Open Access Systematic Review Article

Study of Reactivity and Molecular Stability by the Density Functional Theory Method on 2,3-Dihydro -1H-Perimidine: Comparative Analysis

Tuo Nanou Tiéba, Soro Doh, Konate Bibata, Kodjo Charles Guillaume, Yapo Ossey Bernard, Ziao Nahossé

Chemical Science International Journal, Page 29-37
DOI: 10.9734/CSJI/2021/v30i430227

Numerous studies have been carried out on the structure of 2,3-dihydro-1H-perimidine substituted as compounds with various biological activities. Researchers have found that these compounds exhibit characteristics potentially useful in medicinal chemistry research and have many therapeutic applications. In this work, we carried out a study using descriptors of the conceptual DFT in order to determine the atoms responsible for the chelation of certain metals (zinc, copper, iron ...) in order to propose new stable molecules complexed with these metals. Calculations were performed to determine the local reactivity of substituted 2,3-dihydro-1H-perimidine using Fukui functions by the Natural Population Analysis method. Overall parameters were also determined to predict the relative stability and reactivity of substituted 2,3-dihydro-1H-perimidine. This work was carried out at the calculation level B3LYP / 6-311G (d, p). Compound 2 with an energy difference from the frontier orbitals of ΔEgap = 4.031 eV is the most polarizable. Also, the study of frontier orbitals locates HOMO on the function of substituted 2,3-dihydro-1H-perimidine. Analysis of local reactivity indices as well as of the dual descriptor revealed that nitrogen N17 and N19 are the most favorable sites for electrophilic attack.

Open Access Original Research Article

Optimization of the Production of Ethylene Di-Amine Tetra-Acetic Acid Modified Activated Carbon using Palm Kernel Shell for the Adsorption of Copper ion

Y. Yerima, I. Eiroboyi, I. Eiroboyi

Chemical Science International Journal, Page 1-11
DOI: 10.9734/CSJI/2021/v30i430224

Biomass-based activated carbon has received large attention due to its excellent characteristics such as inexpensiveness, good absorption behaviour, and potential to reduce strong dependence towards non-renewable precursors. The potential use of Palm Kernel Shell in modified activated carbon was evaluated by using the Response Surface Methodology. In this study, a 23 three-level Central Composite Design (CCD) was used to develop a statistical model for the optimization of process variables, contact time (10-130mins) X1, pH (5.0 – 8.0) X2, and adsorbent dose (0.4 -5.0g) X3. The investigation shows that Ethylene Di-Amine Tetra-Acetic Acid modified activated carbon prepared from Palm Kernel Shell is a promising adsorbent for the removal of copper ions from aqueous solutions over a wide range of concentrations with an optimized efficiency of 99% at the solution pH of 7.2, contact time of 70 minutes and adsorbent dose of 2.1g/L. The adsorption results are in line with the linear and quadratic model representation, which is evident from the models for optimization of copper ions.

Open Access Original Research Article

Electrochemical Detection of 4-Nitrophenol on a Nanoporous Gold Electrode Prepared by One-Step Anode Potential Step Method

Dongsheng Lai, Lin Chen, Yuqing Liu, Wei Huang

Chemical Science International Journal, Page 12-19
DOI: 10.9734/CSJI/2021/v30i430225

The wastewater containing nitrophenol compounds is discharged into the water and soil environment, causing severe environmental pollution problems. In this paper, a one-step anodic potential step method involving Au(I) disproportionation was used to prepare nanoporous gold (D-NPG) electrodes for the electrochemical detection of 4-nitrophenol (4-NP) by differential pulse voltammetry (DPV). The D-NPG electrode has a high current response to the oxidation peak of 4-hydroxylaminophenol, a product of 4-NP electroreduction. This peak is used in the 4-NP detection. Under the optimized conditions, the resulting detection range is wide (0.01~20 µM) and the detection limit is low (3.5 nM), and its anti-interference ability is good. It can be used for the electrochemical detection of 4-NP in real water samples.

Open Access Original Research Article

Characterization of Water Quality on University Campus

Doris Fovwe Ogeleka, Mildred Chukwuedum Emegha

Chemical Science International Journal, Page 20-28
DOI: 10.9734/CSJI/2021/v30i430226

Introduction: Safe drinking water is vital to all human and living organisms.

Aim and Study Location: This study appraised untreated water within the Federal University of Petroleum Resources, Effurun (FUPRE) campus with a view to ascertaining their potability.

Methodology: The samples were analyzed using the America Public Health Association (APHA), standard protocol

Results: The pH indicated that the water were acidic with pH values from 3.50 ± 0.04 to 5.73 ± 0.08. Total iron exceeded the stipulated WHO limit of 0.3 mg/L in some of the locations with concentration varying from 0.232 ± 0.01 to 0.963 ± 0.04. The heavy metal load was relatively low and within regulatory limits.

Conclusion: The study concluded that water should not be consumed without treatment due to the non-conforming parameters. In addition, waters with a non-conformance contributed by feacal coliform (E coli) or any other microbial entities should be avoided since serious health water-related diseases (cholera, typhoid, dysentery and diarrheal) may set if consumed.

Open Access Original Research Article

Effects of Different Types of Zeolites on the Degradation Kinetics of Malathion Pesticide in Water

Elly Tety Osewe, Victor Shikuku, Cristiane A. Pereira, Stephen O. Otieno, Audrey Okoyo

Chemical Science International Journal, Page 38-49
DOI: 10.9734/CSJI/2021/v30i430228

The study examined the effects of selected types of zeolites as an environmentally benign and friendly way to degrade, S-1, 2-bis (ethoxycarbonyl) ethyl O, O-dimethylphosphorodithioate (malathion), used as a model pesticide, from river water. The effect of the size of zeolite channels and dimensionality (such as 1D, 2D, and 3D), Si/Al ratio, and operating pH were studied to find a suitable type of zeolite and conditions to optimize the pesticide degradation. Mordenite (MOR (1D): Si/Al=6.83, and Si/Al=10.72), ferrierite (FER (2D): Si/Al=10.71), ZSM-5 (MFI (3D): Si/Al=6.83 and Si/Al=10.72) and USY (FAU (3D): Si/Al=2.77) zeolites were individually mixed with a water sample collected from Monjolinho River in São Carlos (SP), Brazil and the degradation trend studied. The results showed that all the zeolites accelerated the degradation of malathion. Nevertheless, lower zeolite Si/Al ratio and larger 3D channels or cavities had a positive influence on the degradation rate. The FAU zeolite presented the stronger degradation of the malathion with a half-life of 16.5 followed by ZSM-5 with 24.8, ferrierite with 29.7, and finally mordenite with 30.3 hours.