SBIR Phase I: A Transformational Method to Extract Polychlorinated Biphenyls (PCBs) from Building Masonry

这个小企业创新研究（SBIR）第一阶段项目的广泛影响是解决影响我们老化的学校和基础设施的遗留多氯联苯（pcb）问题。美国环境保护署（EPA）估计，在1979年禁止使用多氯联苯之前，多达5.5万所学校和80万幢政府和非政府建筑可能使用了含多氯联苯的油漆、填充物、塑料和粘合剂。简单地移除含多氯联苯的源头，希望它能消除危害，这已被证明是徒劳的，因为越来越多的数据显示，风化填缝中的多氯联苯可以渗入6英寸深的邻近多孔砌体（如混凝土、砖和砂浆）。目前，完全拆除和部分拆除（即部分拆除）是epa批准的唯一PCB拆除方案，这两种方案都迅速填满了少数愿意接受的垃圾填埋场。拟议中的技术创新将把一项从油漆中提取多氯联苯的休眠政府专利转化为一种非破坏性处理方法，该方法可以穿透并提取建筑砌体中吸收的多氯联苯。这种创新将对政府机构和学校改造委员会产生直接和有益的影响，他们无法承担拆除旧的重建新。SBIR第一期项目旨在证明两种专有溶剂-浆料配方在去除污染源（如填缝）后从不同砌体类型中提取多氯联苯的可行性。溶剂膏体直接涂抹在被污染的砌体表面，经过预先确定的处理时间刮掉。一旦使用，溶剂糊中的亲脂性醇就会渗透到砖石的开放孔空间中，并溶解沿途遇到的PCB分子。将多氯联苯从无机砌体颗粒中解吸到所应用的浆料中的过程是通过毛细管作用由亲脂醇将疏水多氯联苯吸引到浆料中来的。技术挑战包括在季节性凉爽（50°F）潮湿的天气中，解吸添加到油漆、填塞和粘合剂中的疏水性Aroclors（例如1248、1254、1260）的粘性谱。由于替代PCB处理技术的成功商业化需要根据PCB法规（40 CFR 761）获得EPA的批准，因此将根据法规严格的1ppm高占用率清洁标准评估两种溶剂糊的性能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact of this Small Business Innovation Research (SBIR) Phase 1 project is solving the legacy polychlorinated biphenyls (PCBs) problem impacting our aging schools and infrastructure. The U.S. Environmental Protection Agency (EPA) estimates as many as 55,000 schools and 800,000 government and non-government buildings may have been constructed with PCB-laden paints, caulks, mastics and adhesives before the 1979 PCBs ban. Simply removing the PCB-laden source in hopes it will eliminate the hazard has proven futile as a growing body of data is revealing PCBs from weathered caulk can leach as deep as 6-inches into adjacent porous masonry (e.g., concrete, brick, and mortar). Currently, total demolition and select removal (i.e., partial demolition) are the only EPA-approved PCB removal options and both are quickly filling up the handful of landfills willing to take it. The proposed technical innovation will transform a dormant government patent that extracts PCBs in paint, into a non-destructive treatment method that penetrates and extracts PCBs absorbed in building masonry. Such an innovation will have a direct and beneficial impact on the government agencies and school renovation commissions who cannot afford to demolish the old and rebuild new. This SBIR Phase 1 project proposes to demonstrate the feasibility of two proprietary solvent-paste formulations at extracting PCBs from different masonry types after the source (e.g., caulk) has been removed. The solvent-paste is applied directly to the contaminated masonry surface and scraped off after a pre-determined treatment period. Once applied, the lipophilic alcohol in the solvent-paste penetrates the masonry’s open pore spaces, and solubilizes the PCB molecules it encounters along the way. The process of desorbing the PCBs from the inorganic masonry particles and into the applied paste is aided – via capillary action – by the lipophilic alcohol drawing the hydrophobic PCBs toward the paste. Technical challenges include desorbing the stickier spectrum of hydrophobic Aroclors (e.g., 1248, 1254, 1260) added to paints, caulks and adhesives in seasonally cool ( 50°F), wet weather. Since successful commercialization of an alternative PCB treatment technology requires approval from EPA in accordance with the PCB regulations (40 CFR 761), the performance of both solvent-pastes will be evaluated against the regulation’s stringent 1 ppm high occupancy cleanup criterion.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.