10 research outputs found
Memórias e saberes: a adoção de plantas alimentícias não convencionais (PANC) na cozinha tradicional Mineira / Memories and knowledge: the adoption of unconventional food plants (PANC) in traditional Minas cuisine
Este artigo faz a interface entre a Gastronomia e a Memória Afetiva das autoras, enfatizando o emprego de Plantas Alimentícias não Convencionais (PANC) nas tradições culinárias das famílias dessas pessoas. O objetivo deste estudo foi mostrar como essas tradições estão conectadas à alimentação passada de geração em geração, na qual há a valorização dos produtos cultivados e colhidos nos quintais e hortas. Trata-se de uma pesquisa exploratória de caráter qualitativo, cuja coleta de dados foi feita por meio de pesquisa de campo através de arquivos fotográficos e entrevista semiestruturada na qual mostrou que os entrevistados atuam como guardiões do saber-fazer dessa prática. Além disso, foi um momento de acolhida aos entrevistados devido ao isolamento social provocado pela SARS-Cov-2
Avaliação da capacidade de adsorção de vermiculita hidrofóbica em contato direto com óleo.
Com o aumento da necessidade de diminuir ao máximo qualquer tipo de poluição, inúmeras técnicas, métodos e materiais para a retenção de óleos são desenvolvidos. Entre os materiais podem se destacar minerais com a capacidade de adsorver compostos apolares. Nesse caso, especificamente, damos relevância à vermiculita hidrofobizada. Nesse trabalho, a vermiculita hidrofobizada e a vermiculita somente expandida de diferentes granulometrias e de diferentes origens foram testadas quanto à adsorção de um ácido graxo específico: ácido oléico.With the increasing need to maximally reduce any type of pollution, countless techniques, methods and materials for oil retention are being developed. Among the materials that stand out are minerals which have a capacity to adsorb non-polar composites. In this case study, relevance is specifically given to hydrofobized vermiculite. The hydrofobized vermiculite and the vermiculite, including different sized particles and different origins, were tested for their adsorption capacity of a fatty acid: specifically, oleic acid
Adsorption of heavy metal ion from aqueous single metal solution by chemically modified sugarcane bagasse.
This work describes the preparation of new chelating materials derived from sugarcane bagasse for adsorption of heavy metal ions in aqueous solution. The first part of this report deals with the chemical modification of sugarcane bagasse with succinic anhydride. The carboxylic acid functions introduced into the material were used to anchor polyamines, which resulted in two yet unpublished modified sugarcane bagasse materials. The obtained materials were characterized by elemental analysis and infrared spectroscopy (IR). The second part of this reports features the comparative evaluation of the adsorption capacity of the modified sugarcane bagasse materials for Cu2+, Cd2+, and Pb2+ ions in aqueous single metal solution by classical titration. Adsorption isotherms were studied by the Freundlich and Langmuir models
Oxidized Renewable Materials for the Removal of Cobalt(II) and Copper(II) from Aqueous Solution Using in Batch and Fixed-Bed Column Adsorption
Batch and continuous adsorption of Co2+ and Cu2+ from aqueous solutions by oxidized sugarcane bagasse (SBox) and oxidized cellulose (Cox) were investigated. The oxidation reaction of sugarcane bagasse and cellulose was made with a mixture of H3PO4‒NaNO2 to obtain SBox and Cox, with the introduction of high number of carboxylic acid functions, 4.5 and 4.8 mmol/g, respectively. The adsorption kinetics of Co2+ and Cu2+ on SBox and Cox were modeled using two models (pseudo-first-order and pseudo-second-order) and the rate-limiting step controlling the adsorption was evaluated by Boyd and intraparticle diffusion models. The Sips and Langmuir models better fitted the isotherms with values of maximum adsorption capacity Qmax of 0.68 and 0.37 mmol/g for Co2+ and 1.20 and 0.57 mmol/g for Cu2+ adsorption on Cox and SBox, respectively. The reuse of both spent adsorbents was evaluated. Adsorption of Cu2+ and Co2+ on SBox in continuous was evaluated using a 22 factorial design with spatial time and initial metal concentration as independent variables and Qmax and effective use of the bed as responses. The breakthrough curves were very well described by the Bohart–Adams original model and the Qmax values for Co2+ and Cu2+ were 0.22 and 0.55 mmol/g. SBox confirmed to be a promising biomaterial for application on a large scale
Synthesis and application of sugarcane bagasse cellulose mixed esters. Part I: Removal of Co2+ and Ni2+ from single spiked aqueous solutions in batch mode using sugarcane bagasse cellulose succinate phthalate
Sugarcane bagasse cellulose mixed ester succinate phthalate (SBSPh) was synthesized by a novel one-pot reaction method. The effects of temperature, time and mole fraction of succinic anhydride (χSA) on the responses weight gain (wg), number of carboxylic acid groups (nT,COOH), and adsorption capacity (q) of Co2+ and Ni2+ were evaluated by a 23 experimental design. The chemical structure of the material was elucidated by Fourier transform infrared, 13C Multiple Cross-Polarization solid-state NMR spectroscopy and 1H NMR relaxometry. The best SBSPh synthesis condition (100 °C, 11 h, χSA of 0.2) yielded a wg of 59.1%, nT,COOH of 3.41 mmol g−1, and values of qCo2+ and qNi2+ of 0.348 and 0.346 mmol g−1, respectively. The Sips model fitted better the equilibrium data, and the maximum adsorption capacities (pH 5.75 and 25 °C) estimated by this model were 0.62 and 0.53 mmol g−1 for Co2+ and Ni2+, respectively. The ΔadsH° values estimated by isothermal titration calorimetry were 8.43 and 7.79 kJ mol−1 for Co2+ and Ni2+, respectively. Desorption and re-adsorption efficiencies were evaluated by a 22 experimental design, which showed that SBSPh adsorbent can be recovered and reused without significant loss of adsorption capacity