Preparation And Performance Study Of Copper Slag-based Iron-based Phosphate Chemical Bonding Materials

Copper slag is produced during pyrometallurgical production of copper from copper ores.A great amount of copper slag is produced every year with the increasing demand for copper.The accumulation of copper slag occupied a large amount of land and damaged the surrounding environment.Making comprehensive and efficient use of copper slag in large quantities becomes the urgent problem to be solved.I n the current research,a special iron phosphate chemically b onded ceramics?IPCBC?with high strength was prepared by the chemical reaction between copper slag and acid phosphate,which have advantageous properties including rapid setting and hardening,low water demand and high early strength??1?The technological parameter of copper slag-based iron phosphate chemically bonded ceramics was determined by experiment:using ammonium dihydrogen phosphate as phosphorus source,water-cement ratio was 0.14,CS/ADP was 4.0,the compressive strength of the samples was the highest.The 1d,3d,7d and28d compressive strength reaches 31.7MPa,38.2MPa,41.2MPa and 42.8MPa respectively.The microscopic structural and reaction product of IPCBC paste were examined by X-ray Diffraction?XRD?,scanning electronic microscopic-energy dispersive spectrometer?SEM-EDS?and fourier transform infrared spectrometer?FTIR?,the products of IPCBC are mainly Fe PO ₄,Fe H₂P₃O₁₀ and NH₄Fe₂?PO₄?₂OH·2H₂O and other hydration products.The reaction products reprent the matrix that links together the anhydrous grains,which makes the material have a certain strength.?2?the influence of borax,borax acid and sodium triphosphate content on the properties of IPCBC paste were studied.The suitable content of borax,borax acid and sodium triphosphate as a retarding chemical ha d a beneficial effect on setting time and compressive strength.?3?The properties of IPCBC treated with different temperature were studied.The results show that thecompressive strength of ADP-IPCBC decreases sharply at200?,and the strength changes little at 400?⁶00?.When the temperature rised to 800-1200?,The compressive strength of ADP-IPCBC has been enhanced.After exposed 1200?treatment,the strength of ADP-IPCBC reached 111.2MPa.The strength of KDP-IPCBC decreased slowly with the increase of temperature.However,,the KDP-IPCBC samples melts at 1200?,the structure of KDP-IPCBC was destroyed and the strength was lost.?4?The water resistance of ADP-IPCBC was studied.The softening coefficient of samples immersion in water for 48h was 0.63,the water absorption rate was 8.16%.This indicated that ADP-IPCBC has poor water resistance.The effect of fly ash content on the water resistance of ADP-IPCBC was investigated for improve the water resistance of ADP-IPCBC.The results show that the water resistance of ADP-IPCBC can be improved when the content of fly ash is 10%.