Asian Journal of Green Chemistry
Volume:5 Issue: 2, Spring 2021

In this work, Zn2Al-layered double hydroxide (LDH) that modified with Ponceau 4R (E 124) as food coloring, (Zn2Al-LDH/Ponceau) was synthesized and characterized  using different techniques including, X-ray diffraction analysis (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray (EDX) spectroscopy. Zn2Al-LDH/Ponceau was then applied for Cd2+ removal from aqueous solution. The response surface methodology (RSM) approach using central composite design (CCD) was applied to develop a mathematical model and optimize process parameters for Cd2+ removal from aqueous solution using a chemically modified Zn2Al-LDH/Ponceau. The optimal conditions to remove Cd2+ from aqueous solution were found to be initial Cd2+ concentration of 76 mg.L-1, pH value of 4.22, adsorbed amount of 0.04 g, temperature of 30.3 °C, and the contact time of 46 min. The isotherm and kinetics and thermodynamics of the adsorption were investigated in detail. The obtained results suggested the adsorption of Cd2+ onto Zn2Al-LDH/Ponceau follow Langmuir isotherm and the kinetic data are in good agreement with the Elovich kinetic model. In addition, the results of thermodynamic parameters indicated that the adsorption process was instantaneous nature and exothermic.

In the pharmaceutical arena, the most significant issue is green technology. This is due to the fact that, it decreases the cost of drugs, reducing the environmental influence of the arena and improving the human health and safety. Deep eutectic solvents (DES), a novel kind of green solvent, have some focused attributes such as, low vapor pressure, high thermal stability, low cost, biodegradability, and high viscosity. Green solvent metrics with attention to functionality and environmental, safety, and health influences from a progression and life cycle view are likewise addressed and practical to common and unique solvents.As a developing research field, DESs have previously received important research consideration from chemistry scientists.

Surface tension, conductivity, and ultraviolet spectroscopic methods have been employed to study the dimensional fit molecular encapsulation of hydrazinophthalazine hydrochloride insight into the cavity of β-cyclodextrin in aqueous media. The equilibrium constant and 1:1 stoichiometry of the complex has been analyzed by surface tension (plot against reciprocal of concentration), and Job’s plot (drawn from UV-vis data). The binding constants computed from the tensiometric and spectroscopic method were found to be 59.91 μM-1 and 12.02-96.58 μM-1, respectively, that return the comfort zone of the results. The noteworthy upshot has also come out from standard Gibbs energy for inclusion complex formation. The free energy for inclusion complex is negative and lower in magnitude than adsorption by 6.11 kJ mol-1. 1HNMR and SEM picture also certified the formation of the inclusion complex. The results demonstrated that the driving force for formation of the inclusion complex inside the bucket-like cavity of β-cyclodextrin was a combination of hydrophobic effect and reduction of the surface energy, while in adsorption is only hydrophilic effect.

Coumarins are oxygenated heterocycles that play a structural role in many natural products and have numerous biological activities and therapeutic applications, including anticoagulant activity, antiviral activity, use as an antibiotic, spasmolytic activity, antimicrobial activity, anticancer activity, and antioxidant activity. They also have antifungal, anti-insect, and anti-inflammatory properties and are employed to prevent disease and regulate growth. In addition, they are utilized as food additives and cosmetics. Due to the critical applications of coumarin derivatives, the synthesis of these compounds is of great importance. In this research study, the CeO2 nanocatalyst was exploited as an available catalyst that is also thermally stable in the synthesis of these compounds.

This paper presents removal of some polycyclic aromatic hydrocarbons (PAHs) by silver nanoparticles (AgNPs) which were synthesised by garlic based green route method. Allivum sativum (Garlic) extract was used for the synthesis of silver nanoparticles Ag(P) as a green route process while synthetic chemical method was adopted for preparation of silver nanoparticles Ag(W). The synthesis of AgNPs was studied as a function of variation in volume of garlic extract, temperature and time. Solution of pyrene, anthracene and phenanthrene was prepared in n-hexane, and their removal efficiencies were studied. PAHs were removed successfully with optimal efficiency of more than 80% with the affinity order of removal, which followed Phenanthrene > Pyrene > Anthracene. The adsorption of PAHs on AgNPs is attributed to the occurrence of hydrophobic interactions. Ag (P) nanoparticles synthesized were found relatively better adsorbent than Ag (W), for removal of PAHs. It may be ascribed owing to the presence of more functional groups in the garlic extract participating in binding of PAH to the surface. The adsorption property of the AgNPs synthesized by both ways was studied and comparative results were obtained based on adsorption efficiency of PAHs. Further, FTIR and XRD were used to characterize the properties of garlic extract with binding and interaction taking place between AgNPs and PAHs. UV-Vis confirmed the formation of Ag(P) and Ag(W) by biological method and chemical wet co-precipitation method, respectively. Ag(P)can be applied over a wide range of temperature, due to stability of compounds present in Allivum sativum at high temperatures.

< p>In this study, zinc oxide (ZnO) nanoparticles (NPs) were first synthesized using the co-precipitation method at the presence of Zn(NO3)2.6H2O precursor and calcined at 450 °C and 1000 °C. Then, the samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). The XRD analysis was performed to evaluate the crystal structure. SEM and TEM analyses were also conducted to assess the morphology and the particle size of the material. Finally, the chemical compositions of the samples were investigated by energy dispersive x-rays (EDX) analyses. In this work, the crystallite Polygon shape ZnO NPs were fabricated in the range of 70-100 nm. We found that the intensity of the crystal plane of (002) increased by raising the temperature to 1000 °C.

Microwave heating has been adopted as green approach for the synthesis of bohmite (AlO(OH)) and brucite (Mg(OH)2) nanoparticles (NPs) for antifungal activity. The synthesis of AlO(OH) and Mg(OH)2 NPs were carried out at 150 °C and the resulting NPs have an average diameter of 10-20 nm. The Mg(OH)2 and AlO(OH)  have trigonal and orthorhombic crystal structure, respectively. The antifungal activity of the synthesized NPs was assessed using the Penicillium Expansum (P. expansum) through agar well diffusion method. The Mg(OH)2 and AlO(OH) revealed comparable significant antifungal activities towards P. expansum. About 79% and 74% reduction in the growth of the fungus was obtained respectively of AlO(OH) and Mg(OH)2 as compared to the standard control haxahit. Nanomaterials bind on the surface of the fungi thereby preventing the normal activity of fungi and inhibit their growth, ultimately kill them. Reported NPs have significant potential to replace expensive nanomaterials in the field of antimicrobial studies.

An efficient catalytic system for analyzing Pyrazine derivatives using an extract of onion at room temperature is discussed in this research study. A very good to excellent yields in reasonably short reaction time, high atom economy, usage of readily available starting material, operational simplicity and easy workup are the fundamental features of this protocol. The versatility our method is determined by synthesizing a large number of pyrazine derivatives with (85-96%) good yield.