Adrah Kelvin, Pathiraja Gayani, Rathnayake Hemali
Department of Nanoscience, Joint School of Nanoscience & Nanoengineering, University of North Carolina at Greensboro, 1907 East Gate City Blvd, Greensboro, North Carolina 27401, United States.
ACS Omega. 2024 Dec 19;10(1):239-260. doi: 10.1021/acsomega.4c05152. eCollection 2025 Jan 14.
An innovative biosorbent-based water remediation unit could reduce the demand for freshwater while protecting the surface and groundwater sources by using saline water resources, such as brine, brackish water, and seawater for irrigation. Herein, for the first time, we introduce a simple, rapid, and cost-effective iron(III)-tannate biosorbent-based technology, which functions as a stand-alone fixed-bed filter system for the treatment of salinity, heavy-metal contaminants, and pathogens present in a variety of water resources. Our approach presents a streamlined, cost-efficient, energy-saving, and sustainable avenue for water treatment, distinct from current adsorption desalination or conventional membrane techniques supplemented with chemical and UV treatments for disinfection. The proof of feasibility for effective treatment of heavy metals, adsorption desalination, and cleansing of pathogens is demonstrated using synthetic water, brine, and field-collected seawater. The adsorption equilibrium and adsorption kinetic isotherm models, and mass transfer diffusion models confirmed the sorbent's function for sieving heavy-metal ions-silver (Ag), cadmium (Cd), and lead (Pb)-from water. The maximum adsorption capacities ( ) of the sorbent for Ag, Cd, and Pb reach 96.25, 66.54, and 133.83 mg/g at neutral pH. The sorbent's affinity for heavy-metal-ion adsorption significantly increased, yielding of 116.57 mg/g for Ag, 104.04 mg/g for Cd, and 165.66 mg/g for Pb, at pH 9, respectively, due to the sorbent's amphoteric nature. The pristine sorbents exhibit exceptional adsorption desalination efficacy (>70%) for removing salinity from brine and seawater, promoting heterogeneous adsorption. Fe(III)-TA's ability to disinfect seawater, with 67% efficacy over a very short contact time (∼15 min), confirms its remarkable antimicrobial properties for contact active mode pathogens cleansing. By preventing the release of salts, heavy-metal contaminants, and pathogens into the environment, our results proved that this novel multiplex biobased sorbent approach directly contributes to the water quality of surface and groundwater resources.
一种创新的基于生物吸附剂的水修复装置可以通过利用盐水、微咸水和海水等咸水资源进行灌溉，从而减少对淡水的需求，同时保护地表水和地下水源。在此，我们首次引入了一种简单、快速且经济高效的基于铁（III）-单宁酸盐生物吸附剂的技术，该技术作为一个独立的固定床过滤系统，用于处理各种水资源中存在的盐分、重金属污染物和病原体。我们的方法为水处理提供了一条简化、经济高效、节能且可持续的途径，与当前的吸附脱盐或补充化学和紫外线处理进行消毒的传统膜技术不同。使用合成水、盐水和现场采集的海水证明了有效处理重金属、吸附脱盐和清除病原体的可行性。吸附平衡和吸附动力学等温线模型以及传质扩散模型证实了吸附剂从水中筛分重金属离子——银（Ag）、镉（Cd）和铅（Pb）——的功能。在中性pH值下，吸附剂对Ag、Cd和Pb的最大吸附容量分别达到96.25、66.54和133.83 mg/g。由于吸附剂的两性性质，在pH值为9时，吸附剂对重金属离子吸附的亲和力显著增加，Ag的吸附容量为116.57 mg/g，Cd为104.04 mg/g，Pb为165.66 mg/g。原始吸附剂在去除盐水和海水中的盐分方面表现出出色的吸附脱盐效果（>70%），促进了非均相吸附。Fe（III）-TA在非常短的接触时间（约15分钟）内对海水进行消毒的效率为67%，证实了其对接触活性模式病原体清除具有显著的抗菌性能。通过防止盐、重金属污染物和病原体释放到环境中，我们的结果证明了这种新型的基于生物的多重吸附剂方法直接有助于地表水和地下水资源的水质。
