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In recent years, the pressurized leaching process for zinc concentrate has seen new advancements in the following areas: Shi Wei and others applied a new catalytic oxidation acid leaching process using nitric acid as a catalyst to the leaching of zinc sulfide concentrate. This process is simple to operate, requires minimal equipment, has low investment costs, and is suitable for small-scale production. Jiang Kaixi, Wang Haibei, and others from the Beijing Research Institute of Mining and Metallurgy proposed using hot acid leachate to leach zinc concentrate; the zinc leaching rate was greater than 96%, the iron content in the leachate was below 2 g/L, and the conversion rate of elemental sulfur was greater than 90%. Organically combine pressurized leaching with atmospheric pressure leaching to achieve both iron removal and capacity expansion. Chalkley and colleagues developed a new process that combines two-stage counter-current pressure leaching with reduction leaching, along with hematite precipitation. This process is adaptable to a wide range of feedstocks, achieves high recovery rates for zinc, lead, and silver, and produces hematite products that are environmentally friendly and suitable for export. Jones proposed a new process that combines pressurized leaching with solvent extraction, whereby the pressurized leachate is used for copper and zinc extraction to recover these metals, while the zinc-depleted raffinate is returned to the zinc concentrate pressurized leaching system. This process not only makes full use of the iron in the raffinate to effectively treat it, but also achieves a high leaching rate for zinc. Jones further developed a process for recovering the precious metal silver from pressurized leaching residues. Research on the pressurized acid leaching process for zinc concentrate has been carried out in China since the mid-1980s. The Beijing Research Institute of Mining and Metallurgy conducted experiments on the pressure leaching of zinc concentrate using pressure reactors of 2L, 10L, and 300L capacities. In recent years, research on the pressurized leaching process for sphalerite has been carried out in China one after another. In the study by Wang Yufang et al. on the pressure leaching of sphalerite at medium temperature (388 K) using a sulfur-free dispersant, the zinc leaching rate was greater than 96%, and the iron content in the leachate was no more than 2.5 g/L. After completing semi-industrial trials, Yunnan Metallurgical Group has built and put into operation the first industrial plant of its kind in China in Yunnan.