Thallium is a highly toxic rare metal element, its toxicity far surpassing that of heavy metals like Hg, As, Pb, Cd, and Cu. It primarily affects the conduction of nerve impulses by competing with K+ within the human body. Thallium contamination of water bodies poses significant harm to public health. In light of thallium's toxicity, the United States Environmental Protection Agency has listed it as one of the thirteen priority monitored heavy metal pollutants. China's "Twelfth Five-Year Plan for Comprehensive Prevention and Control of Heavy Metal Pollution" also includes thallium as one of the key heavy metal pollutants to be controlled.

In nature, thallium often occurs as a trace element in oxidized minerals such as feldspar, mica, and jarosite, as well as in sulfide minerals like pyrite, galena, and chalcopyrite. During the mining, beneficiation, and smelting processes of these ores, a large amount of thallium-containing wastewater is produced. Due to its strong mobility, thallium in wastewater easily enters environmental water bodies, posing severe health risks through drinking water and the food chain. The lead-zinc mining and smelting industry is a significant source of thallium environmental pollution, with thallium accumulation in the acidic wastewater from smelting processes reaching up to 70-80 mg/L. In recent years, as China continues to exploit its abundant thallium-containing mineral resources, waterbody thallium pollution has shown an intensifying trend, posing serious threats to human and environmental health. Therefore, the treatment and purification of thallium-containing wastewater is urgently needed.

Many methods have been developed for removing thallium from industrial wastewater. The editors at Zhongxiang Chun Tian Environmental Protection Technology will introduce the thallium removal methods to you: such as chemical precipitation, biological adsorption, and metal oxide adsorption methods, among which the most commonly used method is to oxidize thallium from soluble Tl(I) to Tl(III) and form a precipitate for removal (CN201510802733.1 - A method for treating wastewater containing thallium and ammonia nitrogen by combining pre-oxidation and coagulation precipitation, CN201510106618.0 - A deep treatment method for thallium-containing wastewater, CN201510076851.9 - A deep purification process for thallium-containing wastewater). Oxidizing agents include double oxygen water (CN201510468124.7 - A new method for efficiently removing thallium and arsenic from smelting wastewater simultaneously, CN201510207306.9 - A method for removing trace thallium from sewage), ferric perchlorate (CN201410186418.6 - A method for removing trace thallium from water), potassium permanganate (CN201310609199.3 - A method for removing cadmium and thallium simultaneously from raw water), etc. There are also methods that directly use hydrated manganese dioxide (CN201510106618.0 - A deep treatment method for thallium-containing wastewater) or nanoscale manganese dioxide (CN201110057640.2 - A method for deep purification of trace thallium in water using polymer-based nanoscale manganese dioxide) to oxidize and adsorb thallium from the wastewater.

The Shaoqian large smelting plant, previously struggling to meet standards for heavy metal "thallium" in its wastewater, has now been successfully treated with a heavy metal nanomaterial 3# treatment agent from Zhongxiang Spring Environmental Protection Technology Co., Ltd., and has been operating normally with compliant emissions.