Li Xin, Lin Wei, Petrescu Florian Ion Tiberiu, Li Jia, Wang Likui, Zhu Haiyan, Wang Haijun, Shi Gang
Key Laboratory of Synthetic and Biotechnology Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China.
Department of Mechanisms and Robots Theory, National University of Science and Technology Polytechnic Bucharest, 060042 Bucharest, Romania.
Nanomaterials (Basel). 2023 Oct 3;13(19):2696. doi: 10.3390/nano13192696.
Presently, the separation of oil and water through functional membranes inevitably entails either inefficient gravity-driven processes or energy-intensive vacuum pressure mechanisms. This study introduces an innovative photothermal evaporator that uses solar energy to drive oil-water separation while concurrently facilitating the detection of Fe in wastewater. First, by alkali delignification, small holes were formed on the side wall of the large size tubular channel in the direction of wood growth. Subsequently, superhydrophilic SiO nanoparticles were in situ assembled onto the sidewalls of the tubular channels. Finally, carbon quantum dots were deposited by spin-coating on the surface of the evaporator, paralleling the growth direction of the wood. During the photothermal evaporation process, the tubular channels with small holes in the side wall parallel the bulk water, which not only ensures the effective water supply to the photothermal surface but also reduces the heat loss caused by water reflux on the photothermal surface. The superhydrophilic SiO nanoparticles confer both hydrophilic and oleophobic properties to the evaporator, preventing the accumulation of minute oil droplets within the device and achieving sustained and stable oil-water separation over extended periods. These carbon quantum dots exhibit capabilities for both photothermal conversion and fluorescence transmission. This photothermal evaporator achieves an evaporation rate as high as 2.3 kg m h in the oil-water separation process, and it has the ability to detect Fe concentrations in wastewater as low as 10 M.
目前，通过功能膜进行油水分离不可避免地需要低效的重力驱动过程或耗能的真空压力机制。本研究引入了一种创新的光热蒸发器，该蒸发器利用太阳能驱动油水分离，同时便于检测废水中的铁。首先，通过碱法脱木素，在大尺寸管状通道侧壁沿木材生长方向形成小孔。随后，超亲水二氧化硅纳米颗粒原位组装在管状通道的侧壁上。最后，通过旋涂将碳量子点沉积在蒸发器表面，与木材生长方向平行。在光热蒸发过程中，侧壁有小孔的管状通道与大量水平行，这不仅确保了向光热表面有效供水，还减少了光热表面上因水回流而导致的热损失。超亲水二氧化硅纳米颗粒赋予蒸发器亲水性和疏油性，防止微小油滴在装置内积聚，并在较长时间内实现持续稳定的油水分离。这些碳量子点具有光热转换和荧光传输能力。这种光热蒸发器在油水分离过程中的蒸发速率高达2.3 kg m⁻² h⁻¹，并且能够检测低至10⁻⁶ M的废水中铁的浓度。
