Siru Chen,Kaixin Lin,Aiqiang Pan,Tsz Chung Ho,Yihao Zhu,Chi Yan Tso
All-day passive radiative cooling is a promising cooling technique achieves cooling without any energy input, thereby attracting tremendous attention. Most of the studies focus on building applications, but there remains a lack of information on other potential applications of radiative cooling systems. Herein, we report an application of a polymeric passive radiative cooling coating (PRCC) on the exterior surface of chemical storage tanks, which is often overlooked but exhibits great potential to efficiently control the evaporative loss of the chemicals. The PRCC exhibits strong solar reflectivity (96.2%) and emissivity (95%) in the mid-infrared wavelength range. According to the results of an outdoor test on a small-scale chemical storage container, the PRCC achieves 81.4%, 54.1%, and 19.8% of chemicals saved compared with a raw container, container painted with commercial white paint (CWP), and the shaded raw container, respectively. A numerical simulation is also conducted to estimate the chemical standing loss from an industrial large-scale chemical storage tank. It is found that the PRCC can achieve a saving of over 50% of the chemical compared with commercial white paint for a chemical storage tank, showing a promising potential to be applied on chemical storage systems.
Jinhua Zhang,Si Xiong,Jingran Wang,Yue’e Ni,Changming Ke
Phase pure and nano-sized hafnium diboride (HfB 2 ) fine powder was prepared via a novel sustainable silicothermic route at 1100°C from inexpensive raw materials HfO 2 , Na 2 B 4 O 7 and Si. By introducing sodium oxysalts as source of Na 2 O into the batch mixtures, the SiO 2 / Na 2 O modulus in the melt were reduced from 5:1 to 2:1, and the original water-insoluble byproduct SiO 2 was taken by the melt at test temperature and converted into water soluble sodium silicate (Na 2 Si 2 O 5 ) which was easily removed from the reacted mass via simple hot water washing. Consequently, the aqua sodium silicate could be readily recycled and used as a precursor for preparing many other valuable materials due to absence of foreign salts (eg halides, especially in the molten salt-assisted synthesis process) in the synthesis process, and the relevant environmental concerns could be alleviated. Using excessive amount of 20 wt% Si and 15 wt% Na 2 B 4 O 7 as compensation for the evaporation loss of silicon, in the form of SiO (g), and B 2 O 3 in the reduction process, a high reaction extent was achieved and HfO 2 and Na 2 B 4 O 7 were completely converted into HfB 2 at 1100°C.