管学茂, 张紫涵, 刘松辉,等.钛石膏在酸溶液中的除铁与相变规律研究[J].河南理工大学学报（自然科学版）,2025,44(1):193-200.

GUAN X M, ZHANG Z H, LIU S H, et al. Study on iron removal and phase transition behavior of titanium gypsum in acidic solution[J]. Journal of Henan Polytechnic University(Natural Science) , 2025, 44(1): 193-200.

钛石膏在酸溶液中的除铁与相变规律研究

管学茂, 张紫涵, 刘松辉, 朱建平

河南理工大学 材料科学与工程学院，河南 焦作 454000

摘要: 目的 为了解决钛石膏中的杂质问题，探讨常压下石膏的相变规律， 方法 以工业固废钛石膏为原料，以酸浸法处理，采用X射线衍射仪和X射线荧光光谱，分别测定反应产物的物相组成和化学成分，分析产物的物相，同时定量分析产物的除铁率和石膏含量进行除铁效果表征，通过对不同条件处理原料、反应过程中酸的种类和浓度、反应温度和时间等条件探索，钛石膏的除铁效果和石膏的相变规律。采用超景深显微镜探索原料和产物的微观形貌，同步验证酸溶液中钛石膏的除铁效果。 结果 相较于盐酸、草酸和硝酸，硫酸的除铁效果最好且无其它杂质生成；随着酸浓度的提高，硫酸溶液中发生了二水石膏-硬石膏物相转化，在硝酸溶液和盐酸溶液中，发生了二水石膏-半水石膏物相转化，草酸溶液中最终生成草酸钙；在硫酸溶液反应中，提高提高硫酸浓度、反应温度和反应时间，均可促进二水石膏-硬石膏物相转化；对工业固废钛石膏原料进行处理时，未干燥研磨处理的原料，不影响物相的转化，由此可减少原料的操作步骤和能源消耗，节约钛石膏材料的预处理成本。 结论 研究结果可有效解决钛石膏中杂质问题，减少了实验和使用过程中的能源消耗，降低成本，同时可得出二水石膏-半水石膏-硬石膏之间的物相转化规律，补充石膏性能变化规律，扩大石膏资源再利用方向。

关键词:钛石膏;除铁效果;相变规律;酸溶液;酸浸法

doi: 10.16186/j.cnki.1673-9787.2023030002

基金项目:国家自然科学基金资助项目（U1905216）

收稿日期:2023/03/01

修回日期:2023/05/29

出版日期:2025/01/02

Study on iron removal and phase transition behavior of titanium gypsum in acidic solution

GUAN Xuemao, ZHANG Zihan, LIU Songhui, ZHU Jianping

School of Materials Science and Engineering， Henan Polytechnic University， Jiaozuo 454000， Henan， China

Abstract: Objectives This study aims to address the issue of impurities in titanium gypsum and investigate the phase transformation behavior of gypsum under atmospheric pressure. Methods Industrial solid waste titanium gypsum was used as the raw material and treated with an acidic solution leaching method. The phase composition and chemical composition of the reaction products were analyzed using X-ray diffraction （XRD） and X-ray fluorescence （XRF）， respectively. The phases of the products were identified， and the iron removal rate and gypsum content were quantitatively evaluated to characterize the efficiency of iron removal. The effects of various factors， including raw material preparation， the type and concentration of acidic solutions， reaction temperature， and reaction time， were investigated to determine the iron removal efficiency and the phase transformation behavior of titanium gypsum. An ultra-depth-of-field microscope was employed to observe the microstructure of raw materials and products， thereby verifying the iron removal effect of titanium gypsum in acidic solutions. Results Sulfuric acid demonstrated the best iron removal performance compared to hydrochloric acid， oxalic acid， and nitric acid， without generating other impurities. With increasing acid concentration， the phase transformation from gypsum dihydrate to anhydrite occurred in sulfuric acid solutions， while the transformation from gypsum dihydrate to hemihydrate gypsum was observed in both nitric acid and hydrochloric acid solutions. In oxalic acid solutions， calcium oxalate was ultimately formed. For reactions in sulfuric acid， higher acid concentration， reaction temperature， and reaction time promoted the transformation of gypsum dihydrate to anhydrite. When untreated （unmilled and undried） raw materials were used， the phase transformation was not affected， reducing the operational steps and energy consumption in raw material preparation and thereby lowering the pretreatment cost of titanium gypsum. Conclusions This study provides an effective method to remove impurities from titanium gypsum， reduce energy consumption and costs， and elucidate the phase transformation pathways between gypsum dihydrate， hemihydrate gypsum， and anhydrite. The findings supplement the understanding of gypsum performance variations and broaden the potential applications of gypsum resource reutilization.

Key words: titanium gypsum; iron removal efficiency; phase transformation behavior; acidic solution; anhydirte