Wang Lei, Miao Xiaojun, Ali Jafar, Lyu Tao, Pan Gang
Department of Environmental Nanotechnology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, P. R. China.
Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
ACS Omega. 2018 Sep 30;3(9):10624-10630. doi: 10.1021/acsomega.8b00784. Epub 2018 Sep 5.
Interfacial nanobubbles can exist on various hydrophobic and hydrophilic material interfaces. There are diverse applications for oxygen nanobubbles, which are closely related to their content and long-term stability. However, it remains challenging to determine the amount of nanobubbles loaded in a porous material. In this study, a novel method was used to quantify the total amount of oxygen nanobubbles loaded onto irregular particulate materials. Different materials were evaluated and their oxygen-loading capacities were found to be as follows: activated carbon (AC) > zeolite > biochar > diatomite > coal ash > clay. Significant differences in oxygen-loading capacities were mainly ascribed to differences in the specific surface area and hydrophobic/hydrophilic properties of the materials. The total oxygen loading on AC achieved using the high pressure loading method was higher than that achieved by the temperature variation method. This new quantitative method provides the possibility for the manipulation of oxygen nanobubble materials in practical applications and it is anticipated to be an important supplement to the existing methods of characterizing interfacial oxygen nanobubbles. Our results demonstrate that materials containing oxygen nanobubbles can significantly increase the dissolved oxygen and oxidation reduction potential in anaerobic systems. With the addition of oxygen-loaded materials (such as AC), the survival time of zebrafish was prolonged up to 20 h in a deoxygenated water system, and the germination rate of was also increased from 27 to 73% in an anaerobic sediment.
界面纳米气泡可存在于各种疏水和亲水材料界面上。氧纳米气泡有多种应用，这与其含量和长期稳定性密切相关。然而，确定多孔材料中负载的纳米气泡数量仍然具有挑战性。在本研究中，采用了一种新方法来量化负载在不规则颗粒材料上的氧纳米气泡总量。对不同材料进行了评估，发现它们的载氧能力如下：活性炭（AC）>沸石>生物炭>硅藻土>粉煤灰>粘土。载氧能力的显著差异主要归因于材料比表面积和疏水/亲水性质的差异。采用高压加载法在AC上实现的总氧负载高于通过温度变化法实现的总氧负载。这种新的定量方法为在实际应用中操控氧纳米气泡材料提供了可能性，预计将成为现有表征界面氧纳米气泡方法的重要补充。我们的结果表明，含有氧纳米气泡的材料可显著提高厌氧系统中的溶解氧和氧化还原电位。在脱氧水系统中，添加载氧材料（如AC）后，斑马鱼的存活时间延长至20小时，在厌氧沉积物中，（此处原文缺失内容）的发芽率也从27%提高到73%。
