Publications by authors named "Chiung-Fen Chang"

As an environmentally friendly and energy-efficient technology, photocatalysis holds considerable potential for eliminating organic pollutants. In this study, novel visible-light-driven AgPO-decorated nitrogen-doped TiO nanotubes (AgPO/N-TNTs) photocatalysts with advanced properties of heterostructures were successfully synthesized and used to degrade methylene blue (MB) dye. The fabrication of AgPO/N-TNTs photocatalysts involved a two-step electrochemical anodization to obtain TiO nanotubes (TNTs) and the wet impregnation of the amorphous tubular structure in NH solution, followed by calcination in air to obtain crystallized nitrogen-doped TiO nanotubes (N-TNTs).

View Article and Find Full Text PDF

Hydroquinone (HQ) is one of the major deleterious metabolites of benzene in the human body, which has been implicated to cause various human diseases. In order to fabricate a feasible sensor for the accurate detection of HQ, we attempted to electrochemically modify a piece of common 2B pencil lead (PL) with the conductive poly(3,4-ethylenedioxythiophene) or PEDOT film to construct a PEDOT/PL electrode. We then examined the performance of PEDOT/PL in the detection of hydroquinone with different voltammetry methods.

View Article and Find Full Text PDF

Electrochemical advanced oxidation processes (EAOPs) regarded as a green technology for aqueous ibuprofen treatment was investigated in this study. Multi-walled carbon nanotubes (MWCNTs), Pt nanoparticles (Pt NPs), and PtRu alloy, of which physicochemical properties were characterized by XRD and X-ray absorption spectroscopy, were used to synthesize three types of cheap and effective anodes based on commercial conductive glass. Furthermore, the operating parameters, such as the current densities, initial concentrations, and solution pH were also investigated.

View Article and Find Full Text PDF

Metal accumulation in sediments threatens adjacent ecosystems due to the potential of metal mobilization and the subsequent uptake into food webs. Here, contents of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) and trace elements (Ga, In, Mo, and Se) were determined for river waters and bed sediments that received sewage discharged from traditional and semiconductor industries. We used principal component analysis (PCA) to determine the metal distribution in relation to environmental factors such as pH, EC, and organic matter (OM) contents in the river basin.

View Article and Find Full Text PDF

Magnetic polyvinyl alcohol adsorbent M-PVAL was employed to remove and concentrate dimethyl phthalate DMP. The M-PVAL was prepared after sequential syntheses of magnetic Fe3O4 (M) and polyvinyl acetate (M-PVAC). The saturated magnetizations of M, M-PVAC, and M-PVAL are 57.

View Article and Find Full Text PDF

Dimethyl phthalate (DMP) was treated via wet oxygen oxidation process (WOP). The decomposition efficiency η DMP of DMP and mineralization efficiency η TOC of total organic carbons were measured to evaluate the effects of operation parameters on the performance of WOP. The results revealed that reaction temperature T is the most affecting factor, with a higher T offering higher η DMP and η TOC as expected.

View Article and Find Full Text PDF

This study investigated applications of the electrochemical anodic oxidation process with Pt-FTO and Pt/MWCNTs-FTO glasses as anodes on the treatment of one of the most important emerging contaminants, naproxen. The anodes used in this study have been synthesized using commercial FTO, MWCNTs and Pt nanoparticles (PtNP). XRD patterns of Pt nanoparticles coated on FTO and MWCNTs revealed that MWCNTs can prevent the surface of PtNPs from sintering and thus provide a greater reaction sites density to interact with naproxen, which have also been confirmed by higher degradation and mineralization efficiencies in the Pt/MWCNTs-FTO system.

View Article and Find Full Text PDF

Magnetic TiO2 (MT) composites were prepared and applied to degrading phenol, which is one of the listed priority pollutants. The effects of heat treatment under preparation on the photocatalytic activity of MT composites have been investigated by varying the soaking time under a constant final temperature of 823 K. The total organic carbon and ring-remaining intermediates of o-DHB, p-DHB and 1,4-BQ in solution were detected during the photodegradation of phenol.

View Article and Find Full Text PDF

High gravity rotating packed bed (HGRPB) reactor possesses the property of high mass transfer rate, which is expected to promote the adsorption rate for the process. In this study, HGRPB has been applied on adsorption removal of methomyl from solution, adopting the adsorbent of activated carbon F400. The influence of operating parameters of HGRPB on mass transfer such as the rotating speed (N(R)), the flow rate of solution (F(L)) and initial concentration of methomyl (C(b0)) were examined.

View Article and Find Full Text PDF

This study examined the desorption of copper ions, which were adsorbed on the magnetic polymer adsorbent (MPA) of polyvinyl acetate-iminodiacetic acid (M-PVAC-IDA), by ethylenediaminetetraacetic acid (EDTA). Stage-wise desorptions were applied to remove the Cu(II) ions from the Cu(II) adsorbed M-PVAC-IDA (A-M-PVAC-IDA). About seven desorption runs were needed to regenerate the A-M-PVAC-IDA.

View Article and Find Full Text PDF

In this study, a high-gravity rotating packed bed (HGRPB or HG) was used as a catalytic ozonation (Cat-OZ) reactor to decompose phenol. The operation of HGRPB system was carried out in a semi-batch apparatus which combines two major parts, namely the rotating packed bed (RPB) and photo-reactor (PR). The high rotating speed of RPB can give a high volumetric gas-liquid mass transfer coefficient with one or two orders of magnitude higher than those in the conventional packed beds.

View Article and Find Full Text PDF

The radio frequency plasma pyrolysis technology, which can overcome the disadvantages of common pyrolysis methods such as less gas products while significant tar formation, was used for pyrolyzing the biomass waste of rice straw. The experiments were performed at various plateau temperatures of 740, 813, 843 and 880K with corresponding loading powers of 357, 482, 574 and 664W, respectively. The corresponding yields of gas products (excluding nitrogen) from rice straw are 30.

View Article and Find Full Text PDF

In this study, a high-gravity rotating packed bed (HGRPB) was used as a catalytic ozonation reactor to decompose dimethyl phthalate (DMP), an endocrine disrupting chemical commonly encountered. The HGRPB is an effective gas-liquid mixing equipment which can enhance the ozone mass transfer coefficient. Platinum-containing catalyst (Pt/-Al2O3) of Dash 220N and ultra violet (UV) lamp were combined in the high-gravity ozonation (HG-OZ) system to enhance the self-decomposition of molecular ozone in liquid to form highly reactive radical species.

View Article and Find Full Text PDF

The hypercrosslinked polymers Macronet MN-150 and MN-500 (denoted as MN-150 and MN-500) were investigated to remove the pesticide methomyl from aqueous solutions via adsorption. Furthermore, the effect of humid acid (used as background organic compound) on the adsorption capacity of methomyl for MN-150 was examined. The equilibria and kinetics of the adsorption of methomyl onto MN-150 and MN-500 can be well correlated with Langmuir and Freundlich isotherms, and conventional kinetic models (e.

View Article and Find Full Text PDF

Basic oxygen furnace slag (BOF slag) is a solid waste arisen from the steel making process. FeO is one of the major components of BOF slag. The FeO-containing property of BOF slag makes it possible to catalyze the Fenton reaction.

View Article and Find Full Text PDF

Polynuclear aromatic hydrocarbons (PAHs), which are environmental hormones and carcinogens, are viewed as the priority pollutants to deal with by many countries. Most PAHs are hydrophobic with high boiling and melting points and high electrochemical stability, but with low water solubility. Compared with other PAH species, naphthalene has less toxicity and is easily found in the environment.

View Article and Find Full Text PDF

2-Mercaptothiazoline (2-MT) is widely used as an organic corrosive as well as a diffusion inhibitor due to its high ability to form metal-chelate Schiff base complexes. This study investigated the elimination of 2-MT from aqueous systems with adsorption process to reach the goal of sustainable use of water resources. The Freundlich and Langmuir adsorption isotherms were adopted to examine the adsorption behavior of two types of 2-MT (i.

View Article and Find Full Text PDF