摘要
采用热化学活化和化学活化协同处理磷钾伴生矿酸浸硅渣,以提高硅渣中硅的活化程度,采用响应面法优化了硅活化条件,研究了硅活化过程的热力学与动力学,并通过XRD、FTIR、SEM等手段对活化前后硅渣进行了表征,揭示了硅活化机理。结果表明,最佳活化条件为:浸出温度126℃、浸出时间78.11 min、NaOH溶液浓度1.06 mol·L^(-1)、NaOH溶液用量49.67 mL、焙烧温度446℃、焙烧时间120 min、助剂比(助熔剂Na_(2) CO_(3)与硅渣的质量比)0.327∶1,在此条件下,硅浸出率为93.54%;硅渣焙烧和浸出过程可分别采用三维界面反应模型和固体产物层扩散模型描述;焙烧破坏了硅渣的晶体结构,促使部分晶态SiO_(2)转化为非晶态SiO_(2),且焙烧后硅渣呈疏松多孔结构,有利于后续SiO_(2)与NaOH溶液的浸出反应。
We treated the acid leaching silicon slag of phosphorus-potassium associated ore by the combined process of thermal chemical activation and chemical activation to enhance the activation degree of silicon in the silicon slag.Moreover,we optimized the silicon activation conditions by response surface methodologies,and studied the thermodynamics and kinetics of the silicon activation process.Furthermore,we characterized the silicon slag before and after activation by XRD,FTIR,and SEM,and revealed the silicon activation mechanism.The results show that the optimal activation conditions are as follows:the leaching temperature of 126℃,the leaching time of 78.11 min,the NaOH solution concentration of 1.06 mol·L^(-1),the NaOH solution dosage of 49.67 mL,the calcination temperature of 446℃,the calcination time of 120 min,and the flux addition ratio(the mass ratio of Na_(2) CO_(3) to silicon slag)of 0.327∶1.Under above conditions,the silicon leaching rate is 93.54%.The calcination and leaching processes of silicon slag can be described by the three-dimensional interface reaction model and the solid product layer diffusion model,respectively.Calcination destroys the crystalline structure of the silicon slag,promoting the transformation of part of the crystalline SiO_(2) into amorphous SiO_(2).In addition,the silicon slag after calcination has a loose and porous structure,which is conducive to the subsequent leaching reaction of SiO_(2) with NaOH solution.
作者
王晓东
何东升
党元林
马家玉
杨平
汪铁林
WANG Xiaodong;HE Dongsheng;DANG Yuanlin;MA Jiayu;YANG Ping;WANG Tielin(School of Chemical Engineering and Pharmacy,Wuhan Institute of Technology,Wuhan 430205,China;Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education,Wuhan Institute of Technology,Wuhan 430074,China;Xingfa School of Mining Engineering,Wuhan Institute of Technology,Wuhan 430074,China;Sichuan Yongxiang Resin Co.,Ltd.,Leshan 614800,China)
出处
《化学与生物工程》
北大核心
2025年第11期18-27,共10页
Chemistry & Bioengineering
基金
国家重点研发计划“固废资源化”专项(2019YFC1905803)
湖北省重点研发计划项目(2022BCA086)
云南省磷资源技术创新中心项目(202305AK340002-4)
教育部磷资源综合利用与清洁加工工程研究中心开放课题基金项目(2024CUCPPR03)
武汉工程大学科学研究基金项目(K202002)。
关键词
磷钾伴生矿
硅渣
活化
响应面法
焙烧
动力学
phosphorus-potassium associated ore
silicon slag
activation
response surface methodology
calcination
kinetics
