on the central composite design (CCD), to assess individual and interactive effects of the four main independent parameters (initial dye concentration, concentration of TiO 2 , flow rate (Q L ) and initial (pH) on the decolorization Efficiency Y (%) of (BR46)). Experimental results found from RSM was in good agreement with the model prediction (R 2 = 0.96 and Adj-R 2 = 0.92) and the presence of venturi has increased the discoloration rate of 20%. The optimization results showed that maximum decolorization efficiency was achieved at the optimum conditions: pH 8.68, TiO 2 = 0.97 g/L, Q L 1324 L h À1 , [RB46] 5 mg L À1 . ª 2015 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Waste valorization as low-cost media engineering for auxin production from the newly isolated Streptomyces rubrogriseus AW22: Model development

“…These graphics help understand and describe the two variables' combined effect on IAA production by AW 22. According to the contour plot forms, it is possible to instantly verify the significance of the interaction, which may be high if the contour plot is elliptical and saddle or, on the contrary, low if it represents a circular shape (Berkani et al, 2019). At the same time, the remaining pair of factors were kept at their centre point, thus efficiently determining the maximum response value under the influence of the operating inputs.…”