Acta Chemica Malaysia

Journal: Acta Chemica Malaysia (ACMY)
Author: Ng Boon Swan and Muhammad Abbas Ahmad Zaini
ISSN: 2576-6732
e-ISSN: 2576-6724

This is an open access journal distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: https://doi.org/10.2478/acmy-2019-0004

The present work was aimed at evaluating the adsorption properties of malachite green and congo red dyes by polyacrylonitrile carbon fibre sorbents. The sorbents were activated and oxidized using potassium hydroxide and ammonium persulfate, respectively at mild conditions. Consequently, the sorbents were characterized for surface area, surface functional groups and thermal decomposition. The activated sorbent displayed a 18.8 mg/g (94 %) of malachite green removal at Co = 20 mg/L, while both modified sorbents showed a 17.5 mg/g (87.5 %) removal of congo red at the same concentration. All sorbents showed a rapid equilibrium of malachite green and congo red dyes in water. Also, the sorbents are somewhat tolerable against different solution pH conditions despite a slight change due to possible electrostatic interactions. Thus, the materials could be successfully employed to treat dyes-laden wastewater.

Journal: Acta Chemica Malaysia (ACMY)
Author: Vandana Singh, Manager Rajdeo Singh
ISSN: 2576-6732
e-ISSN: 2576-6724

This is an open access journal distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: https://doi.org/10.2478/acmy-2019-0003

This investigation deals with the chemical composition and microstructural analysis of the iron object, a spear excavated from Sanur, Tamil Nadu- a megalithic site dated 300 B.C. to 50 A.D. Phase analysis and microstructural examination were carried using XRD, optical and variable pressure scanning electron microscope (VP-SEM). Optical micrograph shows the equiaxed grain structure along with the Newman bands. Formation of Newman bands suggests that the original artifact was forged at high temperature followed by cooling, although not so rapid to produce the marked hardening. The absence of carbides at the grain boundary, within the grains and lower value of micro-hardness indicates that the iron spear was not subjected to the carburizing treatment. Results of corrosion characterization revealed that deterioration of excavated iron artifact is associated with the presence of chlorine in corrosion products. However, compact nature of the outer rust (goethite) was helpful in protecting the object. The formation of goethite [ ∝-FeOOH] layer may prevent the iron matrix suffering from attacks by other environmental factors due to its good continuity. In addition, less aerated environment of storage and no history of any cleaning of object were also helpful in preventing the iron spear from further deterioration.

Journal: Acta Chemica Malaysia (ACMY)
Author: Kaywood Elijah Leizou and Muhammad Aqeel Ashraf
ISSN: 2576-6732
e-ISSN: 2576-6724

This is an open access journal distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

DOI: https://doi.org/10.2478/acmy-2019-0002

This study was carried out to investigate the distribution and contents of sixteen priority polycyclic aromatic hydrocarbons (PAHs) in water from Amassoma axis of the Nun River, Bayelsa State, Nigeria. The PAH contaminations in the river water samples was performed using GC-MS method. The results were similar for all of the three sampling stations. Six LMW PAHs: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene and five HMW PAHs: fluoranthene, pyrene benzo (a)anthracene, chrysene and benzo(a)pyrene were found. The ∑ PAHs concentration ranged from 0.111mg/L to 0.26mg/L. In this study, PAH fingerprint ratios for determining both petrogenic and pyrogenic (pyrolytic) PAH accumulation in the environment and Toxic equivalency factor (TEF) used to estimate relative toxicity of a PAH compared to that of BaP was employed. The Ph/An ratio for water samples were 0.00, 0.33 and 0.00 in three stations, while associated figures for Fl/Py ratio values were 0.67, 0.83 and 0.50 respectively. Pearson correlation matrice analysis reveals a positive correlation between the PAHs; this could indicate a common source for some of the PAHs, however, some were negatively correlated with each other. This behavior could indicate non-point source. A comparative analysis of PAHs concentrations in the water samples with WHO standards revealed that the results obtained in this study were within the permissible levels, however, carcinogen PAHs present in the water of the Amassoma axis, Nun River may pose a threats to human health.