Inorganic Chemicals Industry ›› 2026, Vol. 58 ›› Issue (2): 45-52.doi: 10.19964/j.issn.1006-4990.2025-0022

• Research & Development • Previous Articles     Next Articles

Study on leaching transformation characteristics of potassium salts from low-grade sulfate-type sedimentary salt deposits

MEI Xincong1(), YAO Mobai2, SUN Zhe3, ZHANG Yingshuang1, WANG Xueying1(), HUANG Xueli1(), WANG Xuefeng1   

  1. 1.Key Laboratory of Xinjiang Coal Clean Conversion and Chemical Process,College of Chemistry and Chemical Engineering,Xinjiang University,Urumqi 830017,China
    2.SDIC Xinjiang Luobupo Potash Co. ,Ltd. ,Hami ;839000,China
    3.Xinjiang Nonferrous Metals Research Institute Co. ,Ltd. ,Urumqi 830054,China
  • Received:2025-01-15 Online:2026-02-10 Published:2025-08-12
  • Contact: WANG Xueying, HUANG Xueli E-mail:xcmei9801@163.com;wangxy229@xju.edu.cn;xuelih@163.com

Abstract:

The Lop Nur region hosts certain reserves of sulfate-type sedimentary salt deposits.Although its potassium content is not high,it still possesses value for development and utilization.Crystal structure analysis was conducted on this sulfate-type sedimentary salt deposits,along with experimental studies on potassium extraction via leaching.The results indicated that the ore was primarily composed of NaCl and contained substantial amounts of sulfates and their double salts,such as magnesium sulfate,mirabilite,gypsum,polyhalite,kainite,and minor carnallite.The content ranges were 1.9% to 5.3% for K⁺,4.2% to 6.9% for Mg²⁺,and 17.1% to 30.2% for SO₄²⁻(all by mass).Leaching experiments employing raw brine from Lop Nur,process brines from different stages of potassium sulfate production using Lop Nur salt lake brine,various saturated brines,and deionized water revealed that the raw Lop Nur brine was the superior leaching agent for potassium extraction from this salt deposits.A high sulfate ion content in the leaching agent favored K⁺ dissolution.Among the leaching parameters,the liquid-to-solid ratio exerted the most significant influence on the potassium leaching rate,followed by leaching temperature,with leaching time having the least effect.The optimal leaching conditions using raw Lop Nur brine were liquid-to-solid ratio of 2.0,temperature of 25 ℃,and duration of 45 min.Under these conditions,the K⁺ leaching rate reached 87.6%,and the K⁺ content in the leachate was increased to 2.53 times that of the original brine.These findings provided theoretical support and data for the development and utilization of potassium from sulfate-type sedimentary salt deposits.

Key words: Lop Nur, sulfate-type sedimentary salt deposits, leading transformation, potassium leaching rate

CLC Number: