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In the last quarter of 2021, there was a very significant eruption of the Cumbre Vieja volcano on the island of La Palma, belonging to the Canary Islands, Spain. It generated a large amount of pyroclastic volcanic materials, which must be studied for their possible applicability. This work studies the properties and applicability of the lava and volcanic ash generated in this process. The need for reconstruction of the areas of the island that suffered from this environmental catastrophe is considered in this study from the point of view of the valuation of the waste generated. For this purpose, the possibility of using the fine fraction of ashes and lava as a supplementary cement material (SCM) in the manufacture of cement is investigated. The volcanic material showed a chemical composition and atomic structure suitable for replacing clinker in the manufacture of Portland cement. In this study, the cementing and pozzolanic reaction characteristics of unprocessed volcanic materials and those processed by crushing procedures are analysed. To evaluate the cementitious potential by analysing the mechanical behaviour, a comparison with other types of mineral additions (fly ash, silica fume, and limestone filler) commonly used in cement manufacture or previously studied was carried out. The results of this study show that volcanic materials are feasible to be used in the manufacture of cement, with up to a 22% increase in pozzolanicity from 28 to 90 days, showing the high potential as a long-term supplementary cementitious material in cement manufacturing, though it is necessary to carry out crushing processes that improve their pozzolanic behaviour. [ABSTRACT FROM AUTHOR]

In the eruptive event of Tajogaite (2021) in La Palma, Canary Islands, large quantities of volcanic ash were accumulated, affecting the local environment and urban areas. In this study, volcanic ash sampled from urban areas (catalogued as municipal waste (20 03 03) by the European Wastes Catalogue) were converted into zeolites by hydrothermal synthesis at 100 °C with previous alkaline fusion at 550 °C with distilled water. During this process, new phases of zeolite principally type X and sodalite have been identified by XRD at 2 h of incubation. These zeolites, with the course of incubation time, present competitive processes where the transformation into sodalite develops after 24 h as the predominant phase. The synthesized zeolitic material presents a high concentration as impurities in Fe 2 O 3 (13.70 wt%), Na 2 O (12.70 wt%), CaO (11.65 wt%), and TiO 2 (3.89 wt%) coming from the volcanic ash and NaOH introduced in the synthesis methodology. These impurities impart different physicochemical capabilities to the zeolitic material. The application of zeolites obtained in a preliminary fluoride adsorption experiment with volcanic leachate water rich in fluoride has been tested in a novel way. Removal efficiencies of 41.4% at acidic pH (5.77) have been obtained with 2 g L -1 adsorbent zeolitic material doses. A value-added material is obtained and applied in a preliminary way to solve a problem generated by the volcanic ash itself, allowing the End of Waste status and meeting different objectives of the sustainable development goals of the UN Agenda 2030., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

• Volcanic ash (VA) from the Cumbre Vieja volcano (La Palma, Spain) was characterized. • VA was activated with NaOH/waterglass activator (1.46 SiO 2 /Na 2 O modulus) • Compressive strength of 80 MPa was reached for mortars cured at 65 °C for 7 days. • The feasibility of using recently erupted volcanic material was demonstrated. • This is a fascinating solution for the VA valorization in the reconstruction tasks. One of the most critical issues after a volcanic eruption is managing damaged infrastructure and human health. This study aims to promote the valorization of non-weathered volcanic ash (VA) from the Cumbre Vieja volcano (La Palma Island – Spain) in the production of alternative cements. A detailed study related to the characterization of VA was performed, and its use in the production of alkali-activated cements is proposed. Promising results, achieving about 80 MPa in compression, indicated that using a cementing material based on VA could be a fascinating solution for the VA valorization and the reconstruction of the affected infrastructure of La Palma Island, especially in producing prefabricated elements. [ABSTRACT FROM AUTHOR]

The recent volcanic eruption on the island of La Palma has aroused the concern of banana producers and consumers, given that in its area of influence there are thousands of hectares of banana plantations with an annual production of about 100 million kilos for export. Since volcanoes are one of the main natural sources of heavy metal contamination, we sampled bananas from the affected area and determined the concentrations of 50 elements (Ag, Al, As, Au, Ba, Be, Bi, Cd, Ce, Co, Cr, Cu, Cu, Dy, Er, Eu, Fe, Ga, Gd, Hg, Ho, In, La, Lu, Mn, Mo, Nb, Nd, Ni, Os, Pb, Pd, Pm, Pr, Pt, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Th, Ti, Tl, Tm, U, Y, Yb and Zn). The levels of 36 elements were elevated but the washing implemented after the eruption can remove a good part. After the washout, bananas have elevated levels of Fe, Al, Ti, V, Ba, Pb, most of the rare earth elements, Mo, and Co. In all cases, except Mo, the elevation is much higher in the peel than in the flesh. In the case of Mo, the elevation in banana flesh would translate into a higher nutritional intake of this trace element, which could represent up to 35% of the daily nutritional requirements. Exposure to toxic or potentially toxic elements, does not represent a health risk, since would not exceed 5% of the tolerable daily intake, even in the worst-case scenario., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The article focuses on the volcanic island of Lanzarote, Canary Islands, Spain. It is one of the most arid parts of the European Union. During the volcanic eruptions in 1730--36, a third of the island was covered with lava and pyroclastic material. In areas under basaltic tephra, an agrosystem has been created that allows a kind of dry farming that has become an important component of the local economy. The layer of natural tephra mulch is effective in conserving soil and water.