Data for: Catalytic wet peroxide oxidation of natural organic matter to enhance the treatment of surface waters at urban and rural drinking water plants

Published: 5 February 2021| Version 1 | DOI: 10.17632/rgrp7hjx6v.1


The efficiency of the CWPO process driven by an Al/Fe-PILC clay catalyst was evaluated in the removal of dissolved natural organic matter from different real water supplies: either raw or partially-treated water at several stages of drinking water urban plants (three points at three different UPs), or drinking water rural plants (five RPs) were processed at natural and varied conditions of pH, temperature, and environmental pressure. The optimal conditions of the CWPO reaction were refined taking into account the presence of well-known scavenging, inorganic anions in real surface water supplies. Besides, the catalyst preparation from technical-grade reagents was assessed. The catalytic results are analyzed in terms of DOC and total nitrogen mineralization, color removal (456 nm), the evolution of SUVA254, and efficiency of H2O2 consumption, but also taking into account the influence of the physicochemical properties displayed by the input natural water samples (pH, temperature, apparent color, UV254 absorbance, turbidity, alkalinity, and contents of main inorganic anions) on the catalytic performance using statistical tools. This dataset displays all the raw and treated data regarding the catalytic wet peroxide oxidation of dissolved Natural Organic Matter (NOM) in all, a synthetic surrogate of NOM, and several real surface water samples collected at urban and rural drinking water treatment plants (DWTPs). The catalytic reactions were performed in the presence of Al/Fe-PILC clay catalysts. The data here shown consists of: 1. Physicochemical properties of the Al/Fe-PILC clay catalysts used. 2. Identification of the real surface water samples studied. 3. Average standard deviations for all catalytic responses as a function of the type of water and DWTP, as the quality control of the catalytic data. 4. Characteristics of the statistical optimization of the CWPO degradation of NOM and the experimental data obtained (Factors, levels, covariates). 5. Multiple regression analysis measuring the correlation of the physicochemical properties of the input real water samples over every catalytic response. 6. Final average DOC values for the effluents of every stage of treatment at DWTPs and the CWPO treatment. 7. Current stages of treatment at the urban conventional DWTPs. 8. Composition of the synthetic surrogate of dissolved NOM employed for the statistical optimization of the CWPO catalytic degradation. 9. Estimated response surface plots for every catalytic response and Desirability-based multiresponse surface which allowed establishing the optimal reaction conditions. 10. Measured color removal in urban and rural plants through CWPO treatment. 11. Measured consumption of hydrogen peroxide at urban and rural plants through CWPO treatment. 12. Measured nitrogen removal through CWPO treatment. 13. pHpzc of the Al/Fe-PILC clay catalyst.


Steps to reproduce

1. Two Al/Fe-pillared clay catalysts were prepared from highly concentrated precursors at 1.5 kg bench-scale and the main physicochemical properties determined by X-ray Fluorescence (XRF), X-Ray diffraction patterns (XRD) recorded over 60-mesh powdered samples. The cationic exchange capacity (CEC) of the pillared materials (Al/Fe-PILC) was determined by micro-Kjeldahl analysis [Galeano et al., 2010], and the textural analyses were conducted from the nitrogen adsorption-desorption isotherms at 77 K. 2. Synthetic water was prepared according to the method reported in advance [García-Mora et al., 2021] in order to closely resemble the planned DOC concentrations required in each CWPO catalytic test. 3. Real samples from urban (U) drinking water treatment plants and rural (R) aqueducts were sampled to perform the CWPO experiments. 4. CWPO catalytic experiments were made at natural conditions of pH and T of real water samples (as collected). 5. Color removal of the CWPO treated samples was determined by spectrophotometric method in a UV 2600 Shimadzu spectrophotometer according to method elsewhere reported [García-Mora et al., 2021; Gómez-Obando et al., 2019]. 6. H2O2 free concentration through the CWPO experiments was determined by the iodometric method according to method reported in [García-Mora et al., 2021; Gómez-Obando et al., 2019]. 7. Nitrogen removal in the CWPO catalytic test was determined from the dissolved nitrogen converted to NO in a catalytic furnace set to 720 °C and then dragged to a chemiluminescence detector (mg N/L) [Gómez-Obando et al., 2019]. 8. The pH of the point of zero charge (pHpzc) of the Al/Fe-PILCtechnical clay catalyst was measured by a batch equilibration technique using the procedure reported by Čerović et al., 2002. 9. The statistical optimization of the CWPO degradation of NOM was carried from a rotatable-orthogonal 2^2 factorial design of experiments (16 trials). Experimental factors: (i) dose of hydrogen peroxide (mg H2O2/mg DOC) and (ii) catalyst concentration (g/dm^3); pH, temperature, and input concentration of DOC (mg C/dm^3) were all handled as non-controllable parameters in actual drinking water treatment plants [García-Mora et al., 2021]. 10. The statistical analysis of the data was made by the Response Surface Methodology (RSM) using the Statgraphics Software Package (Centurion XVI, version 16.1.03); the multiple-response optimization of the experimental factors was performed by raising a Desirability function. 11. A bivariate correlation was raised as exploratory analysis to find out a possible correlation between the three main responses and input physicochemical properties: pH, T, true color, UV254, DOC, DN, SUVA254, turbidity, alkalinity, Cl^-, (PO4)^3-, (NO3)^-, (SO4)^2-, and dissolved iron. The fitting was made by multiple regression analysis. The p-value < 0.05 was used to determine the statistical significance.


Universidad de Antioquia, Universidad de Narino


Surface Water, Dissolved Organic Matter, Natural Organic Matter, Pillared Clay, Drinking Water Treatment, Oxidation Catalysis, Clays Catalyst