Evaluation of the biocidal efficacy of titanium dioxide coatings for water purification

世界卫生组织估计，世界上一半以上的人口供水受到微生物的污染，其中许多往往是致病的，这突显出需要采取具有成本效益和无毒的战略来处理大量水。一种突破性的水处理策略得到了广泛的接受，那就是将分散剂引入水供应中的纳米光催化剂。当光催化剂暴露在紫外光或可见光范围的光子下时，会产生高度活性的氧自由基，分解和分解有机分子和微生物，将它们转化为水和二氧化碳。二氧化钛(TiO2光催化剂)是一种很有前途和广泛应用的光催化剂，它无毒，不溶于水，耐大多数化学物质，如酸、碱或溶剂，并且相对便宜。 不幸的是，这些纳米颗粒不能轻易地从处理后的水中去除。摄取纳米颗粒对人类健康的潜在长期后果是一个主要的担忧，因为已经在细胞系和测试生物体中注意到了多种不良影响。Simulant Inc.提出的一种新策略是将二氧化钛晶体固定在胶粘剂表面，作为一种更可行、更安全的替代方案，以实现经济有效的水处理。一种改进的热喷涂工艺正在进行设计，以实现高浓度的锐钛矿型生物杀菌二氧化钛。这项拨款提案旨在评估使用革兰氏阴性、革兰氏阳性和芽胞形成细菌的工程二氧化钛涂层的生物杀灭活性。所产生的数据将在使用固定化技术的水处理厂的工程中发挥关键作用 TiO2光催化电池。

The World Heath Organization estimates that over half the world's population water supplies are contaminated with microorganisms, many of which are often pathogenic- underscoring the need for cost effective and non-toxic strategies for the treatment of large volumes of water. A breakthrough water treatment strategy that has gained widespread acceptance is the dispersant into water supplies of a nano-photocatalysts. When photocatalysts are exposed to photons in the UV or visible light range, highly reactive oxygen radicals are generated that decompose and disintegrate organic molecules and microbes, transforming them into water and CO2. A promising and widely used photocatalyst is titanium dioxide (TiO2), which is non-toxic, insoluble in water and resistant to most chemicals, such as acids, bases or solvents and relatively inexpensive. Unfortunately, the nanoparticles cannot be easily removed from the treated water. The potential long-term consequences to human health of ingesting the nanoparticles are a major concern since multiple adverse effects have been noted with cell lines and test organisms. A novel strategy proposed by Simulant Inc. is to immobilize Ti02 crystals on adhesive surfaces as a more viable and safe alternative to achieve economical and effective treatment of water. A modified Thermal Spray process is being engineering to achieve high concentrations of the biocidal, anatase form of TiO2. The grant proposal aims to evaluate the biocidal activities of the engineered TiO2 coating using gram-negative, gram-positive and spore forming bacteria. The data generated will play a critical role in the engineering of water treatment plants employing immobilized TiO2 photocatalytic cells.