47 research outputs found
Environmental health and inequalities : building indicators for sustainable development
O Brasil, mesmo com os avanços nos indicadores socioeconĂŽmicos ainda se apresenta desigual, situação fruto de um desenvolvimento historicamente excludente. Foi escolhido o Ăndice de Desenvolvimento Humano (IDH) e indicadores sociais, econĂŽmicos, ambientais e de saĂșde para exemplificar essa problemĂĄtica. Foram selecionados os municĂpios que apresentavam mais baixos IDHs no ano de 2000 e comparada sua evolução temporal entre 2000 e 2010 por meio de indicadores relacionados aos pilares econĂŽmico, ambiental e social do desenvolvimento sustentĂĄvel. Estes possuem um IDH classificado como baixo (<0.500) e correspondem a paĂses como Laos, IĂȘmen, Haiti e Madagascar. No Ăąmbito nacional, verificou-se, entre o inĂcio dos anos 2000 e o fim dessa dĂ©cada, uma importante melhora do indicador do pilar econĂŽmico (diminuição de 23,9% para 8,9% de pessoas vivendo com menos de 1/4 de salĂĄrio mĂnimo), sendo que os indicadores referentes aos pilares social (aumento de 86,5% para 90,2% de mulheres alfabetizadas) e ambiental (aumento de 81% para 85% no acesso a rede geral de ĂĄgua), tambĂ©m apresentaram melhoria, embora em menor grau. Concluiu-se que para alcançar o desenvolvimento sustentĂĄvel e com qualidade de vida, a melhora dos indicadores de saneamento e de educação deve ser uma prioridade para o Brasil. _______________________________________________________________________________________ ABSTRACTDespite its progress in terms of socioeconomic indicators, Brazil is still unequal, which is due to an unequal and exclusionary historical process. In this paper we selected the Human Development Index â HDI and other social, economic, environmental and health indicators to exemplify this situation. We selected the municipalities that had the lowest HDI in the country in 2000 comparing their evolution over time between 2000 and 2010 by means of indicators linked to the economic, environmental and social pillars of sustainable development. These municipalities have an HDI classified as low (<0.500), and correspond to countries such as Laos, Yemen, Haiti and Madagascar. At national level, data for the decade show a significant improvement in economic indicators (decrease from 23% to 8.9% of people living on less than a quarter of the minimum wage); social indicators (increase from 86.5% to 90.2% of literacy in women), and the environmental indicator associated with access to the water grid, which also improved to a lesser extent (increase from 81% to 85%). It was concluded that in order to achieve sustainable development with quality of life, the improvement of sanitation and education indicators should be a priority for Brazil
Treatment of water containing methylene by biosorption using Brazilian berry seeds (Eugenia uniflora)
Brazilian berry seeds (Eugenia uniflora) were used as an eco-friendly and low-cost biosorbent for the treatment of textile effluents containing methylene blue. Characterization techniques indicated that Brazilian berry seeds are constituted of irregular particles, mainly composed of lignin and holocellulose groups, distributed in an amorphous structure. Methylene blue biosorption was favorable at pH of 8, using a biosorbent dosage of 0.8 g Lâ1. The equilibrium was reached in the first 20 min for lower M methylene blue concentrations and 120 min for higher methylene blue concentrations. Furthermore, the general and pseudo-second-order models were suitable for describing the kinetic data. Langmuir was the most adequate model for describing the isotherm curves, predicting a biosorption capacity of 189.6 mg gâ1 at 328 K. Biosorption was spontaneous (ââ9.54ââ€âÎG0 â€ââ8.06 kJ molâ1) and endothermic, with standard enthalpy change of 6.11 kJ molâ1. Brazilian berry seeds were successfully used to remove the color of two different simulated textile effluents, achieving 92.2% and 73.5% of removal. Last, the fixed-bed experiment showed that a column packed with Brazilian berry seeds can operate during 840 min, attaining biosorption capacity of 88.7 mg gâ1. The data here presented indicates that textile effluents containing methylene blue can be easily and successfully treated by an eco-friendly and low-cost biosorbent like Brazilian berry seeds
Evaluation of Ocotea puberula bark powder (OPBP) as an effective adsorbent to uptake crystal violet from colored effluents: alternative kinetic approaches
The Ocotea puberula bark powder (OPBP) was evaluated as an effective adsorbent for the removal of crystal violet (CV) from colored effluents. OPBP was characterized and presented a surface with large cavities, organized as a honeycomb. The main functional groups of OPBP were O-H, N-H, C=O, and C-O-C. The adsorption of CV on OPBP was favorable at pH 9 with a dosage of 0.75 g Lâ1. The Avrami model was the most suitable to represent the adsorption kinetic profile, being the estimated equilibrium concentration value of 3.37 mg Lâ1 for an initial concentration of 50 mg Lâ1 (CV removal of 93.3%). The equilibrium was reached within 90 min. The data were better described by the Langmuir isotherm, reaching a maximum adsorption capacity of 444.34 mg gâ1 at 328 K. The Gibbs free energy ranged from ââ26.3554 to ââ27.8055 kJ molâ1, and the enthalpy variation was ââ11.1519 kJ molâ1. The external mass transfer was the rate-limiting step, with Biot numbers ranging from 0.0011 to 0.25. Lastly, OPBP application for the treatment of two different simulated effluents was effective, achieving a removal percentage of 90%
Transforming shrub waste into a high-efficiency adsorbent: Application of Physalis peruvian chalice treated with strong acid to remove the 2,4-dichlorophenoxyacetic acid herbicide
In this study, the chalice generated from the production of the Physalis peruviana fruit was subjected to a treatment with sulfuric acid and applied in the adsorption of 2,4-Dichlorophenoxyacetic acid (2,4-D). The precursor, and the treated material before and after the adsorption, were analyzed by different techniques. After the acid treatment, it was found that the surface was changed from a smooth to an irregular surface with the presence of cavities with irregular size. The adsorption was favored at pH = 2 and with a dosage of 0.8 g Lâ1. The pseudo-second-order model was the best to represent kinetic data. The isothermal experiments were well represented by the Langmuir and TĂłth models, reaching a high capacity of 244 and 320 mg gâ1, respectively. The computed thermodynamic values show that the 2,4-D adsorption was spontaneous and exothermic. Overall, this study indicates that the Physalis peruviana chalice treated with strong acid presents great potential as an alternative material for the adsorption/removal of 2,4-D herbicide from liquid effluents
An eco-friendly and low-cost strategy for groundwater defluorination: adsorption of fluoride onto calcinated sludge
The excess of fluoride ions (Fâ) in water for human supply is a serious public health. The recommended concentration of Fâ ions by the World Health Organization (WHO) is 1.5âmgâL-1. Several groundwater sources around the world contain high Fâ concentrations, and require treatment before human consumption. It was developed an eco-friendly and low-cost strategy for groundwater defluorination, i.e., adsorption onto calcinated sludge. This strategy was efficient at pH of 5.5 and using 5âg L-1 of calcinated sludge. The groundwater attained the WHO standard within 60âmin. The kinetic model of pseudo-second-order obtained a better adjustment to the experimental data. The equilibrium curve at 25â°C was better represented by the TĂłth model. The maximum adsorption capacity was 2.04âmgâg-1. Therefore, adsorption using calcinated sludge can be considered as an eco-friendly and low-cost strategy for groundwater defluorination
Highly effective adsorption of synthetic phenol effluent by a novel activated carbon prepared from fruit wastes of the Ceiba speciosa forest species
Fruit wastes of the Ceiba speciosa forest species were employed as raw material for preparing activated carbon towards removing phenol from water. Concave cavities spread over the entire material surface were observed from characterization results, resulting in a high surface area, 842 m2 gâ1. Adsorption isotherm and kinetic studies were performed under the best conditions of pH (7) and adsorbent dosage (0.83 g Lâ1). An increase in temperature from 298 K to 328 K disfavored the phenol adsorption, decreasing from 156.7 to 145 mg gâ1 for the best-fit model, Langmuir. The thermodynamic results indicated that the phenol adsorption was spontaneous, favorable, and exothermic. The phenol concentration decay shows that the equilibrium is reached at 120 min. The pore volume and surface diffusion model (PVSDM) was employed satisfactorily to describe the phenol decay behavior. The surface diffusion coefficient values were in the range of 10â9 cm2 sâ1. The external and the internal mass transfer were the rate-controlling mechanisms. Therefore, the application of fruit wastes from Ceiba speciosa as raw material for preparing activated carbon proved very efficient towards removing phenol from an aqueous medium. The activated carbon is an alternative material to suppress water contamination due to phenol-derived species
High-performance removal of 2,4-dichlorophenoxyacetic acid herbicide in water using activated carbon derived from Queen palm fruit endocarp (Syagrus romanzoffiana)
In this work, an activated carbon sample with a high adsorptive performance for the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was prepared from queen palm endocarp (Syagrus romanzoffiana) by pyrolysis process. The activated carbon presented an XRD pattern related to carbon graphite and functional groups such as CâH, CËO, OâH. The material particles presented a highly-porous structure, being beneficial to the adsorption process. The activated carbon showed a remarkable specific surface area of 782 m2 gâ1 and pore volume of 0.441 cm3 gâ1. The solution pH presented a strong influence on the adsorption process, with ideal pH = 2, being the best adsorbent dosage, 0.5 g Lâ1. The correspondent removal percentage was 95.4%. The pseudo-second-order model represented kinetic data, presenting R2 > 0.992 and MSR 0.997) and lowest values of MSR (< 92.04 (mg gâ1)2), indicating a maximum capacity of 367.77 mg gâ1. The thermodynamic study indicated a spontaneous operation, with ÎG0 ranging from â23.2 to â32.6 kJ molâ1 and endothermic process (ÎH0 = 67.30 kJ molâ1), involving physical interactions in the adsorbent/adsorbate system. The adsorbent could be regenerated by NaOH and used 7 times with the same adsorption capacity. Hence, overall, the activated carbon prepared from the JerivĂĄ endocarp corresponds to a promising adsorbent in removing 2,4-D herbicide in wastewater
Utilization of Pacara Earpod tree (Enterolobium contortisilquum) and Ironwood (Caesalpinia leiostachya) seeds as low-cost biosorbents for removal of basic fuchsin
Wastes from the Pacara Earpod tree (Enterolobium contortisilquum) and Ironwood (Caesalpinia leiostachya) seeds were studied as biosorbents for the removal of basic fuchsin from waters. Both biosorbents were prepared and characterized by different analytical methods. The characterization data showed that both materials were mainly composed of lignin, cellulose, and hemicellulose. Both biosorbents exhibited roughened surfaces and surface functional groups such as C-H, C=O, C=C, C-O, C-N, and OH bonds. Furthermore, the XRD pattern shows an amorphous phase with a wide peak from 10 to 30° due to the lignin. In terms of dosage and pH, the use of 1 g Lâ1 and 9.0, respectively, is recommended. The initial concentrations for the biosorption kinetics ranged from 50 to 500 mg Lâ1, where the Pacara ear and the Ironwood reached an adsorption capacity of 145.62 and 100.743 mg gâ1 for the 500 mg Lâ1. The pseudo-second-order was found to be the proper model for describing biosorption of basic fuchsin onto Pacara Earpod tree and Ironwood, respectively. For the isotherm experiments, the maximum experimental biosorption capacity was found to be 166.858 and 110.317 mg gâ1 for the Pacara Earpod and Ironwood for the initial concentration of 500 mg Lâ1 at 328 K. The Langmuir and the TĂłth models were the best for representing the equilibrium curves for the basic fuchsin on the Pacara Earpod and the Ironwood, respectively. Maximum adsorption capacities of 177.084 mg gâ1 and 136.526 mg gâ1 were achieved for the Pacara Earpod tree and Ironwood, respectively. The biosorption process was spontaneous, endothermic, and favorable for both biosorbents. The biosorbents were also applied for coloration removal of simulated textile effluents, reaching 66% and 54% for the Pacara Earpod and Ironwood, respectively. For the final application, the materials were used in fixed-bed biosorption, with an initial concentration of 200 mg Lâ1, reaching breakthrough times of 710 and 415 min, leading to biosorption capacities of the column of 124.5 and 76.5 mg gâ1, for the Pacara Earpod and Ironwood, respectively
Development of highly porous activated carbon from Jacaranda mimosifolia seed pods for remarkable removal of aqueous-phase ketoprofen
In this work, a high porous activated carbon from Jacaranda mimosifolia was developed and employed for ketoprofen adsorption. After the pyrolysis process at 973.15 K, the material presented cavities with different sizes allocated on the particle surface. The material presented a pH at the point of zero charge of 4.1 with the best adsorption at pH 2. The best adsorbent dosage was 0.72 g Lâ1, corresponding to a removal of 96%. The system reached the adsorption equilibrium after 120 min and was described by the linear driving force model. The isotherms revealed that the adsorption capacity decreased with the temperature and followed the Langmuir model, with a maximum adsorption capacity of 303.9 mg gâ1. This high capacity can be associated with the high surface area (928 m2 gâ1) and pore volume (0.521 cm3 gâ1) values. The thermodynamic values indicated that the adsorption system is spontaneous and exothermic. The enthalpy value indicates that the interactions between the adsorbent and adsorbate are physical. Regeneration tests showed a decreasing percentage of removal of 7.86% after 5 cycles. Finally, the adsorbent showed efficiency when treating a simulated effluent containing drugs and inorganic salts, showing the removal of 71.43%