Evaluation of the lead and chromium removal capabilities of Bacillus subtilis-induced food waste compost-based biomedia.

Food waste compost (FWC) is a sustainable recycling approach employed in soil media, offering extensive advantages to urban areas by promoting resource circulation and effectively managing water pollution. To improve value, Bacillus subtilis (B. subtilis)-induced FWC-based biomedia (BIBM) was produced via a secondary treatment involving selective meso-thermophilic stages.

Modelling heavy-metal phytoextraction capacities of Helianthus annuus L. and Brassica napus L.

Greenhouse experiments were conducted to test the phytoextraction potential of sunflower (Helianthus annuus L.) and rape (Brassica napus L.) during the initial growth in the heavy metal (i.

Physicochemical and fertility characteristics of microalgal soil ameliorants using harvested cyanobacterial microalgal sludge from a freshwater ecosystem, Republic of Korea.

The recovery and reuse strategy of cyanobacterial microalgal sludge (CyanoMS) is a novel sustainable platform that can mitigate cyanobacterial harmful algal blooms (CyanoHABs) in the freshwater system. This study aimed to assess the nutritional feasibility of harvested CyanoMS for microalgal soil ameliorants (MSAs) as efficient biofertilizers by the composting process. Most MSAs exhibited stable nutrient levels during the sequential metabolic phases for the entire period.

Application of WQI and TSI for comprehensive water quality assessment immediately after the construction of the Yeongju Multipurpose Dam in the Naeseong Stream Basin, Republic of Korea.

This study evaluated changes in the aquatic environment and river water quality due to the construction of the Yeongju Multipurpose Dam (YMD) in the Naeseong Stream Basin, Republic of Korea, over eight years. This study evaluated water quality characteristics immediately after dam construction in the target area with aquatic environmental values and important water quality parameters using classification schemes. The drastic formation of new lentic systems in the upstream dammed pool presented exponential algal growth and high potential availability of nitrogenous compounds depending on seasonally.

Evaluation of Titanium Tetrachloride (TiCl₄) as an Alternative Coagulant and Characterization of Recovered TiO₂.

Titanium tetrachloride (TiCl₄) as an alternative coagulant to remove organic matters and nutrients from the effluent of the secondary wastewater treatment was evaluated by comparison of removal efficiency of total phosphorous to Al- and Fe-based coagulants. Also, the surface characteristics, elemental contents, and crystallinity of the TiO₂ produced from wastewater sludge flocculated with TiCl₄ coagulant were investigated depending on the calcination temperatures. The more dosages of coagulants were injected, the greater concentrations of the cations (Al, Fe, Ti) and hydrogen ions (H) resulted in the lower pH.

Comparison of Immobilization Methods for TiO₂-Embedded Expanded Polystyrene Balls and Growth Inhibition of .

Two immobilization methods (i.e., ice water-soaked using a digital temperature controller vs.

Generation of Nano Bubbles Using Cavitation Technique and Monitoring of Strawberry Growth by the Generated Nano Bubbles.

In this study, nano bubbles (NBs) of around 100 nm size were generated by using GoodSam-NB generator (made by S company) which utilizes cavitation technique. The generated NBs were directly applied to the strawberry cultivation process to monitor the productivity of strawberry. When the aqueous nutrient solution with NBs was supplied to the strawberry culture medium, it had a slightly higher initial concentration of dissolved oxygen (DO) compared to the nutrient solution prepared with ordinary groundwater at a concentration of about 9 mg/L and did not decrease over time.

Evaluation of heavy metal phytotoxicity to Helianthus annuus L. using seedling vigor index-soil model.

A mathematical model to estimate seedling vigor index (SVI) of sunflower (Helianthus annuus L.) seeds in soils contaminated with heavy metals was developed. This model was used to quantitatively describe the complex effects of heavy metal concentrations in soils (C) on seed germination and seedling growth.

Electromagnetically-vibrated solid-phase microextraction for analysis of aqueous-miscible organic compound transport in soil columns.

Current methods of sampling pore water from soil columns to determine solute concentrations are slow and require relatively large volumes. Accordingly, an electromagnetically-vibrated (EMV) solid-phase microextraction (SPME) device was evaluated for determining temporal and spatial distributions of solute pore-water concentrations (solute concentration profiles) for four organic compounds, two polar (2-hexanone, 2,4-dimethyl phenol) and two nonpolar (toluene, 1,4-dichlorobenzene), in columns packed with simulated aquifer sands with different fractions of organic carbon. In batch equilibrium extraction tests, the equilibrium extraction time of the organic compounds in aqueous mixtures decreased from 30 to less than 10 min as the frequency of electromagnetic vibration increased from zero to 250 Hz.

Growth inhibition of harmful algae using TiO-embedded expanded polystyrene balls in the hypereutrophic stream.

TiO-embedded expanded polystyrene (TiOEPS) balls were produced in large quantities using continuous manufacturing plants and four processes (i.e., fixing-coating-freeze drying-air drying).

Growth Inhibition of Using TiO₂-Embedded Expanded Polystyrene Balls.

Mass production technique of nanoscale TiO₂ particle-embedded expanded polystyrene (EPS) balls with temperature-controlled melting method was developed, and the photocatalytic activity of TiO₂-embedded EPS (TiEPS) balls to suppress the excessive growth of Microcystis aeruginosa ( aeruginosa) cultured from both indoor and outdoor experiments was verified under ultraviolet and solar light irradiation, respectively. According to the experimental results, the growth inhibition of M. aeruginosa was evidently observed by applying TiEPS balls, and increased proportionally with the surface area coverage of TiEPS balls.

Degradation of Metaldehyde in Aqueous Solution by Nano-Sized Photocatalysts and Granular Activated Carbon.

Metaldehyde has been detected in drinking water system in relatively high concentration exceeding European water quality standard. In order to address this problem, the aim of this project was to treat metaldehyde aqueous solution by advanced oxidation processes (AOPs) and granular activated carbon (GAC) column. Ten novel materials were tested for degradation rates of metaldehyde under ultraviolet light irradiation (UVC).

Removal of Cesium in Water Using Novel Composites Synthesized Nano-Sized Prussian Blue with Carbonyl Iron.

Among the various radioactive materials, Cesium is a major source of radioactive contamination and known to be the most dangerous radioactive material, can cause enormous damage to the ecosystem environment when released into the environment. Prussian Blue (PB) has been used as an adsorbent to effectively remove cesium, however it has the problem of being difficult to separate in water. In this study, carbonyl iron (CI) which is known as ferromagnetic synthesized with precursor of PB (FeCl₃ and potassium ferricyanide) to solve the problem of PB particles.

Mathematical estimation of heavy metal accumulations in Helianthus annuus L. with a sigmoid heavy metal uptake model.

It is a core issue in the application of phytoremediation technology to describe and predict the movement of contaminants from soil to plants. For this purpose, a mathematical model to describe the heavy metal accumulations in the entire soil-sunflower biomass system was developed, and validated using a sigmoid function and bioaccumulation factor. Both pot and field experiments were performed using sunflowers and target heavy metals (i.

Application of Titanium Dioxide (TiO₂)-Embedded Buoyant Photocatalyst Balls Using Expanded Polystyrene.

A new immobilization technique of nanoscale TiO₂ powders to expanded polystryrene (EPS) balls with temperature-controlled melting method was validated for mass production, and the photocatalytic activity of TiO₂ powder-embedded EPS (TiEPS) balls using methylene blue (MB) solution with different concentrations under ultraviolet irradiation and under the natural solar light irradiation. Whereas MB molecules were weakly adsorbed onto the surface of both TiO₂ powders and supporting polymers without any specific interactions, the photocatalytic efficiency of TiEPS balls with UV ( =0.016~0.

Preparation of Nano Spinel Doped TiO₂ and Its Photocatalytic Activity Evaluation Under Visible Light Irradiation.

Nano MgFe-TiO₂ photocatalyst was prepared by mixing nanoscale spinel compounds such as magnesium ferrite (MgFe) and TiO₂. The cations produced by MgFe are affected by various influencing factors such as calcination temperature, precursor, and mass ratio of Mg and Fe. This study is to evaluate the photocatalytic efficiency of nano MgFe-doped TiO₂ under visible light according to the composition ratio of Mg, Fe and TiO₂.

Development of Titanium Dioxide (TiO₂)-Embedded Buoyant Photocatalyst Balls Using Expanded Polystyrene.

A new immobilization technique of nanoscale TiO₂ powders to expanded polystryrene (EPS) balls with temperature-controlled melting method was developed for mass production, and the characterization of TiO₂ powder-embedded EPS (TiEPS) balls was evaluated. Based on the scanning electron microscope (SEM) images and associated energy-dispersive X-ray spectroscopy (EDX) analysis, the components of intact EPS balls are carbon and oxygen whereas those of TiEPS balls are carbon, oxygen, and titanium, indicating that TiO₂ powders were embedded on the surface of EPS balls. As also evident by the X-ray diffraction (XRD) and FTIR analyses, no significant changes in crystalline structure of TiO₂ powders embedded on the EPS balls were found during the preparation and application processes of TiEPS balls.

Efficient Spent Sulfidic Caustic (SSC) Wastewater Treatment Using Nano TiO₂-Bottom Ash (NTB) Composite.

Novel composites with nano-sized TiO₂ synthesized on the surface of bottom ash (NTB) were prepared for treatment of spent sulfidic caustic (SSC) wastewater. The efficiency of SSC wastewater treatment was compared and evaluated by using NTBs made with organic binder and inorganic binder, respectively. The treatment efficiency of NTB composite made with organic binder was higher than that of NTB composite made with inorganic binder.

Removal of Humic Acid in Water Using Novel Nanomaterials.

The present study investigates the effectiveness of the photocatalytic degradation of humic acid (HA) in aqueous suspensions. Initial batch scale experiments and tests performed using the Continuous Flow Photoreactor have enabled the close inspection of the performance of the photocatalysts nano TiO2, and nano ZnO dispersions. These photocatalysts were used in aqueous dispersions employing medium-pressure mercury-vapour lamps emitting UV-A (λ = 400 nm) and UV-C (λ = 250 nm).

Preparation of Nanoscale Zinc Oxide-Laponite Composites by Polyvinyl Alcohol Polymerization and Usability for Removal of Trichloroethylene in Water.

Innovative nanoscale ZnO-laponite-polyvinyl alcohol composites (NZLPc) were developed as a valid alternative to nanoscale photocatalysts for mineralization of chlorinated hydrocarbons without difficulties in recovery of nanoscale photocatalyst particles. NZLPc were synthesized by mixing nanoscale ZnO particles with laponite in PVA solution, and by crosslinking PVA solution in the presence of boric acid (≥1.6 M).

Effect of salt type and concentration on the growth and lipid content of Chlorella vulgaris in synthetic saline wastewater for biofuel production.

Microalgae can offer several benefits for wastewater treatment with their ability to produce large amounts of lipids for biofuel production and the high economic value of harvested biomass for biogas and fertilizer. This study found that salt concentration (∼45gL) had more of an effect than salt type on metabolisms of Chlorella vulgaris for wastewater treatment and biofuel production. Salinity stress decreased the algal growth rate in wastewater by 0.

Algal Growth Potential of Microcystis aeruginosa from Reclaimed Water.

Algal growth potential (AGP) of the cyanobacterium Microcystis aeruginosa (M. aeruginosa, NIES-298) using reclaimed water from various wastewater reclamation pilot plants was investigated to evaluate the feasibility of the reclaimed water usage for recreational purposes. After completing the coagulation and ultrafiltration processes, the concentrations of most contaminants in the reclaimed water were lower than the reuse guidelines for recreational water.

Photocatalytic degradation of trichloroethylene in aqueous phase using nano-ZNO/Laponite composites.

The feasibility of nano-ZnO/Laponite composites (NZLc) as a valid alternative to TiO2 to mineralize trichloroethylene (TCE) without difficulties for recovery of photocatalysts was evaluated. Based on the experimental observations, the removal of TCE using NZLc under UV irradiation was multiple reaction processes (i.e.

Modeling sorption of neutral organic compound mixtures to simulated aquifer sorbents with pseudocompounds.

The feasibility of the ideal adsorbed solution theory (IAST) in reducing the complexity associated with predicting the sorption behaviors of 12 neutral organic compounds (NOCs) contained in complex mixtures as a fewer number (four to six) of pseudocompounds (groups of compounds) to simulated aquifer sorbents was investigated. All sorption isotherms from individual- and multiple-pseudocompound systems were fit reasonably well ( ≥ 0.953) by the Freundlich sorption model over the range of aqueous concentrations evaluated (i.

Sorption of nonpolar neutral organic compounds to low-surface-area metal (hydr)oxide- and humic acid- coated model aquifer sands.

The roles of mineral-bound humic acid (HA) and mineral surfaces in the sorption of six nonpolar neutral organic compounds with relatively high aqueous solubility, S(w), (1,2,4-trichlorobenzene, 1,4-dichlorobenzene, chlorobenzene, m-xylene, toluene, and benzene) to low-surface-area (i.e., ≤ 1.