Asian Journal of Applied Chemistry Research

Opals are naturally occurring hydrous silica materials (SiO2*nH2O), and have been largely used in jewelry and as decorative elements in artworks due to their optical properties. In this study, we present some gemological properties, a combined spectroscopic (FAAS, FTIR) and X-ray powder diffraction (XRD) identification of natural and heat treated opals obtained from the main deposits in North Wollo, Ethiopia. The gemological measurements, FTIR and XRD spectra for natural and heat treated samples are nearly identical, FAAS shows clear differences on their color this may be due to the concentration differences of metals. Both of these opals showed spectra and diffraction patterns typical of Opal-CT, with clearly defined patterns and main peaks in the 2θ range of cristobalite and tridymite, called microcrystalline opals.

Aim: To analyze mango fruit juice samples for their nutritional value.  Mango fruit is perishable in nature and cannot be stored for long time. It can be made available during off season, by processing in to juices, jams, squashes, nectars, chutney, pickles, toffees and canned mango slices etc.

Study Design: Different physico chemical and elemental parameters were studied for four different made tetra packed mango juice samples available in local market.

Place and Duration of Study: Department of Applied Sciences, Chemistry section, University of Technology and Applied Sciences, Muscat, Oman. The study was performed during the January 2016 – July 2016.

Methodology: Different parameters were studied such as pH, conductivity, acidity, ash content, vitamin C, moisture and some mineral contents. Some chemical and instrumental methods were used for analysis.  

Results: pH was found to be in the range of 3.17 – 3.97, conductivity 0.941 – 1.053 MS/cm, sugar found in the range of 13 – 15 ⁰brix, density was found 0.939 – 1.015 g/cm³, water 65.25 – 67%, ash was found to be in the range of 0.059 – 0.099%, total acidity found 0.173 – 0.275 %. Vitamin C was found in the range of 24.8 – 67.3 mg/100 ml, potassium 6.6 – 94, sodium 6 – 69 mg/100 ml, calcium 0 – 105 mg/100 ml and iron was found to be in the range of 1.375 – 2.145 mg/100 ml.

Conclusion: Based upon result obtained found that content of all selected samples were contains labelled nutrients. Sample STMJ was having remarkable good amount of Vitamin C while sample ARMJ found good amount of potassium and iron content.  In acidic perspective sample PMJ was higher acidic and ARMJ sample less acidic in nature.

This study investigated the potential of some agricultural wastes viz; African Star apple seed shell (ASS, plant source), crab shell (CS, animal source) and chicken egg shell (ES, animal source) as eco-friendly and low-cost biological materials for the removal of heavy metals from poultry wastewater. TS, TSS and TDS of the wastewater sample were assayed by filtration methods, chloride content by previously reported method and heavy metal contents (Zn, V, Cd, Fe, Ni, Cu, Co, Pb, Cr and Mn); were analyzed using Microwave Plasma Atomic Emission Spectrometer. The results of the solids and chloride contents of the poultry wastewater were TDS (3100 mg/L), TS (3700 mg/L), TSS (6000 mg/L) and chloride (4.7 g/L); all above the EPA permissible limits. Results of the FTIR analysis showed that ASS is an amide polymer while the CS and ES shells are mixtures of amide and carbonate polymers. Also, results of heavy metal analysis before and after adsorption showed that ASS caused removal of Zn, V, Fe, Cu, Co/ Pb and Mn by 48.27, 32.22, 49.64, 91.44, 100 and 82.39% respectively while Cd, Ni and Cr contents increased by 31, 61 and 48.3% respectively. CS showed removal of Fe, Ni/ Co/ Cr, Pb and Mn by 89.64, 100, 3.51 and 95.96% respectively while Zn, V, Cd and Cu contents increased by 1.7, 61.2, 76.1 and 68.1% respectively. Meanwhile, with ES, the contents of Zn, Fe, Ni, Cu, Cr and Mn increased by 31.56, 86.36, 100, 55.5, 45.80 and 90.33% respectively while the contents of V, Cd, Co and Pb decreased by 78.9, 86.7, 42.5 and 46.2% respectively. This study demonstrated the use of ASS, CS and ES as low- cost and eco-friendly agricultural wastes with significant potential for removal of heavy metals from wastewaters.

Aims: Evaluate possible application of African Star Apple seed oil as industrial raw material geared towards possible conversion of waste to wealth with no negative impact as it borders on food scarcity. Also unveiling the possibility of a sustainable environment via the eradication of waste from the environment, thereby creating a clean environment.

Place and Duration of Study: Fresh ripped fruits of African Star Apple were bought from some local market sellers at Agbarha-Otor market which is located in Ughelli North Local Government Area of Delta State, Nigeria on longitude 6° 2' 54" E /5° 30' 40" N, between November, 2019 and March, 2020.

Experimental Details: Soxhlet extraction with n-hexane as solvent was used for the oil extraction of 100 g per batch of extraction. Pretreatment procedure of oil was done prior to transesterification. Homogenous base-catalyzed transesterification reaction was used in this study under controlled experimental conditions such as temperature, reaction time, methanol to oil molar ratio and catalyst type and concentration were examined under varied ranges to ascertain optimum experimental conditions for the reaction. Extracted seeds oil were analysed for its physicochemical properties using standard methods via: specific gravity, acid value, refractive index, saponification value, iodine value and free fatty acid using standard methods.

Results: The results showed an oil yield of 14.9%, an indication that the seed reflects a poor source of abundant oil. Results obtained for the physiochemical properties, revealed that; specific gravity, refractive index, saponification value, acid value, free fatty acid and iodine value showed values of 0.896 kg/m³, 1.549, 231.32 mgKOH/g, 3.23 mgKOH/g, 2.07% and 47.63 mg/100 g respectively. Also, results for Methanol: Oil ratio showed that maximum yield was obtained at 6:1 molar ratio. Maximum conversion efficiency for molar concentration was achieved at 0.75% for both catalysts. While a reaction time of 125 min projected better yield.

Conclusion: The seed of African star fruit are discarded as waste, therefore its use as a source of oil for industrial feedstock and other domestic application, poses no challenge with regards to food security. Its non-drying potential based on its low iodine value, makes it suitable lubricating oil for industrial application. Similarly, potential application of the oil as feedstock for the production of biodiesel is justified on the basis of its low acid value. Conclusively, the seeds may not have sufficient oil volume potential to be used as edible (domestic) and industrial oil. Consequently upon its low yield, application for biofuel production in commercial scale becomes unrealistic.

Air pollution is reported to have reduced to a level that has not been recorded since the end of World War (II), and this is largely due to the global lockdown imposed to curb the spread of the novel Coronavirus disease (COVID-19) across the globe, hence the need for a review, interpretation and harmonisation of the available literature in this regard. Attempt is made from the available literature in elaborating the generality of the concepts of air pollution from the perspective of the global lockdown due to the COVID-19 pandemic. The synergy between the lockdown and decreased air pollution in relation to climate change, is explored. Various health and environmental consequences of air pollution and climate change are outlined. Major ailments and mortalities associated to air pollution are bound to decrease due to reduction in air pollution, and this is affirmed. We highlight some achievable control measures and techniques for tackling air pollutants in line with the principles of green chemistry for re-consideration under reviewed policies and guidelines by governments, stakeholders and policy-makers. Additionally, we propose some new remediation measures and policies that could be harnessed and deliberated upon by stakeholders and policy-makers to checkmate greenhouse gases emissions, improve air quality and minimise air pollution and climate change. We recommend how these measures could be adopted and implemented for improved health care. Data need to be collated post COVID-19 to ascertain the level of mortalities due to the consequence of air pollution and compare same with the mortality rate for COVID-19.