Person: Castro Ruiz, Laura
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First Name
Laura
Last Name
Castro Ruiz
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Ingeniería Química y de Materiales
Area
Identifiers
6 results
Search Results
Now showing 1 - 6 of 6
Item Batch and Continuous Chromate and Zinc Sorption from Electroplating Effluents Using Biogenic Iron Precipitates(Minerals, 2021) Rocha, Fabiana; Muñoz Sánchez, Jesús Ángel; González González, Felisa; Blázquez Izquierdo, María Luisa; Castro Ruiz, LauraNanoparticles of iron precipitates produced by a microbial consortium are a suitable adsorbent for metal removal from electroplating industry wastewaters. Biogenic iron precipitates were utilized as adsorbents for chromate and zinc in batch conditions. Furthermore, the iron precipitates were embedded in alginate beads for metal removal in fixed-bed columns, and their performance was evaluated in a continuous system by varying different operational parameters such as flow rate, bed height, and feeding system (down- and up-flows). The influence of different adsorption variables in the saturation time, the amount of adsorbed potentially toxic metals, and the column performance was investigated, and the shape of the breakthrough curves was analyzed. The optimal column performance was achieved by increasing bed height and by decreasing feed flow rate and inlet metal concentration. The up-flow system significantly improved the metal uptake, avoiding the preferential flow channels.Item Extracellular biosynthesis of gold nanoparticles using sugar beet pulp(Chemical Engineering Journal, 2010) Castro Ruiz, Laura; Blázquez Izquierdo, María Luisa; González González, Felisa; Muñoz Sánchez, Jesús Ángel; Ballester Pérez, AntonioSugar beet pulp was used as redactor agent for the synthesis of gold nanoparticles. The method developed is environmentally friendly and allows control of nanoparticles shapes by changing the initial pH value of aqueous HAuCl4 solutions. At low initial pH values, polygonal nanoparticles were obtained, mainly triangular and hexagonal shapes. Increasing the pH value, nanorods together with polygonal nanoparticles were produced. At higher initial pH, gold nanowires were formed. Gold biosorption took place at long reaction time, especially at low pH. This procedure could be useful to remove or recover metals from aqueous wastes. The synthesis of other metallic nanostructures such as silver and platinum could be achieved following a similar procedure.Item Biohydrometallurgy for Rare Earth Elements Recovery from Industrial Wastes(Molecules, 2021) Blázquez Izquierdo, María Luisa; González González, Felisa; Muñoz Sánchez, Jesús Ángel; Castro Ruiz, LauraBiohydrometallurgy recovers metals through microbially mediated processes and has been traditionally applied for the extraction of base metals from low-grade sulfidic ores. New investigations explore its potential for other types of critical resources, such as rare earth elements. In recent times, the interest in rare earth elements (REEs) is growing due to of their applications in novel technologies and green economy. The use of biohydrometallurgy for extracting resources from waste streams is also gaining attention to support innovative mining and promote a circular economy. The increase in wastes containing REEs turns them into a valuable alternative source. Most REE ores and industrial residues do not contain sulfides, and bioleaching processes use autotrophic or heterotrophic microorganisms to generate acids that dissolve the metals. This review gathers information towards the recycling of REE-bearing wastes (fluorescent lamp powder, spent cracking catalysts, e-wastes, etc.) using a more sustainable and environmentally friendly technology that reduces the impact on the environment.Item Continuous metal biosorption applied to industrial effluents: a comparative study using an agricultural by-product and a marine alga(Environmental Earth Sciences, 2017) Castro Ruiz, Laura; Bonilla, Luis; González González, Felisa; Ballester Pérez, Antonio; Blázquez Izquierdo, María Luisa; Muñoz Sánchez, Jesús ÁngelFixed-bed column experiments have been conducted to evaluate the removal of metals from real industrial wastewaters. The effluents tested were provided by two different metallurgical companies: Industrial Goñabe, a galvanizing plant, and Sao Domingos mine, an abandoned sulfide mine. Sugar-beet pulp, a by-product of the sugar industry, and brown alga Fucus vesiculosus were used as biosorbents. The influence of pH on the sorption process was insignificant for the tests using Industrial Goñabe wastewater. On the contrary, an increase of pH improved metal sorption uptake and yield and saturation rate in the case of the Sao Domingos wastewater. A lower metal concentration in Sao Domingos wastewater resulted in a higher availability of metal-binding sites on the biomass. Better sorption parameters for both real wastewaters were obtained using brown alga Fucus vesiculosus. At pH 5, Zn sorption in continuous mode increased from 36 to 48% for Industrial Goñabe wastewater and from 34 to 37% for Sao Domingos wastewater. In the latter case, copper sorption increased from 73 to 88%. Breakthrough points that determine the service time of columns were reached later using alga as biosorbent. For Zn, column adsorption performance improved substantially with alga and its service time by 5 times. In the case of Cu, the breakthrough point of the second column was not reached during 1750 min of experimentation. The results obtained reaffirm the industrial applicability of these techniques.Item Effectiveness of anaerobic iron bio-reduction of jarosite and the influence of humic substances(Hydrometallurgy, 2013) Castro Ruiz, Laura; García Balboa, María Del Camino; González González, Felisa; Ballester Pérez, Antonio; Blázquez Izquierdo, María Luisa; Muñoz Sánchez, Jesús ÁngelNowadays there is a growing interest in developing clean mining processes free of toxic chemicals. Biotechnology could be a cost-effective and environmentally friendly alternative to traditional leaching methods. Jarosite is an important sulfate mineral that occurs naturally and also can be produced as a waste in industrial processes. In this work, bioreduction of jarosite using Shewanella putrefaciens and a natural consortium under anaerobic conditions is presented as an acceptable bioleaching method. Moreover, the influence of humic substances that appear in natural environments acting as electron shuttles between microorganisms and insoluble oxides has been investigated. One key factor for the industrial implementation of anaerobic bioleaching is the metal recovery from minerals. The precipitates formed as products of dissimilatory iron reduction, the bacterial ability to obtain ferrous ions in solution and the stimulation of insoluble Fe(III) ores reduction by electron shuttles have been examined in this research.Item Biosynthesis of gold nanowires using sugar beet pulp(Process Biochemistry, 2011) Castro Ruiz, Laura; Blázquez Izquierdo, María Luisa; Muñoz Sánchez, Jesús Ángel; González González, Felisa; García Balboa, María Del Camino; Ballester Pérez, AntonioSugar beet pulp was used as reductor and capping agent for the synthesis of gold nanowires. Reduction of tetrachloroaurate with sugar beet pulp is a simple, room temperature and environmentally friendly method. Polysaccharides and proteins are involved in the bioreduction and synthesis of nanoparticles. Different pH and molar concentration ratios of HAuCl4 were studied for the synthesis of gold nanowires. The formation of nanowires was induced by both basic mediums, due to the competence between biomolecules and hydroxide ions, and high concentrations of gold ions, because of the lack of capping agent to stabilize the preliminary nanoparticles formed that stick together producing wire-like nanostructures instead of nanospheres. This method allowed the synthesis of crystalline gold nanowires in the absence of a surfactant or polymer to direct nanoparticle growth, and without externally added seed crystallites. The synthesis of other metallic nanostructures such as silver and platinum could be achieved following a similar procedure.