Sustainable Bio-Based Phenol-Formaldehyde Resoles Using Hydrolytically Depolymerized Kraft Lignin.

In this study bio-based bio-phenol-formaldehyde (BPF) resoles were prepared using hydrolytically depolymerized Kraft lignin (DKL) as bio-phenol to partially substitute phenol. The effects of phenol substitution ratio, weight-average molecular weight () of DKL and formaldehyde-to-phenol (F/P) ratio were also investigated to find the optimum curing temperature for BPF resoles. The results indicated that DKL with ~ 1200 g/mol provides a curing temperature of less than 180 °C for any substitution level, provided that F/P ratios are controlled.

Detailed modeling of oxalic acid degradation by UV-TiO nanoparticles: Importance of light scattering and photoreactor scale-up.

A detailed computational fluid dynamics model is presented that integrates reactor hydrodynamics with advanced light models and UV-TiO advanced oxidation kinetics to yield the degradation of oxalic acid in a dispersed-phase photoreactor. Model predictions were first compared against experimental data obtained from the literature and subsequently used in a parametric study for investigating scale-up effects associated with both process and photoreactor variables. Investigated variables included: TiO concentration (5-400 mg L), initial oxalic acid concentration (0.

Solar degradation of diclofenac using Eosin-Y-activated TiO: cost estimation, process optimization and parameter interaction study.

Diclofenac (DCF), a widely used non-steroidal anti-inflammatory drug, is a commonly detected substance that readily accumulates in tissues of aquatic fish and poses a threat to wildlife and freshwater quality. Advanced Oxidation Processes have been employed as an alternative due to the inadequacy of conventional treatment methods of trace contaminants. This study utilized an innovative method of solar-activation of TiO using Eosin-Y dye for the degradation of DCF.

Nanoparticle scattering characterization and mechanistic modelling of UV-TiO2 photocatalytic reactors using computational fluid dynamics.

A computational fluid dynamic (CFD) model was developed to describe the process performance of a semi-batch annular TiO2-UV photoreactor in an Eulerian framework. The model accounted for the optical behaviour of titanium dioxide (TiO2) suspensions, the flow distribution and the oxalic acid degradation in the reactor. The scattering component of the optical model, explicitly included in the CFD simulations using a TiO2-specific scattering phase function integrated in the radiative transfer equation, was calibrated using an optical goniometer by comparing simulated scattering light profiles against irradiance measurements collected for various TiO2 concentrations and UV wavelengths and subsequently solved by the discrete ordinate (DO) radiation model.

Nondeterministic computational fluid dynamics modeling of Escherichia coli inactivation by peracetic acid in municipal wastewater contact tanks.

Wastewater disinfection processes are typically designed according to heuristics derived from batch experiments in which the interaction among wastewater quality, reactor hydraulics, and inactivation kinetics is often neglected. In this paper, a computational fluid dynamics (CFD) study was conducted in a nondeterministic (ND) modeling framework to predict the Escherichia coli inactivation by peracetic acid (PAA) in municipal contact tanks fed by secondary settled wastewater effluent. The extent and variability associated with the observed inactivation kinetics were both satisfactorily predicted by the stochastic inactivation model at a 95% confidence level.