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1.
Chemosphere ; 356: 141932, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593955

RESUMO

The presence of heavy metals in water pose a serious threat to both public and environmental health. However, the advances in the application of low cost biochar based adsorbent synthesize from various feedstocks plays an effective role in the of removal heavy metals from water. This study implies the introduction of novel method of converting food waste (FW) to biochar through pyrolysis, examine its physiochemical characteristics, and investigate its adsorption potential for the removal of heavy metals from water. The results revealed that biochar yield decreased from 18.4 % to 14.31 % with increase in pyrolysis temperature from 350 to 550 °C. Likewise, increase in the pyrolysis temperature also resulted in the increase in the ash content from 39.87 % to 42.05 % thus transforming the biochar into alkaline nature (pH 10.17). The structural and chemical compositions of biochar produced at various temperatures (350, 450, and 550 °C) showed a wide range of mineralogical composition, and changes in the concentration of surface functional groups. Similarly, the adsorption potential showed that all the produced biochar effectively removed the selected heavy metals from wastewater. However a slightly high removal capacity was observed for biochar produced at 550 °C that was credited to the alkaline nature, negatively charged biochar active sites due to O-containing functional groups and swelling behavior. The results also showed that the maximum adsorption was recorded at pH 8 at adsorbent dose of 2.5 g L-1 with the contact time of 120 min. To express the adsorption equilibrium, the results were subjected to Langmuir and Freundlich isotherms and correlation coefficient implies that the adsorption process follows the Freundlich adsorption isotherm. The findings of this study suggest the suitability of the novel FW derived biochar as an effective and low cost adsorbent for the removal of heavy metals form wastewater.


Assuntos
Carvão Vegetal , Metais Pesados , Águas Residuárias , Poluentes Químicos da Água , Carvão Vegetal/química , Metais Pesados/química , Metais Pesados/isolamento & purificação , Águas Residuárias/química , Adsorção , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Pirólise , Alimentos , Perda e Desperdício de Alimentos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38012495

RESUMO

Municipal solid waste (MSW) management poses a significant environmental challenge in municipalities across developing nations worldwide. Our studies were focused on characterizing the waste and analyzing the chemical properties of mixed waste fractions to assess their potential for waste-to-energy conversion. The objective of our study was to scrutinize the existing state of the MSW management system and gauge its waste generation rates. Specific ASTM methods were employed to carry out both physical and chemical characterizations. The outcomes reveal that the city generates a daily volume of 1155 tons of domestic solid waste (DSW), translating to a generation rate of 0.51 kg-1 capita-1 day-1. When analyzed by source, organic matter emerged as the predominant constituent, accounting for 73.74% of the waste, followed by combustible content waste at 15.17%. The moisture content of MSW ranged between 26 and 58% throughout the seasons, while volatile solids varied from 22.35 to 99.74%. Among the components screened, carbon and oxygen stood out as the dominant elements. The calorific values encompassed a broad range, ranging from 14.87 MJ kg-1 for leather waste to a substantial 25,629.27 MJ kg-1 for organic waste. To alleviate the escalating burden of increasing solid waste generation, alternative treatment approaches were recommended. These include composting, biomethane plants, the establishment of recycling facilities, and the enhancement of existing landfill sites to scientifically designed landfills. In summary, the findings from this study provide valuable insights for regulatory bodies and municipal authorities. These insights can guide the formulation of policies concerning waste sampling, characterization, segregation, and the implementation of education and awareness campaigns.

3.
Environ Res ; 215(Pt 2): 114240, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36103930

RESUMO

Biomedical waste from healthcare activities poses a higher hazard of infection and damage than other types of trash. The main objective of the study was to assess the awareness knowledge and practices of biomedical waste management (BMWM) among health care professionals in the health care units. The cross-sectional study was carried out to access the awareness, knowledge and practices of health care professionals for BMWM. Using a qualitative approach, the study was escorted in two Apex hospitals i.e. the Allied Hospital and the District Head Quarter Hospital, Faisalabad, Pakistan from August 5, 2019 to October 15, 2019. More than 90% of respondents knew the phrase BMWM, but just 35.4% had awareness about biomedical waste regulations. About 71.6% of the respondents were familiar with biomedical waste's color-coding segregation. The study concludes gap in the awareness, knowledge and practices for BMWM. The sanitary workers of the hospitals had no knowledge about BMWM and the BMWM/healthcare waste management rule 2005 established in Pakistan due to the lack of training regarding waste management and the segregation process. Some of the staff members were aware of the BMWM practices under the rules and regulations of Pakistan but were unable to implement at their work place. It is necessary to dispose of the biomedical waste according to the established terms and conditions of BMWM rules (2005) of Pakistan. Weak structure of BMWM was observed at the study sites due to the lack of training, liabilities and absence of penalties against improper biomedical waste disposal as violation of the rules and regulations. It's a dire need of the time to consider the biomedical waste as hazardous waste and make policies for its safe disposal and ensure the implementation of the policies in all the medical centers of Pakistan.


Assuntos
Doenças Transmissíveis , Eliminação de Resíduos de Serviços de Saúde , Gerenciamento de Resíduos , Estudos Transversais , Resíduos Perigosos , Pessoal de Saúde , Hospitais , Humanos
4.
Environ Monit Assess ; 188(5): 267, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27048492

RESUMO

Gaseous pollutant emissions from brick kiln industries deteriorate the current state of ambient air quality in Pakistan and worldwide. These gaseous pollutants affect the health of plants and may decrease plant growth and yield. A field experiment that was conducted to monitor the concentration of gaseous pollutants emitted mainly from brick kilns in the ambient air and associated impacts on the growth and physiological attributes of the two wheat (Triticum spp.) cultivars. Plants were grown at three sites, including control (Ayub Agriculture Research Institute, AARI), low pollution (LP) site (Small Estate Industry), and high pollution (HP) site (Sidar Bypass), of Faisalabad, Pakistan. Monitoring of ambient air pollution at experimental sites was carried out using the state-of-art ambient air analyzers. Plants were harvested after 120 days of germination and were analyzed for different growth attributes. Results showed that the hourly average concentration of gaseous air pollutants CO, NO2, SO2, and PM10 at HP site were significantly higher than the LP and control sites. Similarly, gaseous pollutants decreased plant height, straw and grain yield, photosynthesis and increased physical injury, and metal concentrations in the grains. However, wheat response toward gaseous pollutants did not differ between cultivars (Galaxy and 8173) studied. Overall, the results indicated that brick kiln emissions could reduce the performance of wheat grown in the soils around kilns and confirm the adverse impacts of pollutants on the growth, yield, and quality of the wheat.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Materiais de Construção , Monitoramento Ambiental , Fotossíntese/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Triticum/efeitos dos fármacos , Agricultura , Poluição do Ar/análise , Gases , Indústrias , Metais , Paquistão , Triticum/crescimento & desenvolvimento
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