Reusable isotype heterojunction g-CN/alginate hydrogel spheres for photocatalytic wastewater treatment.

Various visible-light-driven photocatalysts have been studied for practical applications in photocatalytic wastewater treatment solar irradiation. Among them, g-CN has attractive features, including its metal-free and environmentally friendly nature; however, it is prone to charge recombination and has low photocatalytic activity. To solve these problems, isotype heterojunction g-CN was recently developed; however, the methods employed for synthesis suffered from limited reproducibility and efficiency.

Nitrogen removal from wastewater by an immobilized consortium of microalgae-bacteria in hybrid hydrogels.

The high content of nitrogen in wastewater brings some operational, technical, and economical issues in conventional technologies. The aim of this study was to evaluate the nitrogen removal by hybrid hydrogels containing consortium microalgae-nitrifying bacteria in the presence of activated carbon (AC) used as an adsorbent of inhibitory substances. Hybrid hydrogels were synthesized from polyvinyl alcohol (PVA), sodium alginate (SA), biomass (microalgae-nitrifying bacteria), and AC.

Advanced light-tolerant microalgae-nitrifying bacteria consortia for stable ammonia removal under strong light irradiation using light-shielding hydrogel.

The consortium of microalgae and nitrifying bacteria has attracted attention owing to its advantages, such as energy- and cost-efficiency in terms of using only light irradiation without aeration. However, high light intensity can easily cause photoinhibition of nitrifying bacteria, resulting in process breakdown of the consortium. This challenge limits its practical application in outdoor environment.

Cumulative effects of titanium dioxide nanoparticles in UASB process during wastewater treatment.

Titanium dioxide nanoparticles (TiO NPs) are widely used in consumer products and one of their major fate is the wastewater treatment plants. However, NPs eventually arrive to aquatic and terrestrial ecosystems via treated water and biosolids, respectively. Since low concentration of NPs is accumulating in the upflow anaerobic sludge blanket (UASB) reactors that treat wastewater and reclaim water quality, the accumulation of TiO NPs in these reactors may impact in their performance.

Effects and fate of TiO nanoparticles in the anaerobic treatment of wastewater and waste sludge.

The increasing use of TiO nanoparticles (NPs) in customer products has also increased the concerns about their effects in the environment. Anaerobic digestion is a process probably exposed to high concentrations of TiO NPs due to its application for wastewater and waste sludge treatment. In this work, it was studied the anaerobic digestion performance and the extracellular polymeric substances (EPS) production in presence of TiO NPs, as well as the fate of TiO NPs in anaerobic reactors.

Influence of wastewater type on the impact generated by TiO nanoparticles on the oxygen uptake rate in activated sludge process.

Physicochemical characteristics of wastewater have a relationship with the stability of TiO nanoparticles (NPs). This in turn has an effect on the toxicity of TiO NPs in microorganisms. In this work, the effect of TiO NPs on activated sludge process was evaluated using three different types of wastewater: synthetic, raw, and filtered.

Tailoring pore properties of MCM-48 silica for selective adsorption of CO2.

Four different types of amine-attached MCM-48 silicas were prepared and investigated for CO(2) separation from N(2). Monomeric and polymeric hindered and unhindered amines were attached to the pore surface of the MCM-48 silica and characterized with respect to their CO(2) sorption properties. The pore structures and amino group content in these modified silicas were investigated by XRD, FT-IR, TGA, N(2) adsorption/desorption at 77 K and CHN/Si analysis, which confirmed that in all cases the amino groups were attached to the pore surface of MCM-48 at 1.

Mechanism of high-temperature CO2 sorption on lithium zirconate.

Lithium zirconate (Li2ZrO3) is one of the most promising materials for CO2 separation from flue gas at high temperature. This material is known to be able to absorb a large amount of CO2 at around 400-700 degrees C. However, the mechanism of the CO2 sorption/desorption process on Li2ZrO3 is not known yet.