School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Environ Sci Technol. 2021 Nov 16;55(22):15446-15455. doi: 10.1021/acs.est.1c04907. Epub 2021 Nov 5.
Microalgae are emerging as next-generation renewable resources for production of sustainable biofuels and high-value bioproducts. Conventional microalgae harvesting methods including centrifugation, filtration, flocculation, and flotation are limited by intensive energy consumption, high capital cost, long treatment time, or the requirement of chemical addition. In this study, we design and fabricate porous superabsorbent polymer (PSAP) beads for self-driven 3D microfiltration of microalgal cultures. The PSAP beads can swell fast in a microalgal suspension with high water absorption capacity. During this process, microalgal cells are excluded outside the beads and successfully concentrated in the residual medium. After treatment, the beads can be easily separated from the microalgal concentrate and reused after dewatering. In one PSAP treatment, a high concentration factor for microalgal cultures up to 13 times can be achieved in 30 min with a harvesting efficiency higher than 90%. Furthermore, microalgal cultures could be concentrated from 0.2 g L to higher than 120 g L with minimal biomass loss through multistage PSAP treatments. Therefore, the use of PSAP beads for microalgae harvesting is fast, effective, and scalable. It does not require any complex instrument or chemical addition. This technique potentially provides an efficient and feasible alternative to obtain high concentrations of functional biomass at a very low cost.
微藻作为生产可持续生物燃料和高价值生物制品的新一代可再生资源正在兴起。传统的微藻收获方法包括离心、过滤、絮凝和浮选等，这些方法受到能源消耗大、资本成本高、处理时间长或需要添加化学物质等限制。在本研究中，我们设计并制造了多孔超吸水性聚合物（PSAP）珠，用于微藻培养物的自驱动 3D 微滤。PSAP 珠在高水吸收能力的微藻悬浮液中能够快速膨胀。在这个过程中，微藻细胞被排斥在珠体之外，并成功地浓缩在残留的培养基中。处理后，珠体可以很容易地与微藻浓缩物分离，并在脱水后重复使用。在一次 PSAP 处理中，在 30 分钟内可以实现高达 13 倍的微藻培养物浓缩，收获效率高于 90%。此外，通过多步 PSAP 处理，可以将微藻培养物从 0.2 g/L 浓缩到 120 g/L 以上，生物量损失最小。因此，PSAP 珠用于微藻收获快速、有效且可扩展。它不需要任何复杂的仪器或添加化学物质。这项技术为以非常低的成本获得高浓度功能生物质提供了一种高效可行的替代方法。
