Environmental Friendly Natural Polymer and Its Polylactic Acid Modified Composite Synthesized from Thais Coronata Shell for Urea Uptake from Waste Water by Equilibration
Okolie Davidson,
Adowei Pereware,
Charles Ikenna Osu
Issue:
Volume 8, Issue 1, March 2023
Pages:
1-8
Received:
27 March 2023
Accepted:
20 April 2023
Published:
10 May 2023
Abstract: CHITOSAN was extracted from Thais Coronata shell and modified with poly-lactic acid by gelation method to derive its poly-lactic chitosan nano-composite. Both the chitosan and the polylactic acid modified composite where analyzed using FT-IR and SEM for changes in functional group and surface morphology. A spectrum of unmodified chitosan with absorption bands ranging from 3533 cm-1 to 3942 cm-1, all attributed to O-H stretching vibrations, and a cluster of bands attributed to N-H stretching vibrations of primary and secondary amine at 3417 cm-1, 3317 cm-1, 3286 cm-1, and 3217cm-1. The -NH2 stretching is approximated matched by the high and deep adsorption peak at 1496cm-1 corresponding to Amide II, which is a characteristic band of N-acetylation. SEM images of unmodified and poly-lactic acid modified chitosan composites at 500 and 1500x magnification reveals a rough surface with significant pores, typified and notable irregularities that are ideal for adsorption. The morphology of the poly-lactic acid modified chitosan has changed significantly in relation to its weak surface properties, with a smoother surface domain and reduced pore structure. The degree of ionic activity between chitosan and the poly lactic acid grafted onto the polymer chain is linked to morphological variability. The samples where investigated as potential bio-sorbents for urea uptake from waste water by equilibration. Adsorption experiments were conducted on 20100mg/L urea wastewater and the effect of contact time, concentration, temperature and pH on urea removal efficiency was studied. At temperature of 30°C and pH of 2.5, maximum removal efficiency of 50.16 and 54.33% were obtained for the modified and un-modified chitosan respectively. Results from adsorption studies revealed that the modification with poly-lactic acid did not enhance adsorption capacity of chitosan, although its solubility and resistance to acidic degradation was improved. The development of chitosan materials with better adsorption capacity in the light of urea uptake is therefore very feasible.
Abstract: CHITOSAN was extracted from Thais Coronata shell and modified with poly-lactic acid by gelation method to derive its poly-lactic chitosan nano-composite. Both the chitosan and the polylactic acid modified composite where analyzed using FT-IR and SEM for changes in functional group and surface morphology. A spectrum of unmodified chitosan with absor...
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Toxicological Effects of Thiamethoxam on Non-Target Aquatic Organisms
Mohammad Mosleh Uddin,
Shayla Sultana Mely,
Al Faruk
Issue:
Volume 8, Issue 1, March 2023
Pages:
9-12
Received:
2 April 2023
Accepted:
19 May 2023
Published:
6 June 2023
Abstract: Thiamethoxam (THM), a neonicotinoid insecticide, has garnered significant attention due to its prevalence in agriculture and potential toxicity to aquatic organisms. This study aims to summarize the toxicological effects of THM on non-target aquatic organisms. Insecticide THM enters aquatic ecosystems through various routes, including runoff from treated fields, drifting from sprayed areas, and leaching into groundwater. The impact of THM on various species of fish, crustaceans, and aquatic insects has been extensively studied, yielding disparate results regarding its toxicity. The toxicity of THM is contingent upon various factors, including the species and developmental stage of the organism and the conditions of exposure. Despite this variability, several studies have indicated that certain species of fish and crustaceans are highly susceptible to the toxic effects of THM. In addition to the acute toxicity of THM, its chronic effects have also been a source of concern. Chronic exposure to low levels of insecticide has been demonstrated to result in many deleterious effects, including growth inhibition, altered behavior, and decreased reproductive success. Given the potential toxicity of THM to aquatic organisms, it is imperative to undertake a comprehensive risk assessment to minimize its release into the aquatic environment. Further research is needed to better understand the full extent of the toxicological effects of THM on non-target aquatic organisms and to develop effective mitigation strategies.
Abstract: Thiamethoxam (THM), a neonicotinoid insecticide, has garnered significant attention due to its prevalence in agriculture and potential toxicity to aquatic organisms. This study aims to summarize the toxicological effects of THM on non-target aquatic organisms. Insecticide THM enters aquatic ecosystems through various routes, including runoff from t...
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