Search results for "Biosorption"
showing 10 items of 31 documents
Highlighting inconsistencies regarding metal biosorption.
2015
Thousands of articles have been devoted to examine different types of biosorbents and their use in cleaning polluted waters. An important objective of some studies has been the identification of the biosorption mechanisms. This type of investigation is not always performed, as it can only be done if scientists are aware of all mechanisms that, at least theoretically, control the removal of the target substances. Mistakes are often made, even in highly cited review articles, where biosorption mechanisms are named and/or grouped. The aim of this article is to highlight errors and inaccuracies as well as to discuss different classification systems of the biosorption mechanisms. This article se…
Metals in aqueous solutions and real effluents: biosorption behavior of a hemp-based felt
2018
In this study, a hemp-based material in the form of a felt is used to adsorb metals in individual aqueous solutions and in polycontaminated effluents using the batch method. The factors affecting the biosorption process were initial metal concentration, biosorbent dosage, contact time and pH. In controlled conditions, results showed that: (i) the felt exhibited high adsorption capacities towards metals in the following order: Pb g (ii) no significant differences were observed for the three salts used (sulfate, chloride and nitrate); (iii) the process was rapid: 10 min were sufficient to attain equilibrium ; iv) the biosorption efficiency increased considerably with the increase of the bioso…
Biotransformation and toxicity effect of monoanthraquinone dyes during Bjerkandera adusta CCBAS 930 cultures.
2020
Abstract The aim of this study was to evaluate of possibility of biotransformation and toxicity effect of monoanthraquinone dyes in cultures of Bjerkandera adusta CCBAS 930. Phenolic compounds, free radicals, phytotoxicity (Lepidium sativum L.), ecotoxicity (Vibrio fischeri) and cytotoxicity effect were evaluated to determine the toxicity of anthraquinone dyes before and after the treatment with B. adusta CCBAS 930. More than 80% of ABBB and AB129 was removed by biodegradation (decolorization) and biosorption, but biodegradation using oxidoreductases was the main dye removing mechanism. Secondary products toxic to plants and bacteria were formed in B. adusta strain CCBAS 930 cultures, despi…
Biosorption of copper by wine-relevant lactobacilli
2011
Must and wine may be contaminated with elevated copper concentrations by the use of fungicides or in course of the vinification process. Hitherto only a few practicable and harmless procedures exist to reduce an excess of copper from must and wine. For this reason we investigated the biosorption of copper by eight wine-relevant Lactobacillus species. Both, living and heat-inactivated cells revealed a significant degree of Cu adsorption. It was shown that Cu binding correlated positively with an increasing pH value of the environment. The highest binding capacity of the tested lactic acid bacteria was found for L. buchneri DSM 20057 with a maximum of 46.17 μg Cu bound per mg cell in deionize…
Study of the Interaction Mechanism in the Biosorption of Copper(II) Ions onto Posidonia oceanica and Peat
2012
A systematic approach was used to characterize the biosorption of copper(II) onto two biosorbents, Posidonia oceanica and peat, focusing on the interaction mechanisms, the copper(II) sorption–desorption process and the thermal behavior of the biosorbents. Sorption isotherms at pH 4–6 were obtained and the experimental data were fitted to the Langmuir model with a maximum uptake ( q max ) at pH 6 of 85.78 and 49.69mgg -1 , for P. oceanica and peat, respectively. A sequential desorption (SD) with water, Ca(NO 3 ) 2 , and EDTA was applied to copper-saturated biosorbents. Around 65–70% copper(II) were desorbed with EDTA, indicating that this heavy metal was strongly bound. The reversibility of …
Assessment of the influence of counter ions on biosorption of copper cations in brewer's spent grain - Waste product generated during beer brewing pr…
2019
Abstract The influence that conditioning leached ground barley grain (known as “brewer's spent grain” (BSG)) has on the effectiveness of copper cation sorption was analysed. Saturation with counter ions of functional groups present on the grain surface was carried out in hydrochloric acid, sodium hydroxide, sodium and calcium chloride solutions. For comparison, BSG was also conditioned in demineralised water. Spent barley grain is a by-product of the brewing industry which can be used as a biosorbent in the removal of heavy metals from waste water. Emphasis is placed on the effect of competitive sorption of copper and hydrogen cations and the negative influence of a solution alkalinisation …
Heavy metal sorption in biosorbents – Using spent grain from the brewing industry
2019
The sorption properties of brewer's spent grain (BSG) were assessed in terms of its usefulness in removing heavy metals from solutions. The specific objectives of the investigation involved studying sorption equilibrium and kinetics, assessing the influence of other cations on sorption efficiency, and examining the possibility of bed regeneration. The studies were carried out in a static system, with a constant ratio of solution volume to biosorbent mass, and using a flow through system. The affinity of metal cations to BSG functional groups was established and increased in the series: Mn2þzZn2þ < Ni2þ < Cd2þ < Cu2þ < Pb2þ. The BSG's sorption capacities (mmol g�1), determined using the Lang…
Biosorption of green and black tea polyphenols into Saccharomyces cerevisiae improves their bioaccessibility
2015
Infusions of green tea (GT) and black tea (BT) and the use of Saccharomyces cerevisiae as a natural matrix were employed to check the impact of biosorption on the possible fate of tea polyphenols in the gastrointestinal tract in terms of bioaccessibility and total antioxidant capacity (TEAC and ORAC assays). The maximum biosorption yields obtained were 47.61 ± 11.57 and 99.68 ± 5.25 mg/g from GT and BT infusions, respectively. A significant increase (p < 0.05) in the recovery of phenolic compounds was shown after in vitro digestion. The bioaccessible fractions generally exhibited higher antioxidant capacities in both tea infusions and suspensions of S. cerevisiae versus non-digested samples…
Leaf Biosorbents for the Removal of Heavy Metals
2018
The presence of heavy metals in waters is a global concern. Among various remediation technologies, biosorption is an attractive and promising process since in many cases, it is fast, selective, and highly efficient. Other advantages, such as applicability for various types of pollutants, simplicity, low cost, ease of operation, and the potential reusability of the adsorbents, make it beneficial. Nowadays, more and more green materials, raw or modified, are inclined to be explored instead of conventional adsorbents, within concept of Green Chemistry. This review focuses on the use of leaves-based biosorbents in raw or modified forms to sequestrate heavy metals from waters and wastewaters.