Degradation Of Isopropyl Alcohol Research Articles

Green and efficient preparation and application of weakly crystalline TiO2 with high catalytic activity

Weakly crystalline TiO2 with high catalytic activity was prepared using a simple green chemical oxidation reaction at low temperatures, achieving 90% degradation of methylene blue (MB) at 20 min and 100% degradation of isopropyl alcohol (IPA) at 2 h.

Degradation of isopropyl alcohol using UV and persulfate in a large reactor

This investigation concerns the degradation of isopropyl alcohol (IPA) in aqueous solutions using UV and persulfate (PS) in a large reactor, as well as the effects of PS concentration, initial IPA concentration, pH, and added anions on this process. A higher PS concentration was associated with more efficient degradation of IPA. However, an excessive PS concentration limited the degradation of IPA. Moreover, the efficiency of degradation of IPA increased with decreasing initial IPA concentration. SO4− was identified by performing quenching studies using specific alcohols. The results thus obtained reveal that SO4− was the predominant radical in the UV/PS process at pH 7. The degradation of IPA by the UV/PS process in a large reactor exhibited pseudo-first-order kinetics. The efficiency of degradation of IPA followed the order pH 7 > pH 4 > pH 10. Anions (Cl−, CO32–, and HCO3–) inhibited the degradation of IPA and their inhibitive effects followed the order Cl− > CO32– > HCO3–. At pH 7, a PS concentration of 2.10 g/L, and an initial IPA concentration of 100 mg/L, 100% of IPA was degraded in the absence of anions with an observed degradation rate constant of 0.1890 min−1, as measured after 20 min. Comparison with the heat/PS process demonstrates that the degradation of IPA was improved by the UV/PS process at a low temperature. Accordingly, the proposed method that is based on the UV/PS process is an effective method for degrading IPA in aqueous solutions.

Growth Kinetics of Acclimated Mixed Culture for Degradation of Isopropyl Alcohol (IPA)

Iso-propyl alcohol (IPA) is an organic chemical regarded as a potential pollutant. The permissible exposure limit (PEL) of IPA specified by Occupational Safety and Health Administration (OSHA) is 400 mg L-1. In this study the aerobic biodegradation of IPA is carried out by an acclimated mixed culture obtained by sewage treatment plant, for the range of 200-700 mg L-1 of initial IPA concentration. The batch degradation study demonstrated that the maximum growth rate obtainable is 0.337 h-1. To explain the inhibition effects, different kinetic growth models such as Haldane, Luong and Edward models are applied. The experimental data are found to fit well with inhibition models having the values of coefficient of determination (R2) of 0.989, 0.986 and 0.984 respectively for Haldane, Luong and Edward models. Based on the disappearance of IPA, degradation is modeled by the three-half-order kinetics and the resulting kinetic parameters are reported.

Kinetics and Modeling of IPA Oxidation Using Ozone-Based Advanced Oxidation Processes

In this study, an oxidation model incorporating the mass transfer and kinetics approach based upon the rate constants for the reactions with ozone and ·OH radicals was developed to predict the degradation of isopropyl alcohol (IPA) and formation of its main byproduct, acetone. The self-decomposition of ozone in buffered water at pH 3 and 7 occurred via a first-order reaction. The ozone mass transfer coefficients are considerably higher at pH 7 than pH 3 due to the participation in the chemical reaction toward the hydroxyl ion. The oxidation model considering side reactions between ozone or ·OH radicals and byproducts has been established using nonlinear simultaneous differential equations. The reaction coefficients for IPA degradation are 0.008, 0.0236, 1.4931, and 1.4909 s-1 at pH 3 and 7 in O3 and O3/UV processes, respectively. The larger reaction coefficient found in the ozone/UV system indicates several competing mechanisms for hydroxyl radicals.

The oxidation study of 2-propanol using ozone-based advanced oxidation processes

In the present study, advanced oxidation processes (AOPs) have been successfully used to decompose isopropyl alcohol (IPA). IPA degradation and its major degradation intermediate, acetone formation and total organic carbon (TOC) removal efficiency were studied using O 3, O 3/UV, H 2O 2/UV, H 2O 2/O 3, and H 2O 2/O 3/UV processes at various physico-chemical conditions. Complete degradation of IPA was noted in AOPs whereas complete acetone decomposition was not observed under the experimental conditions. Ozonation process was strongly enhanced in the presence of UV light, H 2O 2 or in the presence of both oxidants. Ozonation process in the presence of UV light enhancement about 11%, 15%, 28% of IPA decomposition and 20%, 23%, 0% of TOC removal was observed at pH 3, 7, and 10. Similarly, in the presence of H 2O 2 (0.25 g/g) further enhancement of 31%, 50%, 18% of IPA degradation and 26%, 30%, 27% of TOC removal at 180 min was noted at pH 3, 7, and 10, respectively. UV/H 2O 2 process was found to be the least efficient and UV/H 2O 2/O 3 was the most efficient process compared to all other selected AOPs. Acetone was identified as a primary degradation intermediate and subsequently acetic acid, formic acid, and oxalic acid were identified as secondary intermediates. It was concluded that ozone-based AOPs were efficient for IPA degradation in wastewater.

Visible light-sensitized photocatalyst immobilized on beads by CVD in a fluidizing bed

Abstract In this work, chemical vapor deposition in a fluidized bed was employed for the immobilization of a photocatalyst on beads. By introducing carbon (TiOC), nitrogen (TiON) and iron (Fe/TiO 2 ) into TiO 2 matrix, samples were prepared, respectively. The X-ray diffractometer pattern of TiOC revealed a mixture of the anatase and rutile crystalline forms (65% and 34%, respectively) at the reaction temperature of 600 °C. TiOC absorbed in the visible region and showed photocatalytic activity in terms of isopropyl alcohol (IPA) degradation under a fluorescent lamp and blue light-emitting diode. TiON exhibited a shoulder in the absorption near 520 nm and was photocatalytically active under visible light at 460 nm. In the case of the Fe/TiO 2 species, lowering the bubbler temperature, i.e. reducing the amount of doped-iron, caused the rate of CO 2 evolution to increase during IPA degradation. Among studied species, Fe/TiO 2 under the condition of the bubbler temperature at 109 °C with a flow rate of 10 cm 3 /min showed highest photocatalytic activity in IPA degradation.