6 research outputs found

    INDICATORS FOR SUSTAINABILITY IN INDUSTRIAL SYSTEMS CASE STUDY: PAPER MANUFACTURING

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    The paper describes a framework for promoting sustainability by using indicators for sustainable production. The concept of sustainable production is described as it is viewed by various organisms actions involved in the analysis of the sustainable industrial systems.The measure of sustainability is approached considering indicators of sustainable production, addressing both their dimensions and qualitative and quantitative features.The proposed framework refines the sustainability dimension for a case study which envisages sustainability in paper manufacturing. The analysis takes into account the life cycle analysis for the considered process since the environmental impact is seen as an essential sustainability indicator. Paper recycling and reuse is associated environmental and social costs, as a preferred alternative in waste minimization hierarchy in the manufacturing of non-trees eco-friendly paper.Proactive initiatives to improve the environmental performances of production process are considered as powerful tools for improving the paper manufacturing environmental footprint

    Calcium carbonate-carboxymethyl chitosan hybrid materials

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    In the present work, precipitated calcium carbonate (PCC) and carboxymethyl chitosan (CMC) were prepared to obtain new hybrid materials used in papermaking. In the first step, oc‐ curred the precipitation of CaCO3 in solution containing CMC at different levels (0.5%, 1%, and 1.5%). In the second step, PCC–CMC hybrid material (25%) was added to pulp suspension, and the sheets were made. The effect of PCC–CMC on paper properties (mechanical and optical) was sys‐ tematically investigated. Breaking length, the brightness and opacity of the sheets obtained with the PCC–CMC material were better than the sheets fabricated with the unmodified PCC at similar levels of content

    POTENTIAL VALORISATION OF PROTOBIND 1000 AS ADSORBENT FOR Pb 2+ AND Zn 2+

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    The adsorption of metal ions from increasing concentrations in aqueous solutions by modified straw lignin Protobind 1000 was studied. The effect of metallic ion concentrations (from 20.72 to 207.2 mg·L-1 for Pb2+ and from 6.538 to 65.38 mg·L-1 for Zn2+) and contact time (30, 60 and 90 minutes) were studied at pH = 6 and 200C. Langmuir and Freundlich isotherm equations were applied to assess equilibrium data and the kinetics of the adsorption processes were analysed using Lagergren pseudo first order and Ho&McKay pseudo second order models. The results show that the adsorption processes reached equilibrium after 90 minutes, but similar values were registered after 60 minutes. The Freundlich isotherm described the process better, denoting chemisorption with the formation of ion-lignin complex structures. The Ho&McKay model fit the adsorption data better with regression coefficients equal to 1 compared to the Lagergren model, where the regression factors varied between 0.72 and 0.95. For the maximum concentration of lead solution and the longest adsorption time of 90 minutes, the Ho&McKay model predicted an equilibrium capacity qe of 13.1406 mg·g-1 compared to the 13.1398 mg·g-1 obtained. For zinc adsorption, the same maximum concentration and time were considered, and the pseudo-second order model predicted a qe of 12.6743 mg·g-1 compared to the obtained value of 12.6714 mg·g-1. The uptake of lead was greater on 0.15 g of adsorbent (a maximum of 27.23 mg·g-1) than the zinc uptake (a maximum of 8.28 mg·g-1), for all analysed concentrations

    Potential valorisation of Protobind 1000 as adsorbent for Pb2+ AND Zn2+

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    The adsorption of metal ions from increasing concentrations in aqueous solutions by modified straw lignin Protobind 1000 was studied. The effect of metallic ion concentrations (from 20.72 to 207.2 mg·L-1 for Pb2+ and from 6.538 to 65.38 mg·L-1 for Zn2+) and contact time (30, 60 and 90 minutes) were studied at pH = 6 and 200C. Langmuir and Freundlich isotherm equations were applied to assess equilibrium data and the kinetics of the adsorption processes were analysed using Lagergren pseudo first order and Ho&McKay pseudo second order models. The results show that the adsorption processes reached equilibrium after 90 minutes, but similar values were registered after 60 minutes. The Freundlich isotherm described the process better, denoting chemisorption with the formation of ion-lignin complex structures. The Ho&McKay model fit the adsorption data better with regression coefficients equal to 1 compared to the Lagergren model, where the regression factors varied between 0.72 and 0.95. For the maximum concentration of lead solution and the longest adsorption time of 90 minutes, the Ho&McKay model predicted an equilibrium capacity qe of 13.1406 mg·g-1 compared to the 13.1398 mg·g-1 obtained. For zinc adsorption, the same maximum concentration and time were considered, and the pseudo-second order model predicted a qe of 12.6743 mg·g-1 compared to the obtained value of 12.6714 mg·g-1. The uptake of lead was greater on 0.15 g of adsorbent (a maximum of 27.23 mg·g-1) than the zinc uptake (a maximum of 8.28 mg·g-1), for all analysed concentrations

    Design of Functional Polymer Systems to Optimize the Filler Retention in Obtaining Cellulosic Substrates with Improved Properties

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    In the present work, the possibility of increasing the calcium carbonate (CaCO3) content in sheets of paper to optimize their properties was investigated. A new class of polymeric additives for papermaking is proposed as well as a method for their use in paper sheet containing the CaCO3 precipitated addition. Calcium carbonate precipitated (PCC) and fibers cellulose were adjusted with a cationic polyacrylamide flocculating agent (polydiallyldimethylammonium chloride (plyDADMAC) or cationic polyacrylamide (cPAM)). PCC was obtained in the laboratory by a double-exchange reaction between calcium chloride (CaCl2) and sodium carbonate (Na2CO3) suspension. After testing, the dosage of PCC was established at 35%. To improve the systems of additives studied, the materials obtained were characterized and their optical and mechanical properties were analysed. The PCC had a positive influence over all of the paper samples, but in the case of use of cPAM and polyDADMAC polymers the paper obtained had superior properties compared to the paper obtained without additives. Also, the samples obtained in the presence of cationic polyacrylamide exhibit superior properties to those obtained in the presence of polyDADMAC

    Elemental and macromolecular modifications in Triticum aestivum L. plantlets under different cultivation conditions.

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    Young wheat plantlets (wheatgrass), represent a significant source of minerals, enzymes, vitamins, while also rich in phenolics and chlorophylls, with considerable bioactivities. As the biosynthesis of such compounds may be influenced by growth conditions, the current research assesses wheatgrass composition in soil based and hydroponic systems, using water with different elemental composition. FTIR spectroscopy did not reveal significant variations between juice and extracts cultivated in different setups. Surface elemental composition indicated higher Na, P, Si concentrations in hydroponic plants, while AAS analyses showed increased Ca and Mn in soil presence. HPLC-MS of extracts showed that soil and spring water increased chlorophyll and hydroxychlorophyll a concentrations. Phenolic contents were higher in hydroponic plants, while maximum values were recorded for spring water. Radical scavenging activity was stimulated by the use of spring water. Results indicate that wheatgrass with improved mineral and macromolecular composition may be obtained using accessible cultivation setups
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