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Zeolites are microporous crystalline aluminosilicates with high surface area and uniform pore size. Natural and synthetic zeolites have been used to adsorb organic and inorganic compounds in aqueous media due to thier particular physicochemical properties and the low cost of the process. The flexibility of zeolites to remove pollutants from water, such as dyes, heavy metal ions, and phenolic compounds, is discussed in this document in the context of contemporary research. This review briefly consolidates the currently available literature to comprehend the structure of zeolites and their synthesized by hydrothermal method. Later, this manuscript is present different parameters to study the adsorption mechanisms of organic and inorganic contaminants using the zeolites. The main adsorption processes using zeolites as adsorbents include chelation, surface adsorption, natural processes, diffusion, electrostatic interaction and complexation. In addition, the research demonstrates that the dominant models in the isothermal and kinetic study of adsorption are the Langmuir and the pseudo-second-order models. We can assess the beneficial applicability of zeolite materials for real wastewater treatment in the future by comparing their adsorption capacities for removing harmful substances from water to those of other adsorbents and crude zeolites.

Water pollution by phenolic composites is considered a major environmental problem. Therefore, their removal by adsorption is of great practical importance. In this paper, the synthesized cobalt oxide Co3O4 was used as an adsorbent for the adsorption of phenol in an aqueous medium. A DFT calculation has been carried out to determine the sites accountable for the interactions in phenol molecule, and molecular dynamics (MD) simulations were used to understand the mechanism of interaction between phenol molecule and Co3O4 surface. The developed adsorbent was characterized by physicochemical methods including XRD, SEM, FT-IR, and BET. The maximum adsorption capacity was observed at pH = 4 with an adsorbed amount of 8.10 mg/g and (R = 98 %). Furthermore, to probe the adsorption action of the phenolic emulsion on the cobalt oxide face, theoretical simulations based on MD (molecular dynamics) and DFT (viscosity functional proposal) were performed. The DFT results verified the chemisorption ascendancy while the MD simulations indicated an increased trade of Co3O4 with phenol in the presence of detergent due to water-bridged H- bonds.

Abstract Five novel pyrazolylnucleosides have been evaluated theoretically for their corrosion inhibition efficiency on the Cu(111) surface in acidic media. DFT calculations were carried out to exhibit the intrinsic properties such as lowest unoccupied (ELUMO) and highest occupied (EHOMO) molecular orbital energies, as well as energy gap (∆E), chemical hardness (η), chemical softness (σ), electronegativity (χ), electrophilicity (ω) and nucleophilicity (ε). The theoretical FT-IR spectra were recorded to indicate the presence of the specific bonds in the studied molecules. The surface interactions between the inhibitor molecules and the metal surface were investigated using molecular dynamics simulations and Monte Carlo (MC) simulations. As a result, we have found that the inhibitor pyrazolylnucleosides 5a–e have strong interactions with Cu(111) surface, and therefore have excellent predictive inhibition power against copper corrosion.

The quantitative structure–property relationship (QSPR) models of the inhibition efficiency of seventeen α-amino acids for copper in acidic medium to their calculated reactivity indicators were developed. DFT calculations and Monte Carlo simulations were employed to find out these indicators. Both multi-linear regression (MLR) and artificial neural network (ANN) methods were employed. The most relevant global descriptors were selected using the simulated annealing algorithm. The QSPR studies showed that the inhibiting performance of the investigated compounds was influenced by their electronegativity, LUMO energy, fraction of electron transferred and total negative charge. The results show that the ANN based model exhibits a great predictive performance compared with MLR model according to correlation coefficient and the root-mean-squared error. In addition, this indicates that the corrosion inhibition of copper by these α-amino acids is mainly a complex phenomenon. Moreover, by analysis of local reactivity indicators and using the ANN constructed model, ten new designed derivative compounds with their predicted inhibition efficiency were proposed. Keywords: Corrosion, Modeling, DFT, Monte Carlo, Simulated annealing, QSPR

According to the literature, the works on the inhibition of aluminum alloy corrosion using naturally occurring compounds are limited. For this, the inhibiting effect of oil mill liquid by-product (OMW) on the corrosion of 3003 aluminum alloy (AA3003) in molar hydrochloric acid solution was evaluated using electrochemical techniques. In parallel, a computational approach based on DFT/B3LYP and Monte Carlo methods was used to understand the inhibition process under electronic and atomic scales, respectively. The experimental results reveal that OMW has a good inhibiting effect on the corrosion of AA3003 alloy in the tested solution and acts as a cathodic inhibitor. The inhibitory efficiency increases by increasing OMW concentration to attain 89% at 6.0 ppm. The effect of temperature shows that the inhibition efficiency of OMW decreases with temperature rising. Nevertheless, a good prevention capacity of 83% is obtained at 338 K. Such interesting achieved protection property was attributed to the adsorption of OMW constituents onto the alloy surface via a mixed physichemisorption process. This process is found to obey the Langmuir adsorption isotherm. Furthermore, the activation thermodynamic parameters of the corrosion process of AA3003 alloy were also determined and discussed. The computational outcomes outlined the ability of the OMW components to interact favorably with the metal surface, hence the formation of a protective layer, which justified the observed inhibition behaviors. Conferring to the present study, OMW can be used as a good green corrosion inhibitor for AA3003 alloy in the acidic medium.

The corrosion of stainless steel is one of the major industries’ issues that gained wide interest among researchers. It became necessary to develop and apply eco-friendly approaches to corrosion control. This work explores the inhibitory effect of a newly synthesized amino cadalene (ACM) on the corrosion of stainless steel type 321 in sulfuric acid 1M. Particularly, the experimental study consisting of electrochemical and surface analyses was conducted in conjunction with a theoretical approach. The electrochemical results showed that ACM acted as a mixed-type corrosion inhibitor and the inhibition efficiency attained 91% at 10−3M. EIS measurements revealed that both metal charge transfer and diffusion processes are involved in the interfacial metal/solution reactions. The interfacial mechanism is thoroughly investigated; the physisorption of the protonated molecules was preceded by the formation of a negative layer due to adsorption of the solution anionic species. The experimental insights are corroborated with the quantum chemical calculations.

AB5 compounds issued from the reactivity of hexachlorocyclotriphosphazene are relatively easy to obtain using two ways: either first the reaction of one chloride with one reagent, followed by the reaction of the five remaining Cl with another reagent, or first the reaction of five chlorides with one reagent, followed by the reaction of the single remaining Cl with another reagent. This particular property led to the use of such compounds as core for the synthesis of dendrons (dendritic wedges), using the five functions for growing the dendritic branches. The single function can be used for the synthesis of diverse types of dendrimers (onion peel, dumbbell-shape, Janus), for covalent or non-covalent grafting to solid surfaces, providing nanomaterials, for grafting a fluorophore, especially for studying biological mechanisms, or for self-associations to get micelles. All these properties are reviewed in this paper.