Responsive cellulose fibre and polymer-based adsorbents for contaminant removal

工业废水中的污染物源源不断地排放到环境中，造成严重的土壤和水体污染。在解决环境问题的各种方法中，吸附技术因其高效和经济可行而被认为是最具竞争力的污染物去除方法之一。尽管已报道了各种吸附剂，但与智能性能和回收难度相关的关键问题仍然存在。*拟议的研究目标是开发具有内在能力的绿色、刺激响应型纤维素纤维和聚合物基吸附剂，这些吸附剂具有在外部触发因素(如pH、温度或氧化还原反应)引起的可逆改变其构型或缔合的能力，从而促进吸附剂的吸附和回收。这项研究的长期愿景是使用智能和环境友好的吸附剂来解决环境问题，这种吸附剂可以调节吸附和解吸。具体目标是：*(I)通过各种方法开发一系列具有响应行为(即热、pH或氧化还原响应特性)的基于纤维素纤维的智能绿色吸附剂；和*(Ii)以纳米CaCO3为可萃取性填料，通过新型多孔碳酸钙-模板自由基共聚和反应挤出合成响应性聚合物吸附剂。*为实现上述目标，提出了两个子项目：*1.响应性纤维素纤维基生物吸附剂，主要通过各种单体的表面诱导活性自由基聚合、半互穿聚合物网络和预制的响应性聚合物在纤维表面接枝而制备。*2.以CaCO3为模板或可萃取性填料制备的聚合物吸附剂与两种制备聚合物吸附剂的创新工艺相结合，即多孔CaCO3-模板化聚合和反应挤出。*所得到的智能吸附剂及其吸附和解吸行为将使用各种最先进的技术进行全面表征。*建议的研究结果将从根本上指导未来新型和智能生物吸附剂的分子和结构设计，并促进吸附剂的回收。最终，将为加拿大林业和纸浆造纸行业创造一系列增值纤维素纤维产品，这是加拿大一个重要的工业部门，2015年对名义GDP的总贡献超过210亿美元(NRC加拿大)。与智能聚合物吸附剂以及在生物材料和制药方面的可扩展应用相结合，其好处将进一步放大。拟议的研究还对HQP培训产生了很大影响，从而确保了加拿大环境部门和纸浆造纸行业HQP的稳定供应。

The contaminants from industrial effluents have been persistently released into the environment and caused serious soil and water pollution. Among various approaches for tackling the environmental concerns, the adsorption technique is regarded as one of the most competitive methods for contaminant removal due to its high efficiency and economic feasibility. Despite of various adsorbents reported, the key issues related to smart performance and recovering difficulty still remain.****The proposed research targets the exploitation of green-based, stimulus-responsive cellulose fibre and polymer-based adsorbents with the intrinsic capability to reversibly change their configuration or association caused by an external trigger such as pH, temperature or redox reaction, thus facilitating the adsorption and recovery of adsorbents. The long-term vision of the research is to address the environmental concerns using smart and environmental-friendly adsorbents which can modulate the adsorption and desorption. The specific goals are:****(i) to develop a range of smart cellulose fibre-based green adsorbents incorporated with responsive behaviors (i.e., thermal, pH or redox responsive properties) via various approaches; and****(ii) to synthesize responsive polymeric absorbents via novel porous calcium carbonate-templated free-radical copolymerization and reactive extrusion with nano-CaCO3 as extractable fillers.****To achieve the objectives above, two subprojects are proposed:****1. Responsive cellulose-fibre based bioadsorbents mainly prepared by surface-induced living free-radical polymerization of various monomers, semi-interpenetrating polymer network and grafting of pre-prepared responsive polymers on fibre surfaces.****2. Polymeric adsorbents prepared using CaCO3 as template or extractable filler which are associated with two innovative processes for fabricating polymer adsorbents, i.e., porous CaCO3-templated polymerization and reactive extrusion.****The resulting smart adsorbents and the sorption and desorption behavior will be comprehensively characterized using various state-of-art techniques.****The findings of the proposed research will fundamentally guide future molecular and structural designs for novel and smart bioadsorbents, and facilitate the recovery of adsorbents. Ultimately, a range of value-added cellulose fibre products will be created for the Canadian forestry and pulp and paper industries, which represent an important Canadian industrial sector that made a total contribution of more than $21 billion to nominal GDP in 2015 (NRC Canada). In conjunction with smart polymer adsorbents and extendable applications in biomaterials and pharmaceuticals, the benefits will be further magnified. The proposed research also has strong impact on HQP training, thus ensuring a steady supply of HQP for the Canadian environmental sector and pulp & paper industry.***