Portable and sustainable activated carbon-based device for electro-assisted water purification

Granular activated carbon (GAC) has been widely introduced to advanced drinking water purification plants to remove organic matter and ammonium. Backwashing, which is the routine practice for GAC maintenance, is an important operational factor influencing the performance of GAC and its microbial biomass. In this study, the effects of backwashing on the ammonium removal potential of GAC were evaluated. In addition, abundances of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) on GAC were analyzed. GAC samples before and after backwashing were collected from a full-scale drinking water purification plant. Samplings were conducted before and after implementation of prechlorination of raw water. The results showed that the ammonium removal potential of the GAC increased by 12% after backwashing before prechlorination (p < 0.01). After implementing the prechlorination, the ammonium removal potential of the GAC decreased by 12% even after backwashing (p < 0.01). The AOA was predominant on the GAC in the two samplings. Regardless of prechlorination, the amounts of the AOA and the AOB remained at the same level before and after backwashing. Analysis of the backwashing water indicated that the amounts of the AOA and AOB washed out from the GAC were negligible (0.08%–0.26%) compared with their original amounts on the GAC. These results revealed the marginal role of backwashing on the biomass of ammonia oxidizers on GAC. However, the results also revealed that backwashing could have a negative impact on the ammonium removal potential of GAC during prechlorination.

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CARVÃO ATIVADO GRANULAR IMPREGNADO COM ZINCO PARA REMOÇÃO DE BACTÉRIAS DA ÁGUA PARA CONSUMO HUMANO

e-xacta ◽

10.18674/exacta.v6i2.1053 ◽

2013 ◽

Vol 6 (2) ◽

pp. 1

Author(s):

Flávia Sayuri Arakawa ◽

Quelen Letícia Shimabuku ◽

Priscila Ferri Coldebella ◽

Franciele Pereira Camacho ◽

Fernando Alves Silva ◽

...

Keyword(s):

Escherichia Coli ◽

Antibacterial Activity ◽

Drinking Water ◽

Activated Carbon ◽

Water Purification ◽

Granular Activated Carbon ◽

Filter Media ◽

Para Determinar ◽

Drinking Water Purification ◽

Filter Bed

O carvão ativado granular impregnado com zinco (C/Zn) foi avaliado em relação à atividade antibacteriana para eliminação de micro-organismos na purificação de água para consumo humano. Os meios filtrantes produzidos a partir de C/Zn foram caracterizados através de técnicas instrumentais como análises de BET e difração de raios-X (DRX) para determinar a distribuição de poros e área superficial e as fases estruturais, respectivamente. Experimentos foram realizados em um sistema doméstico de purificação de água utilizando filtros com leito de carvão ativado granular sem impregnação e com impregnação de zinco nas concentrações de 1,0, 3,0, 5,0 e 10,0% (m/m). A atividade antibacteriana dos meios filtrantes foi avaliada em relação à eficiência de remoção de bactérias Escherichia coli da água. Foram preparadas soluções sintéticas com água deionizada contaminada artificialmente com uma concentração aproximada entre 1,0x105 a 9,0x106 UFC/100mL de Escherichia coli. Assim a eficiência bacteriológica dos meios filtrantes com C/Zn foi superior com o aumento da concentração de zinco impregnado no carvão ativado. O filtro com leito de carvão ativado impregnado com 10% de zinco apresentou a maior eficiência com remoção de Escherichia coli superior a 99% e melhorando a qualidade bacteriológica da água para consumo humano.AbstractGranular activated carbon impregnated with zinc (C/Zn) was evaluated for the antibacterial activity for elimination of micro-organisms in drinking water purification. The filter media produced from C/Zn were characterized by instrumental techniques such as the BET analyzes and x-ray diffraction (XRD) to determine the pore distribution and surface area and structural phases, respectively. Experiments were performed in a household water purification system using filters with granular activated carbon bed without impregnation and impregnation with zinc in concentrations of 1.0, 3.0, 5.0 and 10.0% (w/w). The antibacterial activity of the filter media was evaluated regarding to the removal efficiency of bacteria Escherichia coli of water. Synthetic solutions were prepared with deionized water contaminated artificially with an approximate concentration of 1.0 x105 to 9.0 x106 CFU/100mL of Escherichia coli. The efficiency bacteriological efficiency bacteriological of filter media with C/Zn was higher with increasing concentration of zinc impregnated on activated carbon.The filter bed of activated carbon impregnated with 10% of zinc showed the highest efficiency with removal of bacterial Escherichia coli higher than 98% and improving the bacteriological quality of drinking water.

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Carbon-Based Materials from Borassus flabellifer and their Applications

Journal of Environmental Nanotechnology ◽

10.13074/jent.2021.12.214445 ◽

2021 ◽

Vol 10 (4) ◽

pp. 08-12

Author(s):

C. Thevamirtha ◽

Sherin Monichan ◽

P. Mosae Selvakumar

Keyword(s):

Sustainable Development ◽

Activated Carbon ◽

Water Purification ◽

Anode Materials ◽

Carbon Materials ◽

Low Cost ◽

Carbon Nanodots ◽

Hard Carbon ◽

High Demand ◽

Carbon Based

Plant-based carbon materials are a high-demand source nowadays, as they are low-cost, eco-friendly, easily available, and sustainable. Borassus flabellifer (Palmyra palm) is a gift of nature that gives numerous benefits, as all parts of the tree can be used for multiple purposes. Palmyraculture is the practice of cultivating Palmyra palms and utilizing them to live a self-reliant life in working towards sustainable development. Due to the advancement of technology, Borassus flabellifer is used to synthesize carbon materials, including hard carbon, carbon nanodots, charcoal, and activated carbon. These carbon materials can be used in electrochemistry as anode materials, biosensing, bioimaging, catalysts, and water purification. This review mainly focuses on the carbon materials derived from the Borassus flabellifer, their applications in various fields, and further aspects that have to be considered.

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