Search

Efficiently processing volatile organic compounds (VOCs) with nonthermal plasma and honeycomb catalyst for practical industrial applications presents a sizable challenge. An attempt has been made to generate a large volume of uniform plasma at atmospheric pressure in a practical-scale honeycomb catalyst. H-ZSM-5, a type of zeolite, was washcoated on a commercial bare honeycomb monolith as the catalyst-supporting material, after which the monolith was impregnated with Pd. The plasma discharge power can be controlled by controlling the humidity in the feed gas, metal content, applied voltage, and total flow rate of the feed gas. The plasma was characterized by the voltage and current waveforms, and optical emission spectroscopy (OES). In this study, 85% of dilute toluene (15 ppm) was successfully removed from an airstream at a large flow rate of 60 L/min with an energy density of 84 J/L. Under this condition, the selectivity of CO2 was 76%. This investigation demonstrated the practical applicability of the plasma-honeycomb catalytic reactor to process a fast-flowing feed gas without resulting in a significant large pressure drop, which can hardly be achieved with typical packed-bed plasma reactors.

BES for H2O2 production has great potential in the future due to its high efficiency, energy efficiency, and environmental friendliness because it turns waste into useful chemicals without any energy input.

Combined calcination (700 °C) and extraction was applied for aluminum recovery from alum sludge (AS) for phosphorus removal. Calcined AS had higher aluminum and lower COD content than the intact and dried AS. Both acid and alkali extraction recovered more than 90% of the aluminum in the intact and the pretreated AS. Alkali extract of the AS had less heavy metals and COD contents than the acid extract. Response surface methodology (RSM) of Box–Behnken Design (BBD) was applied to find the optimal condition for phosphorus removal with the recovered aluminum solutions. The aluminum solutions showed that the highest phosphorus removal efficiency was more than 98% at the optimal condition (pH 6.4 and Al/P molar ratio higher than 2) with the extract from the calcined AS. FTIR and XRD analyses confirmed that the recovered precipitate contained AlPO4 and Al(OH)3.

Herein, cherry flower waste-derived activated carbon (CFAC) with self-doped nitrogen is synthesized as a viable energy storage material for green and sustainable energy solutions. The activated carbon derived in this way is examined as an electric double-layer capacitance (EDLC)-type electrode material and sodium-ion battery (NIB) electrode material, and commendable performance is demonstrated for both of these energy storage applications. The specific surface area (SSA) and nitrogen content are observed to play a very delicate role in determining the charge storage ability of the CFAC, and the performance is optimized only by carefully balancing both of these properties. The optimized CFAC electrode supplied an excellent performance with a specific capacitance of 333.8 F g

The deformable electronic devices such as flexible, foldable, bendable, wearable, etc., are deemed the future of portable electronics, which could only be realized through the proper design of an energy storage unit that could power them. Herein, we report the conception of an ultrastable, binderless flexible electrode/substrate configuration that can be implemented in various energy storage applications such as supercapacitors, lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, and alike. Firstly, the conductive carbon fabric was electrochemically deposited with nickel nanospheres; then the ZIF-67 metal-organic framework (MOF) promoted metal hydroxide nanostructures were grown over the Ni-CCF substrate. As grown nanostructures were then embedded inside the CCF through a meticulous optimization process varying the calcination temperature and gas concentrations. The metal seed embedded CCF was then coated with the hydrocarbons, the precursors of which are generally known volatile organic compounds and pollutants such as C2H4, CH4, CO2, and NH3 through the dielectric barrier discharge (DBD) plasma at atmospheric pressure and temperature. The carbonization of the final product results in the ultra-robust flexible electrode with metal-oxide nano seeds embedded CCF, coated with ~20nm nitrogen-doped carbon thin film which will be an excellent electrode material for an ultra-long life flexible energy storage system. Figure 1

Reverse electrodialysis (RED), based on non-precious electrodes, was applied to disinfect domestic aquaculture wastewater. It was found that treatment could be achieved either by an anodic reaction of electro-generated sodium hypochlorite (NaClO) or via a cathodic reaction of electro-generated hydrogen peroxide (H2O2). Without circulation, the disinfection rate was sub-optimal and depended on the anodic and cathodic reactions, reaching 82 ± 5% at the anode (0.3–2.9 mg/L of chlorineDPD, pH 3.2 ± 0.4) and 59 ± 7% at the cathode (2.9–8.7 mg/L of H2O2, pH 10.7 ± 0.3). In contrast, a high removal efficiency of ≥99 ± 1% was obtained when anodic and cathodic solutions were circulated due to the synergetic effect between HClO and H2O2 (0.1–2.1 mg/L of chlorineDPD, 3.9–4.9 mg/L of H2O2, pH 7.8 ± 0.2). Both operating modes resulted in a stable power production of 6 ± 0.5 W/m2. These results support the view that RED can offer a cost-effective and energy-efficient option for disinfecting aquaculture wastewater.

A practical-scale sandwich-type honeycomb catalyst reactor incorporating non-thermal plasma was developed for the high-throughput removal of isopropanol (IPA) from air. The Pd/γ-Al2O3/honeycomb catalyst was fabricated by coating a cordierite monolith with γ-alumina powder on which to support the palladium (Pd). The supported catalyst showed good activity and the combination of the honeycomb structure with plasma produced a uniform plasma inside the catalyst chamber. The influence of different parameters, including the energy density (SIE), humidity, initial concentration, and flow rate, on the plasma characteristics and IPA removal efficiency was investigated. The results showed that the SIE has the strongest effect on the IPA removal efficiency. The efficiency of IPA removal was 94.5% and the CO2 selectivity was 85% for an SIE of 180 J/L. Using optical emission spectroscopy, we found that the increased formation of atomic oxygen and reactive species plays an essential role in the oxidation of IPA by plasma catalysis. The main byproducts were identified by GC-MS, which indicated that acetone is the major liquid product. A plausible reaction mechanism for the plasma-catalytic oxidation of IPA is proposed based on the intermediates and byproducts.

In this work, sustainably synthesized metal-organic framework (MOFs) MIL-100 (Fe) nanoparticles were incorporated into polysulfone (PSF) matrix to fabricate a novel PSF/MIL-100 (Fe) composite membrane. Compared to the pristine PSF membrane (M0), incorporation of the hydrophilic MIL-100 (Fe) nanoparticles significantly altered the membrane morphology, hydrophilicity (water contact angle reduced to 64.2° ± 1.2 from 84.6° ± 1), work of adhesion (WA), wetting energy (WE), porosity, and pore size. Furthermore, loading 0.5 wt% of MIL-100 (Fe) particles into the PSF matrix (M0.5) was found to deliver the uppermost performance relative to the membranes with other loadings. Those above mentioned, M0.5 membrane comprise superior pure water flux (10.3 times higher than M0) with more than 99% rejection efficiency of methylene blue (MB) and excellent anti-fouling performances for MB dye, microplastics (MPs) + MB dye solutions. Furthermore, the M0.5 membrane sustained an outstanding performance at various concentrations of MB dye, MPs, and a range of transmembrane pressures (TMPs). In addition, the membrane exhibited moderate salt rejection efficiency and reusability for as many as six cycles of MB dye rejection without compromising the permeability and anti-fouling performances. Overall, the fabricated PSF/MIL-100 (Fe) composite membrane proposed an efficient route to separate the contaminants from textile wastewater.

The purification of hazardous textile dyeing wastewater has exhibited many challenges because it consists of a complex mixture, including dyestuff, additives, and salts. It is necessary to fabricate membranes with enhanced permeability, fouling resistance, stability, and superior dyes and salts removal from wastewater. Incorporating a highly water stable metal-organic framework (MOFs) into membranes would meet the requirements for the efficient purification of textile wastewater. In this study, nanofiltration (NF) membranes are fabricated by incorporating MIL-100 (Fe) into the chitosan (CS) through film casting technique. The effect of MIL-100 (Fe) loadings on chitosan characterized by FT-IR, XRD, contact angle measurement, FESEM-EDS, XPS, zeta potential, and surface roughness analysis. The membrane characterization confirmed the enhanced surface roughness, pore size, surface charge, and hydrophilicity. The CS/MIL-100 (Fe) membrane exhibited an improved pure water flux from 5 to 52 L/m2h as well as 99% rejection efficiency for cationic methylene blue (MB) and anionic methyl orange (MO). We obtained the rejection efficiency trend for the MB mixed salts in the order of MgSO4 (Mg2+ - 51.6%, SO42− - 52.5%) > Na2SO4 (Na+ - 26.3%, SO42− - 29.3%) > CaCl2 (Ca2+ - 21.4%, Cl− - 23.8%) > NaCl (Na+ - 16.8%, Cl− - 19.2%). In addition, the CS/MIL-100 (Fe) composite membrane showed excellent rejection efficiency and antifouling performances with high recycling stability. These stunning results evidenced that the CS/MIL-100 (Fe) nanofiltration membrane is a promising candidate for removing toxic pollutants in the textile dyeing wastewater.