Water pollution represents a significant challenge for the scientific community, especially in the case of heavy metals, aromatic molecules and dyes contamination. [1] Focusing on the first class of pollutants, i.e. heavy metals, this sort of contamination is typical of industrial wastewaters [2] and adsorption is nowadays the most common approach researchers are opting for to remove these pollutants from industrial effluents before their discharge in groundwaters; among all the alternatives, natural polymers are undoubtedly the most interesting materials for this application, ranging from polysaccharides to chitosan, zeolites, cellulose or lignin-based materials. [1-3] The reasons behind such a widespread diffusion of natural polymers for heavy metal sorption can be rapidly listed: (i) natural polymers are generally cheap and ensure higher biocompatibility and biodegradability than synthetic compounds, [4] (ii) several plant or animal-derived monomers show intrinsic binding affinity towards metal ions [1,3] and, last but not least, (iii) multicomponent biomaterials’ properties can be appropriately tuned by changing the type and ratios of starting materials. [5] On the other side, all that glitters in not gold and it must be underlined that films made of natural polymers suffer from poor chemical and mechanical properties and high solubility, thus strongly limiting their actual applicability in real cases. [5] In this scenario, we put in place our knowledges on chemometric tools for multivariate optimization aiming at tuning the properties of starch/glycerol/CMC films, obtained by casting deposition, to improve their chemical and mechanical properties and to achieve the goal requirements for their actual applicability. We identified the suitable range of starch, glycerol and CMC percentages, as shown in Figure 1a, in which films enough resistant to be handled and tested but exhibiting much different properties were always achieved. [5] Then, according to Mixture Design methodology, [6] the relevant compositions to be synthesized to model films’ features were identified, highlighted as circles in Figure 1a, synthesized according to the optimized procedure [5] and characterized. [7,8] Characterization measurements allowed to determine several features of the samples, mainly mechanical properties, swelling, water vapour absorption and solubility, together with thermal behaviour. [5,7,8] Each feature was then separately modelled according to Mixture Design methodology to describe and predict the trend of the property of interest in the range of main components previously defined. An example is reported in Figure 1b in the case of swelling. Finally, correlations between the modelled features were identified by means of Principal Component Analysis [9] to identify the ideal composition for heavy metal sorption in real samples.
Multivariate optimization of starch/glycerol/CMC films by casting deposition: towards cheap and tuneable biomaterials for metal ions sorption
Denise BELLOTTI;Maurizio REMELLI;
2024
Abstract
Water pollution represents a significant challenge for the scientific community, especially in the case of heavy metals, aromatic molecules and dyes contamination. [1] Focusing on the first class of pollutants, i.e. heavy metals, this sort of contamination is typical of industrial wastewaters [2] and adsorption is nowadays the most common approach researchers are opting for to remove these pollutants from industrial effluents before their discharge in groundwaters; among all the alternatives, natural polymers are undoubtedly the most interesting materials for this application, ranging from polysaccharides to chitosan, zeolites, cellulose or lignin-based materials. [1-3] The reasons behind such a widespread diffusion of natural polymers for heavy metal sorption can be rapidly listed: (i) natural polymers are generally cheap and ensure higher biocompatibility and biodegradability than synthetic compounds, [4] (ii) several plant or animal-derived monomers show intrinsic binding affinity towards metal ions [1,3] and, last but not least, (iii) multicomponent biomaterials’ properties can be appropriately tuned by changing the type and ratios of starting materials. [5] On the other side, all that glitters in not gold and it must be underlined that films made of natural polymers suffer from poor chemical and mechanical properties and high solubility, thus strongly limiting their actual applicability in real cases. [5] In this scenario, we put in place our knowledges on chemometric tools for multivariate optimization aiming at tuning the properties of starch/glycerol/CMC films, obtained by casting deposition, to improve their chemical and mechanical properties and to achieve the goal requirements for their actual applicability. We identified the suitable range of starch, glycerol and CMC percentages, as shown in Figure 1a, in which films enough resistant to be handled and tested but exhibiting much different properties were always achieved. [5] Then, according to Mixture Design methodology, [6] the relevant compositions to be synthesized to model films’ features were identified, highlighted as circles in Figure 1a, synthesized according to the optimized procedure [5] and characterized. [7,8] Characterization measurements allowed to determine several features of the samples, mainly mechanical properties, swelling, water vapour absorption and solubility, together with thermal behaviour. [5,7,8] Each feature was then separately modelled according to Mixture Design methodology to describe and predict the trend of the property of interest in the range of main components previously defined. An example is reported in Figure 1b in the case of swelling. Finally, correlations between the modelled features were identified by means of Principal Component Analysis [9] to identify the ideal composition for heavy metal sorption in real samples.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
