Homogeneous and heterogeneous AOPs for rapid degradation of Triton X-100 in aqueous media via UV light, nano titania hydrogen peroxide and potassium persulfate

Abstract

a b s t r a c t Feasibility of degradation of Triton X-100 as a widely used and resistive surfactant in aqueous media was studied via some homogeneous and heterogeneous AOPs of UV/TiO 2 , UV/H 2 O 2 and UV/S 2 O 8 2− . For treatment of solutions containing 20 mg/L of Triton, the optimum obtained conditions are: 5.0 mg/L of nano TiO 2 , 270.3 mg/L of KPS, and 34.0 mg/L of H 2 O 2 (1 mM of the oxidants), initial natural pH of 5.4 and temperature of 45 • C. Under these conditions, the degradation efficiency for the UV/TiO 2 , UV/H 2 O 2 and UV/S 2 O 8 2−processes exceeds 71.9% (in 60 min), 80.9% (in 60 min) and 98.5% (in only 30 min) respectively. It was found that simultaneous application of these heterogeneous and homogeneous AOPs (UV/TiO 2 /H 2 O 2 or S 2 O 8 2− ) is not desirable due to some physico-chemical retarding effects. The influence of temperature on the reactions was examined in the range of 15-45 • C and a kinetic power law model jointed with the Arrhenius equation was introduced. A pseudo first order reaction rate is appropriate for UV/S 2 O 8 2− and UV/TiO 2 processes under optimum conditions, while this order for UV/H 2 O 2 process is 2.27. Meanwhile, the initial rates of degradation in UV/TiO 2 process can be described well by the Langmuir-Hinshelwood kinetic model. Analysis of energy consumptions (thermal and electrical) revealed that increasing in temperature is an effective factor for lowering the energy cost of the preferred process of UV/S 2 O 8 2− .

Pressurized photo-reactor for the degradation of the scarcely biodegradable DPC cationic surfactant in water

“…An enhancement of the degradation performance was observed passing from 0.50 mM to 0.17 mM. Under photocatalysis the surfactant mineralization decreases with increasing the initial concentration of the pollutant, as expected from a Langmuir-Hinshelwood type behavior, typical of photocatalytic processes [26,27]. A similar trend can also be observed in the photolytic runs: in these cases the same amount of photons reacts with an higher number of DPC molecules by changing from 0.17 to 0.50 mM.…”

Recent advances and prospects of catalytic advanced oxidation process in treating textile effluents

“…UV irradiation can be used as a single technique or in combination with other AOPs to offer both ecological and economic advantages. The combination of UV with other AOPs such as homogeneous and heterogeneous Fenton-based processes, catalytic ozonation, electrochemical oxidation, sonolysis, H 2 O 2 , and heterogeneous photocatalytic oxidation produces a highly effective result, which could not be achieved if they are used separately (Saien et al 2011, Saekow et al 2012.…”

An effective heterogeneous iron-based catalyst to activate peroxymonosulfate for organic contaminants removal

“…In recent years, advanced oxidation processes (AOPs) have received considerable and increasing attention as promising technologies to treat wastewater containing toxic and non-biodegradable pollutants due to the generation of highly reactive radicals [1- 6]. Among these various AOPs, activated peroxymonosulfate (PMS) oxidation has been regarded as an interesting treatment method because PMS is more easily activated compared with hydrogen peroxide, which is one of the most commonly used oxidants in AOPs [7,8].…”