Effect of nano-silica and graphene oxide on properties of phosphogypsum
ZHOU Xiang, et al
Chengdu Institute of Product Quality Inspection Co. LTD., National Building Materials Product Quality Inspection and Testing Center (Sichuan), Chengdu 610100, Sichuan, China
Abstract：To achieve the high-quality development of building materials of phosphogypsum, nano-silica and graphene oxide(GO)were used as modifiers to improve the physical properties of phosphogypsum.It is showed that the working performance of phosphogypsum were influenced by nano-silica and GO. Setting time of phosphogypsum were extended by nano-silica, but on the contrary to GO. And the setting time shorter with the dosage of nano-silica and GO higher. Nano-silica can effectively improved the fluidity of phosphogypsum, while GO significantly reduced the fluidity of phosphogypsum. The higher the dosage of GO, the greater the loss of fluidity of phosphogypsum. Compared to nano-silica, the dry strength and water resistance of phosphogypsum were more effectively improved by GO. The dry strength of phosphogypsum was the best when the nano-silica and GO contents were 1.5% and 0.2% respectively. The water absorption of phosphogypsum decreased first and then increased with the increased of the nano-silica and GO, while the softening coefficient phosphogypsum changed conversely. Nano-silica(<3.0%) made a positive effect on the heat release rate of phosphogypsum in early hydration.The hydration heat of phosphogypsum can be significantly increased when the content of GO was 0.2%, but the hydration heat of phosphogypsum was not significantly affected by insufficient or too high content of GO
2024, Vol. 0 
