钛白废酸浸出赤泥脱碱实验研究与动力学分析

硅酸盐通报 ›› 2020, Vol. 39 ›› Issue (12): 3918-3923.

钛白废酸浸出赤泥脱碱实验研究与动力学分析

朱晓波^1,2, 王涛¹, 李望¹

1.河南理工大学化学化工学院,焦作 454000;
2.武汉科技大学,国家环境保护矿冶资源利用与污染控制重点实验室,武汉 430081

发布日期:2021-02-01
通讯作者: 李望,博士,副教授。E-mail:liwang0805@126.com
作者简介:朱晓波(1985—),男,博士,副教授。主要从事固体废弃物综合利用方面的研究。E-mail:zhuxiaobo0119@126.com
基金资助:
国家自然科学基金(51904097,51804103);河南省高等学校青年骨干教师培养计划(2019GGJS056);国家环境保护矿冶资源利用与污染控制重点实验室开放基金(HB201905)

Experiment and Kinetics of Dealkalization from Red Mud by Leaching with Titanium Dioxide Waste Acid

ZHU Xiaobo^1,2, WANG Tao¹, LI Wang¹

1. College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454000, China;
2. State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control, Wuhan University of Science and Technology, Wuhan 430081, China

Published:2021-02-01

摘要/Abstract

摘要： 依据赤泥强碱性和钛白废酸呈酸性的特点,利用钛白废酸浸出赤泥脱碱。考察了搅拌速率、液固比、浸出温度和浸出时间对赤泥脱碱效果的影响,同时对赤泥脱碱过程进行了理论分析和动力学研究。结果表明:在浸出温度为70 ℃,搅拌速率为400 r/min,液固比为5 mL/g和反应时间为60 min的条件下,赤泥脱碱率大于99%,脱碱液pH值为6.2。利用钛白废酸浸出赤泥,赤泥脱碱率高,脱碱渣中铁品位也得到了富集,可以作为提取回收铁的二次矿产资源。钛白废酸能够显著破坏赤泥中钙霞石的晶体结构,使得结构碱几乎全部溶解,脱碱渣中出现硬石膏衍射峰,赤铁矿衍射峰也可明显分辨。该脱碱过程受未反应核收缩模型(USCM)中的内扩散关键步骤控制,线性相关系数大于0.99,脱碱反应速率常数随着温度升高而增加,表观活化能(E_a)为13.12 kJ/mol。

关键词: 脱碱, 动力学, 表观活化能, 浸出, 赤泥, 钛白废酸

Abstract: Red mud is a tailing produced during alumina smelting of bauxite, in which the content of free alkali and structural alkali is high. Titanium white waste acid is the acid waste liquid produced during the production of titanium white powder by vanadium-titanium magnetite, which contains a large amount of sulfuric acid. According to the strong basicity of red mud and the acidity of titanium dioxide waste acid, the dealkalization from red mud by leaching with titanium white waste acid was put forward. The effect of stirring rate, liquid to solid ratio, leaching temperature and leaching time on dealkalization rate were investigated. Furthermore, the theoretical analysis and leaching kinetics of the process of red mud demineralization were studied with X-ray diffraction (XRD) and the unreacted shrinking core model (USCM). The results show that the dealkalization rate of red mud is higher than 99% and the pH value of the leaching solution is 6.2 under the conditions of leaching temperature of 70 ℃, stirring rate 400 r/min, liquid to solid ratio 5 mL/g and reaction time 60 min. The leaching process of red mud with titanium white waste acid not only achieves the high demineralization rate, but also enriches the iron grade in the demineralization residue, which is used as a secondary mineral resource for extraction and recovery of iron. The titanium white waste acid significantly destroies the crystal structure of cancrinite in the red mud, which results in complete dissolution of the alkali. The diffraction peaks of anhydrite and hematite are obvious in the demineralization residue according to the analysis of XRD. The leaching process is controlled by the internal diffusion by the analysis of leaching kinetics, and the linear correlation coefficient is more than 0.99. The rate constant increases with the increase of temperature and the apparent activation energy (E_a) is 13.12 kJ/mol.

Key words: dealkalization, kinetics, apparent activation energy, leaching, red mud, titanium dioxide waste acid

中图分类号:

TQ170

朱晓波, 王涛, 李望. 钛白废酸浸出赤泥脱碱实验研究与动力学分析[J]. 硅酸盐通报, 2020, 39(12): 3918-3923.

ZHU Xiaobo, WANG Tao, LI Wang. Experiment and Kinetics of Dealkalization from Red Mud by Leaching with Titanium Dioxide Waste Acid[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2020, 39(12): 3918-3923.

参考文献

[1] 固汉念,崔姗姗,王宁,等.赤泥中碱的分布特征与淋滤效果研究[J].无机盐工业,2016,48(2):45-49.
[2] 李彬,张宝华,宁平,等.赤泥资源化利用和安全处理现状与展望[J].化工进展,2018,37(2):714-723.
[3] 张利祥,高一强,黄建洪,等.赤泥资源化综合利用研究进展[J].硅酸盐通报,2020,39(1):144-149.
[4] 张辉,李安林,曾小州,等.以赤泥为助熔剂制备长石质发泡陶瓷[J].硅酸盐通报,2019,38(12):4002-4006.
[5] 王清涛,李森,于华芹,等.利用赤泥制备轻质高强保温装饰一体化建筑材料[J]硅酸盐通报,2018,37(4):1393-1398.
[6] 刘日鑫,张锦洲,高淑娟.拜耳法赤泥对建筑砌块性能的影响分析[J].无机盐工业,2017,49(3):52-54.
[7] 苏泽林,王东波,黄纤晴,等.高碱性拜耳法赤泥碳酸化脱碱及其机理研究[J].硅酸盐通报,2020,39(5):1547-1552.
[8] 吴锋,李辉,杨康.用脱碱赤泥替代生料制备水泥熟料试验研究[J].硅酸盐通报,2016,35(4):1306-1310.
[9] 季文君,刘云,李哲.赤泥及粉煤灰制备免烧砖的工艺探究[J].中北大学学报(自然科学版),2019,40(6):568-572.
[10] 杨艳娟,李建伟,张茂亮,等.改性赤泥免烧砖的制备与放射性屏蔽机理分析[J].矿产保护与利用,2019,39(1):95-99.
[11] 魏红姗,马小娥,管学茂,等.拜耳法赤泥基轻质保温陶瓷的制备[J].硅酸盐通报,2019,38(3):749-751.
[12] Li R B, Zhang T G, Liu Y, et al. Calcification-carbonation method for red mud processing[J]. Journal of Hazardous Materials, 2016, 316: 94-101.
[13] Krivenko P, Kovalchuk O, Pasko A, et al. Development of alkali activated cements and concrete mixture design with high volumes of red mud[J]. Construction and Building Materials, 2017, 151: 819-826.
[14] Zhu X B, Li W, Guan X M. An active dealkalization of red mud with roasting and water leaching[J]. Journal of Hazardous Materials, 2015, 286: 85-91.
[15] 张乐观,王国贞,段璐淳.水洗处理赤泥初步脱碱[J].无机盐工业,2011,43(2):57-58.
[16] 王志,韩敏芳,张以河,等.拜耳法赤泥的湿法碳化脱碱工艺研究[J].硅酸盐通报,2013,32(9):1851-1855.
[17] 王国贞,张乐观,朱泮民,等.赤泥碱回收的初步研究[J].无机盐工业,2011,43(4):55-57.
[18] 罗忠涛,肖宇领,张磊,等.赤泥料浆化多级循环脱碱与碱回收处理工艺[J].济南大学学报,2013,27(2):369-372.
[19] 高波,李佳.四川攀西地区钛白废酸处理现状及综合利用新途径展望[J].广东化工,2019,46(23):69-70.
[20] 杨涛,王志坚,肖劲,等.赤泥和钛白废液中提钪的浸出工艺研究[J].矿冶,2015,24(5):37-40.