Characterization of electrocatalytic proton reduction and surface adsorption of platinum nanoparticles supported by a polymeric stabilizer on an ITO electrode

Platinum nanoparticles (PAA-Pt) stabilized by polyacrylic acid (PAA) of a polymeric stabilizer were adsorbed on an indium tin oxide (ITO) surface from their colloidal solution due to the chemical adsorption...

Preparation of Amine-Modified Cu-Mg-Al LDH Composite Photocatalyst

Cu-Mg-Al layered double hydroxides (LDHs) with amine modification were prepared by an organic combination of an anionic surfactant-mediated method and an ultrasonic spalling method using N-aminoethyl-γ-aminopropyltrimethoxysilane as a grafting agent. The materials were characterized by elemental analysis, XRD, SEM, FTIR, TGA, and XPS. The effects of the Cu2+ content on the surface morphology and the CO2 adsorption of Cu-Mg-Al LDHs were investigated, and the kinetics of the CO2 adsorption and the photocatalytic reduction of CO2 were further analyzed. The results indicated that the amine-modified method and appropriate Cu2+ contents can improve the surface morphology, the increase amine loading and the free-amino functional groups of the materials, which were beneficial to CO2 capture and adsorption. The CO2 adsorption capacity of Cu-Mg-Al N was 1.82 mmol·g−1 at 30 °C and a 0.1 MPa pure CO2 atmosphere. The kinetic model confirmed that CO2 adsorption was governed by both the physical and chemical adsorption, which could be enhanced with the increase of the Cu2+ content. The chemical adsorption was suppressed, when the Cu2+ content was too high. Cu-Mg-Al N can photocatalytically reduce CO2 to methanol with Cu2+ as an active site, which can significantly improve the CO2 adsorption and photocatalytic conversion.

Applying first principles to study the structural, electronic, and magnetic properties of Pr adsorbed ASiNRs

Applying first-principles calculations, the investigation of the geometrical and electronic properties of Pr adsorption armchair silicene nanoribbons structure has been established. The results show that the bandgap doped Pr has been changed, which is the case for chemical adsorption on the surface of ASiNRs; this material became metallic with the peak of valance band contact fermi level. Moreover, the survey to find the optimal height 1.82 Å of Pr and 2.24 Å bond length Si-Si, and Si-Si-Si bond angle 108005’, energy adsorption is -7.65 eV, buckling is 0.43 Å with structure stability close to the pristine case, has brought good results for actively creating newly applied materials for the spintronic and optoelectronics field in the future.

Computer prediction of technological modes of rapid cone-shaped adsorption filters with automated discharge of part of heat from separation surfaces in filtering mode

In the paper a mathematical models of technological modes of filtration with automated removal of part of heat from interface surfaces (water purification from multicomponent impurities), backwashing, chemical regeneration and direct washing of rapid cone-shaped adsorption filters with chemical regeneration of piecewise homogeneous porous loads while maintaining constant velocities of the respective modes is formulated. The proposed models in the complex allow to conduct computer experiments to investigate the change in the concentrations of components of a multicomponent impurity in the filtration stream and on the surface of the loading adsorbent, retained by both physical and chemical adsorption, filtration flow temperature, filtration coefficient, active porosity and pressure along the filter height and on their basis to predict more optimal options for the use of adsorbents of each loading layer and increase the protective time of rapid cone-shaped adsorption filters with automated heat removal from the interface surfaces in filter mode.

Application of Waste Engine Oil for Improving Ilmenite Flotation Combined with Sodium Oleate Collector

Collectors commonly have synergetic effects in ores flotation. In this work, a waste engine oil (WEO) was introduced as a collector to an ilmenite flotation system with sodium oleate (NaOL). The results show that the floatability of ilmenite was significantly improved by using WEO and NaOL as a combined collector. The recovery of ilmenite was enhanced from 71.26% (only NaOL) to 93.89% (WEO/NaOL combined collector) at the pH of 6.72. The optimum molar ratio of NaOL to WEO was about 2.08 to 1. The WEO and NaOL also have synergetic effects for the collection of ilmenite, because to obtain the ilmenite recovery of 53.96%, the dosage of 45 mg/L NaOL is equal to 38.56 mg/L WEO/NaOL combined collector (30 mg/L NaOL + 8.56 mg/L WEO). In other words, 15 mg/L of NaOL can be replaced by 8.56 mg/L of WEO. It is an effective way to reduce the dosage of the collector and reuse WEO. Therefore, it is a highly valuable and environmentally friendly approach for WEO reuse. WEO mainly consists of oxygen functional groups, aromatics, and long-chain hydrocarbons, especially for the RCONH2 and RCOOH, thereby forming a strong interaction on the ilmenite surface. The adsorption mechanism of waste engine oil and sodium oleate on the ilmenite surface is mainly contributed by chemical adsorption. Therefore, WEO exhibits superior synergistic power with NaOL as a combined collector. Herein, this work provided an effective collector for ilmenite flotation and a feasible approach for reducing NaOL dosage and recycling WEO.

Adsorption Configurations of Iron Complexes on As(III) Adsorption Over Sludge Biochar Surface

Waste recycling and reuse will result in significant material and energy savings. In this research, usage of hospital sludge as a biochar adsorbent for wastewater treatment plants was investigated. Microwave carbonization was used to carbonize the sludge and then chemically activated with ZnCl2to increase surface area and porosity. A newly designed iron metal doped sludge biochar carbon (SBC) has effective adsorption of inorganic arsenic (As(III), As2O3) in water. The findings clearly demonstrate the viability and utility of using hospital sludge as a source of carbon to generate SBC. The adsorption mechanism of As(III) on SBC’s iron-metal-modified surface has been studied using density functional theory (DFT) to understand the impact of functional complexes on adsorption As(III). Tests showed physical as well as chemical adsorption of As(III) on Fe-SBC surface. Fe’s involvement in functional complexes greatly fostered SBC surface activity and it’s As(III) adsorption ability. The physical adsorption energies of As(III) with Fe functional complexes on the SBC surface were −42.3 KJ mol−1. Other hand, the chemical adsorption energies of As(III) on Fe-SBC surface was −325.5 KJ mol−1. As(III) is capable of interacting in a bidentate fashion with the dopants through the protonated oxygen atoms and this conformation of the cyclic structure is higher in the adsorption energy than the others.