RESUMEN
Phosphorus (P) concentration beyond threshold limit can trigger eutrophication in stagnant water bodies nevertheless it is an indispensable macronutrient for aquatic life. Even in low P concentration (≤1 mg L-1), P can be detrimental for ecosystem's health, but this aspect has not been thoroughly investigated. The elimination of low P content is rather expensive or complex. Therefore, a unique and sustainable approach has been proposed in which valorized bivalve seashells can be used for the removal of low P content. Initially, acicular shaped aragonite particles (~21 µm) with an aspect ratio of around 21 have been synthesized through the wet carbonation process and used to treat aqueous solutions containing P in low concentration (P ≤ 1 mg L-1). Response surface methodology based Box-Behnken design has been employed for optimization study which revealed that with aragonite dosage (140 mg), equilibrium pH (~10.15), and temperature (45 °C), a phosphorus removal efficiency of ~97% can be obtained in 10 h. The kinetics and isotherm studies have also been carried out (within the range P ≤ 1 mg L-1) to investigate a probable removal mechanism. Also, aragonite demonstrates higher selectivity (>70%) towards phosphate with coexisting anions such as nitrate, chloride, sulfate, and carbonate. Through experimental data, elemental mapping, and molecular dynamic simulation, it has been observed that the removal mechanism involved a combination of electrostatic adsorption of Ca2+ ions on aragonite surface and chemical interaction between the calcium and phosphate ions. The present work demonstrates a sustainable and propitious potential of seashell derived aragonite for the removal of low P content in aqueous solution along with its unconventional mechanistic approach.
Asunto(s)
Carbonato de Calcio , Contaminantes Químicos del Agua , Adsorción , Exoesqueleto , Animales , Ecosistema , Concentración de Iones de Hidrógeno , Cinética , Fosfatos , Fósforo , AguaRESUMEN
For decades, researchers have debated whether climate change has an adverse impact on diseases, especially infectious diseases. They have identified a strong relationship between climate variables and vector's growth, mortality rate, reproduction, and spatiotemporal distribution. Epidemiological data further indicates the emergence and re-emergence of infectious diseases post every single extreme weather event. Based on studies conducted mostly between 1990-2018, three aspects that resemble the impact of climate change impact on diseases are: (a) emergence and re-emergence of vector-borne diseases, (b) impact of extreme weather events, and (c) social upliftment with education and adaptation. This review mainly examines and discusses the impact of climate change based on scientific evidences in published literature. Humans are highly vulnerable to diseases and other post-catastrophic effects of extreme events, as evidenced in literature. It is high time that human beings understand the adverse impacts of climate change and take proper and sustainable control measures. There is also the important requirement for allocation of effective technologies, maintenance of healthy lifestyles, and public education.