Quantification of Oxygen Nanobubbles in Particulate Matters andPotential Applications in Remediation of Anaerobic Environment

摘要

Interfacial nanobubbles can exist on varioushydrophobic and hydrophilic material interfaces. There arediverse applications for oxygen nanobubbles, which are closelyrelated to their content and long-term stability. However, itremains challenging to determine the amount of nanobubblesloaded in a porous material. In this study, a novel method wasused to quantify the total amount of oxygen nanobubbles loadedonto irregular particulate materials. Different materials wereevaluated and their oxygen-loading capacities were found to beas follows: activated carbon (AC) > zeolite > biochar >diatomite > coal ash > clay. Significant differences in oxygenloading capacities were mainly ascribed to differences in thespecific surface area and hydrophobic/hydrophilic properties ofthe materials. The total oxygen loading on AC achieved usingthe high pressure loading method was higher than that achieved by the temperature variation method. This new quantitativemethod provides the possibility for the manipulation of oxygen nanobubble materials in practical applications and it isanticipated to be an important supplement to the existing methods of characterizing interfacial oxygen nanobubbles. Our resultsdemonstrate that materials containing oxygen nanobubbles can significantly increase the dissolved oxygen and oxidationreduction potential in anaerobic systems. With the addition of oxygen-loaded materials (such as AC), the survival time ofzebrafish was prolonged up to 20 h in a deoxygenated water system, and the germination rate of Vallisneria spiralis was alsoincreased from 27 to 73% in an anaerobic sediment.