Company: SQM
Filing Date: 2025-04-24
Form Type: 20-F
Source: 0000909037-25-000020
Chunk: 72

Company: CHEMICAL & MINING CO OF CHILE INC
Filing Date: 2025-04-24
Form: 20-F
Item: Item 4
Chunk 72
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 hydroxide brine is stored in ponds. The brine is then evaporated in a multi-effect evaporator and crystallized to produce lithium hydroxide which is then dried and packaged for shipment to customers.
Our lithium hydroxide production quality assurance program has been certified by TÜV-Rheinland under ISO 9001:2015 since September 2018.
Lithium Sulfate
During the brine concentration process and if the chemistries are favorable, it is possible to obtain lithium sulfate as additional raw material. This salt mainly precipitates in the potassium carnallite and bischofite stages. 
After collection, the lithium sulfate is treated in the MOP H II plant through crushing, flotation and filtration processes, obtaining wet lithium sulfate as an intermediate product. In addition, salts with high potassium content are obtained as a by-product of the process, which are treated in the adjacent SOP-H plant, allowing additional potassium chloride to be obtained.
The wet lithium sulfate is then treated at the SOP S/C plant producing dry lithium sulfate as a finished product, which is currently sent to our refining plant and different tolling facilities in China to be converted into lithium hydroxide and/or lithium carbonate.
Lithium Hydroxide (from Lithium Sulfate)
Our lithium hydroxide operations in China began at the beginning of 2023, with a design annual capacity of 20,000 metric tons. The production of lithium hydroxide monohydrate from lithium sulfate begins with a purification stage of the raw material for its subsequent transformation to lithium carbonate, which is subsequently converted into high-purity lithium hydroxide through crystallization, drying, cooling and packaging stages. Impurities from the process are eliminated in a form of mixed salts, avoiding liquid waste in the plant. Sodium sulfate is generated as a by-product, which is dried and packaged for sale.
Additionally, we have tolling contracts with tolling facilities in China for the refining of lithium sulfate with an additional annual capacity of 20,000 metric tons allowing the production of lithium hydroxide and/or lithium carbonate.
Potassium Chloride
We use potassium chloride derived from the Salar de Atacama brines in the production of potassium nitrate. Production of our own supplies of potassium chloride provides us with substantial raw material cost savings. We also sell potassium chloride to third parties, primarily as a commodity fertilizer.
To produce potassium chloride, brines from the Salar de Atacama are sent to the first evaporation stage