Sonophotolytic degradation of synthetic pharmaceutical wastewater: Statistical experimental design and modeling

Sonochemical techniques to degrade pharmaceutical organic pollutants

“…This result is expected because by increasing the magnitude of power dissipation of the horn, there will be an increase in the number of cavities generated, and hence, the cumulative pressure pulse (number of cavities multiplied by the collapse pressure due to a single cavity) will also increase. After investigating the sonophotolytic degradation of synthetic pharmaceutical wastewater (composition of 4-aminophenol, paracetamol, phenol, chloramphenicol, benzoic acid, salicylic acid, diclofenac sodium, and nitrobenzene), Ghafoori et al (2015) have found that by increasing the ultrasound power, higher TOC percent removal was achieved. The TOC removal was 60.22 % at 20 W compared to 75.26 % with power of 140 W. The elevated ultrasound power causes the Environ Chem Lett higher rate of the breakage of H 2 O 2 molecules in aqueous solution; consequently, the concentration of hydroxyl radicals was increased, and the produced radicals attack the organic matters.…”

“…The TOC removal was 60.22 % at 20 W compared to 75.26 % with power of 140 W. The elevated ultrasound power causes the Environ Chem Lett higher rate of the breakage of H 2 O 2 molecules in aqueous solution; consequently, the concentration of hydroxyl radicals was increased, and the produced radicals attack the organic matters. Furthermore, an increase in the ultrasonic power contributed to enhance mixing intensity due to the turbulence and microstreaming which is generated during the cavitational microbubble collapse (Ghafoori et al 2015). Other authors have pointed out that lower intensities are more effective than higher intensities at the same total power, not only in experiments on water sonolysis but also in the degradation of organic compounds.…”

“…An important synergistic effect between sonolysis and photoFenton (UV/H 2 O 2 /Fe) of 45.4 % was quantified using the first-order rate constants for TOC (Duran et al 2013). Ghafoori et al (2015) have investigated the use of ultrasound to enhance degradation of synthetic pharmaceutical wastewater (a mixture of 4-aminophenol, paracetamol, phenol, chloramphenicol, benzoic acid, salicylic acid, diclofenac sodium, and nitrobenzene) by applying different processes including sonolysis (US alone), photolysis (UV alone), and combination of both UV and US. Total organic carbon (TOC) measurements were used to determine the effectiveness of oxidation process.…”

“…The lower in reported results could be explained by considering the nature of components being studied which is a multicomponent wastewater more complicated than that of single component. Also, the output power of the US instrument and the power of the UV light could be influential in the degradation efficiency (Ghafoori et al 2015). In another study, Naddeo et al (2009) reported a method for the removal of diclofenac in aqueous solutions using ultrasound treatment with ozone addition.…”

Experimental statistic design applied for obtaining Zn:xCe by microwave-assisted hydrothermal method with photocatalytic property

“…However, microwave-assisted hydrothermal (MAH) method is more advantageous because of its easy operation, low cost, lower temperature, and greater control of morphology [9]. This is the method used in this study along with the statistical design in order to optimize the process of synthesis.…”