J. Jaime Sadhwani Alonso

A novel catalyst, composed of silver phosphate (Ag₃PO₄) deposited on a magnetic material containing titanium dioxide (TiO₂) and ferromagnetite (Fe₃O₄), was synthesized and tested with wastewater from the maintenance system of a swimming pool and from the secondary effluent of a wastewater treatment plant (WWTP). The magnetic material Ag₃PO₄@1-TiO₂-Fe₃O₄ presented a slightly lower photoactivity than bare Ag₃PO₄ but was able to remove over 64% COD from the secondary effluent of a WWTP and over 75% organic UV filters from a swimming pool wastewater. The material was easily recovered from the treated water with a magnet and could be reused at least four times. The efficiency loss after five reuses was 15%. The dissolution of silver after the photocatalytic reaction was over 80 mg·L⁻¹ for bare Ag₃PO₄ and less than 500 μg·L⁻¹ for the magnetic composites. The magnetic support prevents the dissolution of silver. The materials that contained Ag₃PO₄ showed antibacterial properties under dark conditions. The photocatalytic efficiency of Ag₃PO₄ and commercial TiO₂ was similar under sunlight, both for the removal of UV filters at µg·L⁻¹ concentrations from swimming pool wastewater, and for the removal of mild COD loads from a WWTP effluent (initial COD: 110 mg·L⁻¹).

La terminología que envuelve al desarrollo sostenible provoca ambigüedades y posturas enfrentadas en su interpretación que dispersa los objetivos y debilita una acción conjunta. Pese a todo, la necesidad de abordar el desarrollo sostenible en la Educación Ambiental es cada vez mayor y, por tanto, se debe tener presente todos los aspectos (económicos, sociales, ecológicos…) que comprenden la propia razón de ser de la sostenibilidad.Las universidades no son ajenas al nuevo desafío de la Educación Ambiental en el desarrollo sostenible, ya que sus compromisos, valores y estudios rebasan la misma institución por el papel tan predominante que posee en la sociedad. Las propuestas de la sostenibilidad en el ámbito universitario son múltiples: sistemas de energía renovables, disminución del consumo, gestión de los residuos, fomentación de la ética ambiental o incremento de las investigaciones para favorecer un desarrollo sostenible real. A través de todas estas medidas, se estaría marcando una conducta y sirviendo de ejemplo al conjunto de la sociedad. En definitiva, la presente investigación es una exploración sobre la inevitable unión entre el desarrollo sostenible y la Educación Ambiental, pero centrándose en el ámbito universitario y aportando algunas propuestas de sostenibilidad.

Water has a huge economic, social and environmental importance, so the search of the precious liquid has become an intensive process in water policies of different countries. Therefore, the provision of water suitable for human consumption has now become a problem of vital importance for the population. The water desalination has led to a new strategy for water supply, especially in areas with high water stress and with opportunities of abundant new alternative sources of supply (seawater and brackish). Desalination technologies allow greater savings and efficiency in water use, exploitation of resources that were unusable previously like the peculiar case of sea water, as well as a greater guarantee of supply in terms of availability and quality, particularly in areas with poor water resources. In these areas often merge several factors that greatly favor the use of desalination. The Canary Islands are a clear example of this, as it has a large population, a great tourist industry, a shortage of the liquid element and a high demand for agricultural irrigation that conditions the availability and the need of new sources of high quality water. Water desalination, in the water policy of the Canary Islands, has been deeply rooted in the last forty years, allowing to solve and overcome the shortage and to ensure a quality suitable for human consumption. This article discusses the importance and significance that has had water desalination in the Canary Islands, made with a historical development of the evidence and key outcomes.