Sulfuric Acid Supply Chain - Executive Summary Sulfuric Acid Direct Use Chemical Precursor Chemical h2so4 (liquid) Inputs to Manufacturing Process: Sulfur Oxygen ^ Derivative Water Treatment Chemicals: Aluminum Sulfate Ferric Sulfate Fluorosilicic Acid Ferrous Sulfate Phosphoric Acid Zinc Orthophosphate % of Total Domestic Consumption Attributed to Water Sector: Less than 1% do$ Understanding Chemical Supply Chains Map of Suppliers & Manufacturers Product Family: Sulfur CAS No.: 7664-93-9 Shelf Life: 36 Months RISK OF SUPPLY DISRUPTION (Assessed in 2022) RISK RATING: Low .e,3V-U>w Moder3f vN° '8/> t\ X RISK DRIVERS Competing use in fertilizers accounts for the majority of consumption of domestic pro- duction. Sulfuric acid is com- monly used across many in- dustries. Concerns are primar- ily due to periodic reductions in production of raw material (sulfur). RISK SCORE PARAMETERS Criticality: High. Essential for pH adjust- ment and production of water treat- ment chemicals. Likelihood: Low. Previous significant price increases, but no supply disrup- tions. Vulnerability: Low. Distributed domestic manufacturing and supply. While the majority of domestic manu- facturing is used to produced fertilizer, sulfuric acid is widely available. MANUFACTURING PROCESS Sulfur Oxygen Sulfuric Acid input End Use Water T reatment Applications pH adjustment Ion exchange resin regeneration Water treatment chemical production Other Applications Fertilizer (primarily phosphoric acid production) Chemical manufacturing Ore leaching Petroleum refining DOMESTIC PRODUCTION AND CONSUMPTION, AND INTERNATIONAL TRADE Domestic Manufacturing Locations (2015): 98, distributed throughout the U.S. (^) International Trade (2019) Primary Trading Partner (Imports): Canada Primary Trading Partner (Exports): Canada Domestic Consumption (2019): 25,596 M kg ¦ Domestic Production (22,845 M kg) ¦ Imports for Consumption (2,970 M kg) ¦ Export of Domestic Production (220 M kg) &EPA ------- Sulfuric Acid Supply Chain - Full Profile Product Description Sulfuric acid (H2S04) is an inorganic, strong acid that is widely used for pH adjustment. It is one of the most widely produced chemicals in the world, and is a key input in the production of phosphoric acid. The primary manufacturing process in the U.S. is requires elemental sulfur. The majority of sulfuric acid manufactured in the U.S. is used in fertilizer formulations. Use in Water Treatment Sulfuric acid widely is used in water treatment for pH adjustment, and can also be used to regenerate ion exchange resin. Use as a Precursor to Other Water Treatment Chemicals Sulfuric acid is used to manufacture aluminum sulfate, ferrous and ferric sulfate, fluorosilicic acid, phosphoric acid, and zinc orthophosphate. Other Applications Sulfuric acid has a wide range of applications, and is used directly or indirectly in many industries. The largest single use of sulfuric acid is for the production of phosphoric acid for use in fertilizer. Other uses include industrial chemical manufacturing, extraction of metals from ores, oil refining, pickling and descaling steel, battery acid, wood pulping, and detergent manufacturing (ATSDR, 1998; The Mosaic Company, 2021; The Sulphur Institute, 2018). Primary Industrial Consumers The use of sulfuric acid for phosphate fertilizer manufacturing accounts for the majority of domestic consumption, historically estimated to range between 60-75% of domestic sulfuric acid consumption. Other significant uses are industrial and agricultural chemical manufacturing, ore leaching, and petroleum refining accounting for a combined 35% (McCoy, 2008; NCBI, 2022). Direct use in water treatment is a small percent (< 1%) of the domestic market. Manufacturing, Transport, & Storage Manufacturing Process A significant quantity of sulfuric acid produced in the U.S. starts with molten sulfur or less commonly prilled (pelletized) sulfur. Other production methods include acid regeneration and smelter gas recovery. The most common sulfuric acid manufacturing process proceeds in several steps, outlined in Figure 1. Molten sulfur is oxidized in the presence of dry air (often an oxygen-enriched air) to produce sulfur dioxide, which is cooled for introduction to the converter system. In the presence of a catalyst, sulfur dioxide is converted to sulfur trioxide, and the process gas is moved to an absorption step where sulfur trioxide is absorbed in sulfuric acid to form oleum (sulfur trioxide in sulfuric acid). The oleum, which is much more soluble in water than sulfur trioxide, is cooled and reacted with water to produce concentrated sulfuric acid. EPA 817-F-22-052 | December 2022 f/EPA ------- Sulfuric Acid Supply Chain - Full Profile Step 1 Sulfur + Oxygen > Sulfur Dioxide S + O2 ^ SO2 Step 2 Sulfur Dioxide + Oxygen > Sulfur Trioxide 2S02 + 02 -> 2S03 Step 3 Sulfur Trioxide + Sulfuric Acid > Oleum SO3 + H2SO4 ^ H2S2O7 Step 4 Oleum + Water > Sulfuric Acid H2S2O7 + H20 -> 2H2SO4 Figure 1. Chemical Equation for the Reaction to Manufacture Sulfuric Acid Sulfuric acid can also be produced as a byproduct of smelting mineral ores containing sulfur. Roasting of metal sulfides to obtain the metal releases sulfur in the form of sulfur dioxide. Further metal processing, including leaching, requires sulfuric acid, which can be produced from the sulfur dioxide (The Sulphur Institute, 2018). Spent sulfuric acid may be reclaimed from petroleum refining, steel pickling, and chemical processing and further processed for resale (USGS, 2022). Product Transport Sulfuric acid is typically sold as a liquid in a range of concentrations, in bulk quantities and primarily delivered by specialized railcars to suppliers who repackage and sell the product directly to customers. Transport of sulfuric acid must adhere to the appropriate methods and regulations related to its status as a highly corrosive substance. Sulfuric acid produced by regeneration plants and smelting often requires transport to manufacturing or refining sites (The Sulphur Institute, 2018). Storage and Shelf Life Sulfuric acid should be stored in corrosion-resistant vessels in a cool place away from direct sunlight. When stored properly, sulfuric acid can have a shelf life of 36 months, depending on concentration and size of storage container (CORECFIEM, 2021; The Sulphur Institute, 2018). Domestic Production & Consumption Domestic Production Production data was collected from the EPA Toxic Substances Control Act (TSCA) Chemical Data Reporting (CDR), while trade data was collected from the U.S. International Trade Commission (USITC) Dataweb, as characterized in Table 1. Both production and trade data are specific to sulfuric acid. Table 1. Sulfuric acid Production and Trade Data Sources Production and Trade Data Category Data Source Identifier Description Domestic Production 2020 TSCA Chemical Data Reporting CAS No.: 7664-93-9 Sulfuric Acid Imports and Exports U.S. International Trade Commission HS Code: 2807.00 Sulfuric Acid 2 &EPA ------- Sulfuric Acid Supply Chain - Full Profile Total U.S. domestic manufacturing of sulfuric acid was approximately 22,845 million kilograms (M kg) in 2019 (EPA, 2020). The majority of domestic commercial manufacture of sulfuric acid takes place at phosphate rock processing facilities located throughout the contiguous U.S. (The Mosaic Company, 2021; Potash, 2015). Many of these facilities are owned by a relatively small number of companies including the Mosaic Company (Mosaic) and PCS Phosphate fEPA, 2020). Mosaic reported production of approximately 10,000 M kg of sulfuric acid in 2019, and the majority was reported used on-site for production of phosphoric acid. Mosaic purchased the majority of sulfur used to produce the sulfuric acid from North American oil and natural gas refiners (The Mosaic Company, 2021). Domestic manufacturing of sulfuric acid is widely distributed throughout the U.S. The number of domestic manufacturing locations shown in Figure 2 represents operating facilities as of 2015. Supply of NSF/ANSI Standard 60 certified sulfuric acid for use in drinking water treatment is also widely distributed throughout the U.S. (NSF International, 2021). For a more current listing of manufacturing locations and supplier locations, visit the U.S. Environmental Protection Agency's (EPA's) Chemical Locator Tool (EPA, 2022a). 3 &EPA ------- Sulfuric Acid Supply Chain - Full Profile Domestic Consumption U.S. consumption of sulfuric acid in 2019 is estimated at 25,596 M kg. This includes production of 22,845 M kg, import of 2,970 M kg, minus export of 220 M kg (EPA, 2020; USITC, 2021), as shown in Figure 3. Domestic Consumption (2019): 25,596 M kg I ¦ Domestic Production (22,845 M kg) L ¦ Imports for Consumption (2,970 M kg) ¦ Export of Domestic Production (220 M kg) Figure 3. Domestic Production and Consumption of Sulfuric Acid in 2019 Trade & Tariffs Worldwide Trade Worldwide import and export data for sulfuric acid are reported through the World Bank's World Integrated Trade Solutions (WITS) software, as a category specific to sulfuric acid. In 2021, U.S. ranked 12th worldwide in total exports and first in total imports of sulfuric acid. In 2021, China ranked first worldwide in total exports (WITS, 2022), as shown in Table 2. Table 2. WITS Worldwide Export and Import of Sulfuric Acid in 2021 2021 Worldwide Trade Sulfuric Acid (HS Code 2807.00) Top 5 Worldwide Exporters Top 5 Worldwide Importers China 3,000 M kg United States 3,252 M kg Canada 1,904 M kg Chile 2,451 M kg Germany 1,136 M kg Morocco 2,109 M kg Peru 1,110 M kg India 1,874 M kg Mexico 970 M kg Philippines 1,522 M kg Domestic Imports and Exports Domestic import and export data are reported by USITC in categories specific to sulfuric acid. Figure 4 summarizes imports for consumption1 and domestic exports2 of sulfuric acid between 2015 and 2020. During this period, the overall quantity of imports and exports remained relatively steady, with imports for consumption exceeding domestic exports. Over this five-year period, Canada was the primary recipient of domestic exports and the primary source of imports (USITC, 2021). 1 Imports for consumption are a subset of general imports, representing the total amount cleared through customs and entering consumption channels, not anticipated to be reshipped to foreign points, but may include some reexports. 2 Domestic exports are a subset of total exports, representing export of domestic merchandise which are produced or manufactured in the U.S. and commodities of foreign origin which have been changed in the U.S. 4 &EPA ------- Sulfuric Acid Supply Chain - Full Profile Domestic Trade of Sulfuric Acid 4'000 HTS Code 2807.00 3,600 3,200 2,800 1 LI L I. L L tO 00 lO tO tO 1/5 CO tO tO to to tO t t t t t t t t: c t t oo oo oo oo oo oo Q.Q. Q.Q. Q.D. CL Q_ Q.Q. Q.Q. C X C X C X C X C X C X C(JJ C ll| C LJJ C LLI C Ljj C QJ Imports Exports Imports Exports Imports Exports Imports Exports Imports Exports Imports Exports 2015 2016 2017 2018 2019 2020 ¦ Imports from Canada ¦ Exports to Canada ¦ Imports from Mexico ¦ Exports to Mexico ¦ Imports from Other Countries Exports to Other Countries Figure 4. USITC Domestic Import and Export of Sulfuric Acid between 2015 and 2020 Tariffs There is no general duty for import of sulfuric acid, however there is an additional 25% duty on imports from China (USITC, 2022), as summarized in Table 3. Table 3. Domestic Tariff Schedule for Sulfuric Acid in 2020 HS Code General Duty Additional Duty - China (Section 301 Tariff List) Special Duty 2807.00 None 25% None Market History & Risk Evaluation History of Shortages The U.S. is one of the leading worldwide producers of sulfuric acid, and there were no identified significant supply chain disruptions between 2000 and 2022. However, there is a history of price volatility. The majority of elemental sulfur, the primary input in sulfuric acid manufacturing, is recovered as a byproduct of natural gas and petroleum processing. As described in the history of shortages for the sulfur supply chain profile (EPA, 2022b), the price and availability of sulfur is closely tied to demand for fuels and petroleum products (USGS, 2022). While the majority of recovered elemental sulfur is directed to manufacturing of sulfuric acid, demand for sulfuric acid, is tied to demand for fertilizer. Between 2020 and 2022, theses drivers have led to price fluctuations for sulfuric acid. Risk Evaluation The complete risk assessment methodology is described in Understanding Water Treatment Chemical Supply Chains and the Risk of Disruptions (EPA, 2022c). The risk rating is calculated as the product of the following three risk parameters: 5 SEPA ------- Sulfuric Acid Supply Chain - Full Profile Risk = Criticality x Likelihood x Vulnerability Criticality Measure of the importance of a chemical to the water sector Likelihood Measure of the probability that the chemical will experience a supply disruption in the future, which is estimated based on past occurrence of supply disruptions Vulnerability Measure of the market dynamics that make a chemical market more or less resilient to supply disruptions The individual parameter rating is based on evaluation of one or more attributes of the chemical or its supply chain. The ratings and drivers for these three risk parameters are shown below in Table 4. Table 4. Supply Chain Risk Evaluation for Sulfuric Acid Risk Parameter Ratings and Drivers 1 1 Criticality High 1 Likelihood Low 1 1 Vulnerability Low 1 Sulfuric acid is essential to the water sector and has widespread application for pH adjustment. It is a precursor in the production of numerous critical water treatment chemicals. The water sector did not experience sulfuric acid supply chain disruptions between 2000 and 2022. However, the water sector has experienced significant increases in price in the past. Concerns are primarily due to periodic reductions in production of Strong domestic manufacturing provides some resilience to supply disruptions. While the majority of domestic manufacturing is used to produce fertilizer, sulfuric acid is widely available. Risk Rating: Low AeO«-L°w M°deraf Rar>ge 'e/> A"\ k\ % -P oo f References Agency for Toxic Substances and Disease Registry (ATSDR), 1998. Toxicological profile for Sulfur, Sulfur Trloxlde, and Sulfuric Acid, retrieved from https://wwwn.cdc.gov/TSP/ToxProfiles/ToxProfiles.aspx?id=253&tid=46 CORECHEM, 2021. Sulfuric Acid Safety Data Sheet, retrieved from https://corecheminc.com/wp- content/uploads/2021/06/Sulfuric-Acid-93-98-Solution-CQRECHEM-lnc.-Safetv-Data-Sheet-2021.06.17- Revision-4.pdf EPA, 2016. 2016 TSCA Chemical Data Reporting, retrieved from https://www.epa.gov/chemical-data- reporting/access-cdr-data#2016 6 &EPA ------- Sulfuric Acid Supply Chain - Full Profile EPA, 2020. 2020 TSCA Chemical Data Reporting, retrieved from https://www.epa.gov/chemical-data- reporting/access-cdr-data#2020 EPA, 2022a. Chemical Suppliers and Manufacturers Locator Tool, retrieved from https://www.epa.gov/waterutilityresponse/chemical-suppliers-and-manufacturers-locator-tool EPA, 2022b. Sulfur Supply Chain - Full Profile, retrieved from https://www.epa.gov/waterutilityresponse/water-treatment-chemical-supplv-chain-profiles EPA, 2022c. Understanding Water Treatment Chemical Supply Chains and the Risk of Disruptions, retrieved from https://www.epa.gov/waterutilityresponse/risk-disruptions-supplv-water-treatment-chemicals McCoy, M., 2008. The Acid Touch: Rising prices for sulfuric acid have widespread industrial impact, Chemical & Engineering News, April 14, 2008, retrieved from https://cen.acs.org/articles/86/il5/Acid- Touch.html&cd=l&hl=en&ct=clnk&gl=us National Center for Biotechnology Information (NCBI), 2022. PubChem Compound Summary for CID 1118, Sulfuric Acid, retrieved from https://pubchem.ncbi.nlm.nih.gov/compound/1118 NSF International, 2021. Search for NSF Certified Drinking Water Treatment Chemicals, retrieved from https://info.nsf.org/Certified/PwsChemicals/ Potash Corporation of Saskatchewan, Inc. (Potash), 2015. Form 10-K2014, retrieved from https://www.sec.gov/Archives/edgar/data/855931/000119312515062Q91/d863198dl0k.htm The Mosaic Company, 2021. Form 10-K 2020, retrieved from https://investors.mosaicco.com/financials/sec- filings/default.aspx The Sulphur Institute, 2018. Evaluation of Loading and Unloading Operations for Sulphuric Acid and Spent Sulphuric Acid Rail Tank Cars, September 1, 2018, retrieved from https://www.sulphurinstitute.org/pub/?id=478a5ef2-c710-c5b3-ec9e-62947fac411e U.S. Geological Survey (USGS), 2022. 2018 Minerals Yearbook: Sulfur, retrieved from https://pubs.usgs.gov/mvb/voll/2018/mybl-2018-sulfur.pdf U.S. International Trade Commission (USITC), 2021. USITC DataWeb, retrieved from https://dataweb.usitc.gov/ U.S. International Trade Commission (USITC), 2022. Harmonized Tariff Schedule (HTS) Search, retrieved from https://hts.usitc.gov/current World Integrated Trade Solutions (WITS), 2022. Trade Statistics by Product (HS 6-digit), retrieved from https://wits.worldbank.org/trade/countrv-byhs6product.aspx?lang=en#void 7 &EPA ------- |