Photoactive Ion Exchange Resins, 1998 Environmental Conference Proceedings

Mohamed a. Ibrahim

Mark Nimlos

Jonathan Filley

National Renewable Energy Laboratory(NREL)

As the forest product industry move towards closed cycle pulping processes, the ability to remove non-process elements from water streams becomes more critical. Dissolved species such as calcium, magnesium and transition metals such as manganese, iron and anions such as oxalates can build up in process waters and lead to scale formation and catalytic decomposition of bleaching agents. Ion exchange and precipitation using sequestering agents are currently used as technologies to help with this problem. We are developing a new class of photoactive ion exchange resins that can be regenerated with less energy and solvents than conventional resins and will be effective for recycling, water reduction and pollution prevention. As a proof of concept, we have synthesized several photoactive dyes based on spiropyran and tested for its imetal binding ability. These dyes have also been anchored onto solid support and its metal and anion binding ability were studied. Initial results were encouraging and could lead to product development in future.