Multifunctional thin film nanocomposite membranes for water treatment

根据世界经济论坛2015年发布的《全球风险报告》，供水危机是未来十年社会发展面临的最大全球风险。今天，全世界有超过10亿人无法获得清洁、安全的饮用水。到2030年，全球水需求预计将超过可持续供水的40%。水危机的主要表现是农业、工业和家庭部门过度使用和污染水资源。由于可利用的淡水资源有限（占地球水资源的0.007%），可持续经济增长的唯一可行选择是废水处理。事实上，消除遗留尾矿废物是全球的首要任务，因为水正在迅速成为许多应用中的关键商品。** 加拿大的油砂工业是水资源管理效率低下的一个例子，因为在露天开采作业中，开采一桶石油需要2-4桶水。这种大量的淡水消耗威胁着加拿大的水安全，加拿大拥有世界淡水的约20%。因此，加拿大水资源的可持续性在很大程度上取决于对受工艺影响的水的处理。膜分离工艺通过提供更高的分离效率和更小的占地面积，为当前的能源和材料密集型工艺（例如蒸馏、离子交换和石灰软化剂）提供了有前途的替代方案。然而，膜对污染的高度敏感性及其对环境触发器的不可切换的物理化学性质带来了挑战，这是本研究计划的重点。** 拟议研究的目标是开发新型刺激响应薄膜纳米复合膜，其基于外部刺激改变其渗透特性和污染特性，例如pH值，温度，离子强度和电场的脉冲变化。这将首先通过将功能性纳米材料嵌入聚合物基质中来实现，然后通过将功能性聚合物结合到表面来诱导响应性。一般的想法是将纳米颗粒和响应性聚合物的电、表面电荷、亲水性和分子筛性质诱导到基膜。合成的膜，除了充当分离屏障之外，（i）选择性地氧化进料中的有害有机物质，（ii）显示出可针对不同类型的进料进行调节的抗氧化性能，以及（iii）具有可调节的分离特性。与这些新的膜相结合的膜过程可以通过新的分离技术为加拿大的水管理举措做出贡献。

According to the Global Risks Report issued by the World Economic Forum in 2015, a crisis in water supply is the foremost global risk to the development of societies over the next decade. Today, more than 1 billion people around the world don't have access to clean, safe drinking water. Global water requirements are projected to be pushed beyond sustainable water supplies by 40% by 2030. The principle manifestation of the water crisis is overuse and pollution of water resources in agriculture, industry, and domestic sectors. With finite accessible freshwater resources (0.007% of the planet's water), the only viable option to sustainable economic growth is the treatment of wastewater. Indeed, eliminating legacy tailing waste is a top global priority, as water is rapidly becoming the crucial commodity in many applications. ******Canada's oil sands industry is an example of an inefficient water management as it uses 2-4 barrels of water for extraction of one barrel of oil in open-pit mining operation. This heavy fresh water consumer threatens the water security of Canada, a country that holds approximately 20% of the world freshwater. Hence, the sustainability of Canada's water resources greatly depends on the treatment of process-affected water. Membrane separation processes offer a promising alternative to current energy- and material-intensive processes such as distillation, ion exchange, and lime softener by providing higher separation efficiency and a smaller footprint. However, high susceptibility of membranes to fouling and their non-switchable physicochemical properties to environmental triggers creates challenges which are the focus of this research program. ******The goal of the proposed research is to develop novel stimuli-responsive thin film nanocomposite membranes, which alter their permeation characteristics and fouling properties based on external stimuli, such as impulsive change in pH, temperature, ionic strength and electric field. This will be accomplished first by embedding functional nanomaterials within the polymer matrix, then inducing responsiveness via incorporating functional polymers to the surface. The general idea is to induce electrical, surface charge, hydrophilic and molecular sieve properties of both nanoparticles and responsive polymers to the base membrane. The synthesized membranes, in addition to acting as a separation barrier, (i) selectively oxidize harmful organic matter in the feed, (ii) display antifouling properties that can be tuned for different types of feed, and (iii) possess tunable separation characteristics. The membrane processes coupled with these novel membranes can contribute to Canada's water management initiatives via novel separation technologies.