Other Basic Inorganic Chemical Manufacturing (U.S.) — NAICS 32518

A rollup primer for public-market and private investors. This is a NAICS (North American Industry Classification System) industry — the 5-digit level — and it contains exactly one child industry, 325180. For full detail, see the 325180 primer; this page explains why the two levels are the same and gives this level's own federal statistics.

1. Overview

NAICS 32518 is the industry that makes the workhorse chemicals almost nothing else can do without: chlorine and caustic soda, sulfuric and hydrochloric acid, carbon black, hydrogen peroxide, and a long tail of salts, oxides, and catalysts. These are "basic inorganic" chemicals — mostly mineral-derived molecules sold in bulk, by the ton, to other manufacturers rather than to consumers.[1]

For an investor, the appeal and the hazard are the same thing: these are commodity manufacturers that earn the spread between a volatile selling price and volatile energy and feedstock costs, running capital-heavy plants at high utilization. Returns are genuinely cyclical.

2. What's inside — and why this level equals its one child

At the 5-digit level, NAICS 32518 has a single 6-digit child, 325180 — same name, same scope. When a NAICS industry has only one national detail industry beneath it, the two are effectively identical: every firm, dollar, and plant counted at 32518 is also counted at 325180. So this page is a pass-through, and all the substance — products, company profiles, economics, and citations — lives in the 325180 primer.

For orientation, the scope covers chlor-alkali (chlorine and caustic soda), carbon black, inorganic acids and bases, and a long tail of salts, oxides, and intermediates. It excludes industrial gases (NAICS 325120), synthetic dyes and pigments including titanium dioxide (325130), mined soda ash (212391), and fertilizers (325311/325312) — all of which sit in other codes.[1]

3. How big it is (this level's figures)

Federal statistics for NAICS 32518 — identical to 325180 because it is the only child:

A roughly $42 billion shipments industry employing only ~41,000 people directly — the tell-tale signature of a capital-intensive, energy-intensive, low-headcount business where value comes from plant and process, not labor.

Undercount caveat — and it runs the other way. Federal coverage here is good: this is a business of large, permitted plants, not a cash economy or micro-operator field, so the count is not understated by hidden activity. If anything, the top line understates total U.S. inorganic-chemical output, because inorganic products made at plants coded to fertilizer, mining (soda ash), or plastics land in those buckets instead. The subtler point is the reverse of an undercount: the $42B aggregate hides how concentrated the individual product markets are (see §8).

Soda ash (outside 32518 but economically related): In 2025, the United States had four companies operating five Wyoming plants and one company operating one California plant, with combined nameplate capacity of 13.9 million metric tons annually. U.S. output was approximately 12.0 million metric tons, valued at about $1.8 billion. More than half was exported.[4]

4. The investable universe (where value concentrates)

Because 32518 = 325180, the investable map is the child's. There is no pure-play public company and no dedicated exchange-traded fund (ETF); exposure comes from diversified chemical makers where inorganics are a major segment. The cleanest listed names are Olin (NYSE: OLN) and Westlake (NYSE: WLK) in chlor-alkali, Orion (NYSE: OEC) and Cabot (NYSE: CBT) in carbon black, and Ecovyst (NYSE: ECVT) in sulfuric acid.[5][6][7] A large share of the industry is private or foreign-owned — Birla Carbon, Nouryon, Solvay, BASF — and as of January 2026 the largest domestic asset, OxyChem, sits inside Berkshire Hathaway (NYSE: BRK.B) after a $9.7 billion buyout; Occidental retained specified legacy environmental liabilities.[8][9] See the 325180 primer for the full company-by-company table.

5. How the money works

Owners make money by (a) sitting low on the cost curve (cheap power, scale, integration), (b) running high utilization when demand allows, and (c) capturing the spread between product prices and energy/feedstock costs through the cycle.[10] Two features are specific to inorganics: chlor-alkali's co-product trap — electrolysis makes chlorine and caustic soda in a fixed ~one-to-one ratio, so the two serve different end-markets and the blended price signal (the "ECU," or electrochemical unit) is what matters — and energy as the swing cost, where electricity is 40–60% of chlor-alkali production cost.[10]

Cyclicality in action. Olin's Chlor Alkali Products and Vinyls segment illustrates the operating leverage: 2025 sales of $3.684 billion and segment income of $181.1 million, versus $3.630 billion and $296.4 million in 2024.[5] Westlake's 2025 results showed the downside more starkly: it recorded a $727 million North American Chlorovinyls goodwill impairment and $393 million of closure costs.[11] Full mechanics are in the 325180 primer.

6. What drives demand

Demand is derived from downstream industries: construction and housing (chlorine → PVC pipe and siding), autos and tires (carbon black), water treatment (chlorine, caustic), alumina refining and pulp/paper (caustic soda), and fertilizer and metals processing (sulfuric acid).[12] A fast-growing pocket is ultra-pure chemicals for semiconductors and batteries.[13] In carbon black, most of the reinforcing-carbon market is replacement tires, historically less cyclical because it correlates with miles driven rather than new-vehicle production.[6]

7. Regulation

Regulation is a permanent operating cost, not an occasional event. The Clean Air Act's NESHAP (National Emission Standards for Hazardous Air Pollutants) govern chlor-alkali plants and the mercury-cell phase-out; carbon-black plants face their own NESHAP standards for benzene and other organics.[14][15] The EPA's 2024 asbestos rule immediately prohibited additional asbestos imports for chlor-alkali use and requires remaining asbestos-diaphragm plants to convert — EPA stated that eight U.S. chlor-alkali plants still used asbestos diaphragms when the rule was issued, with six required to transition within five years.[16] The Toxic Substances Control Act (TSCA), strengthened after 2016, drives chemical risk evaluations; and OSHA/EPA process-safety rules plus DOT hazmat-transport rules apply to handling chlorine and other toxics.[17] Trade policy — tariffs and anti-dumping cases on caustic soda and carbon black — also moves U.S. pricing.

8. Consolidation

The federal aggregate looks unconcentrated: the top four firms hold only 24.9% of receipts, the top eight 33.7%, the top twenty 51.1%, and the Herfindahl-Hirschman Index (HHI, a standard concentration score) is a low ~255.[2] But that is misleading, because 32518 lumps together many distinct product markets. Within any single product line, concentration is far higher — chlor-alkali is an oligopoly (Olin, Westlake, OxyChem/Berkshire), and carbon black is led by a small global set (Birla Carbon, Cabot, Orion).[7][18] The multi-decade trend is consolidation; the marquee recent deal is Berkshire Hathaway's January 2026 purchase of OxyChem for $9.7 billion.[8] WE Soda's $1.425 billion acquisition of Genesis Alkali's two Wyoming soda-ash operations in February 2025 is another significant consolidation.[19] Expect further rationalization: high energy costs and heavy environmental capital needs favor the largest, lowest-cost operators.

9. Risks

The same risk set as the child: cyclicality (earnings swing hard with construction, autos, and industrial production); energy and feedstock cost shocks; the chlor-alkali co-product imbalance; global oversupply and imports; environmental and safety liability (chlorine releases, legacy mercury, asbestos-diaphragm conversion requirements, tightening rules); capital intensity in long-lived, hard-to-shut assets that punish mistiming the cycle; carbon-black substitution (customers increasingly want recovered or lower-carbon material, while precipitated silica competes in some tire applications); and customer concentration (five major tire customers represent a material portion of Cabot's Reinforcement Materials sales).[5][6][10]

10. How to invest, and the outlook

Because this level is its one child, the how-to-invest path is 325180's. Public route: direct equities — Olin and Westlake for chlor-alkali, Orion and Cabot for carbon black, Ecovyst for sulfuric acid — plus diluted exposure through broad materials-sector funds; there is no 32518 ETF. Private route: most of the industry is private or foreign-owned, so private-equity and direct-operator paths dominate, with Berkshire now the largest single holder via OxyChem.[8]

Outlook (forward-looking judgment, not established fact). The chlor-alkali cycle came through a soft patch on weak PVC and caustic pricing in 2024–2025, with tentative volume and price recovery the near-term swing factor.[20] Two structural threads favor patient owners: the U.S. energy-cost advantage (cheap natural-gas power versus Europe) and growth in ultra-pure inorganics for semiconductors and batteries.[13] Chlor-alkali produces hydrogen as a coproduct; Olin recorded a $34.5 million benefit principally related to the federal 45V hydrogen credit in 2025, signaling potential upside from decarbonization policy.[5] Berkshire's willingness to pay ~$9.7 billion for OxyChem is a strong vote of confidence in the long-run cash economics of these assets.[8] The counterweights — energy-price and oversupply risk, tightening environmental rules, and unavoidable cyclicality — are equally real.

For the full analysis, read the 325180 primer.

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Sources

1. NAICS Association. "NAICS Code 325180 — Other Basic Inorganic Chemical Manufacturing" (definition, scope, and exclusions). 2022. https://www.naics.com/naics-code-description/?code=325180
2. U.S. Census Bureau. Economic Census 2022 — Concentration and receipts, NAICS 32518/325180 (receipts $41.86B, 413 firms, CR4 24.9%, CR8 33.7%, CR20 51.1%, CR50 73.9%, HHI 255.2). 2022. https://www.census.gov/programs-surveys/economic-census.html
3. U.S. Census Bureau. County Business Patterns 2023 — NAICS 325180 (705 establishments, ~41,447 employees, $4.4B annual payroll). 2023. https://www.census.gov/programs-surveys/cbp.html
4. U.S. Geological Survey. Mineral Commodity Summaries 2026 — Soda Ash (capacity, output, value, end-use shares, exports). 2026. https://pubs.usgs.gov/periodicals/mcs2026/mcs2026.pdf
5. Olin Corporation. Form 10-K, fiscal year 2025 (segment results, salt integration, hydrogen credit). 2026. https://www.sec.gov/Archives/edgar/data/74303/000007430326000027/oln-20251231.htm
6. Cabot Corporation. Annual Report 2025 (carbon-black feedstocks, contract pass-throughs, Reinforcement Materials segment, customer concentration, secular trends). 2025. https://www.cabotcorp.com/-/media/files/reports/company/cabot-corporation-annual-report-2025.pdf
7. MarketsandMarkets. "Chlor-Alkali Companies — Top Industry Manufacturers" (Olin ~18% and Westlake ~12% of global capacity). 2024. https://www.marketsandmarkets.com/ResearchInsight/chlor-alkali-market.asp
8. Chemical & Engineering News (C&EN), American Chemical Society. "Berkshire Hathaway to buy OxyChem for $9.7 billion." 2025. https://cen.acs.org/business/petrochemicals/Berkshire-Hathaway-buy-OxyChem-97/103/web/2025/10
9. Occidental Petroleum. Form 10-K, fiscal year 2025 (OxyChem sale, retained environmental liabilities). 2026. https://www.sec.gov/Archives/edgar/data/797468/000162828026009059/oxy-20251231.htm
10. Thunder Said Energy. "Chlor-Alkali Process: The Economics" (ECU definition; electricity 40–60% of cost; co-product ratio and cyclicality). 2024. https://thundersaidenergy.com/downloads/chlor-alkali-process-the-economics/
11. Westlake Corporation. Form 10-K, fiscal year 2025 (goodwill impairment, closure costs). 2026. https://ebs.publicnow.com/view/3C05E2A8A109C07A1B6DA2201C672DCD85E8DEB8
12. IndexBox. "Chlor-Alkali Chemicals Market Forecast … on PVC Demand and Water Treatment Expansion" (demand drivers: PVC/vinyls, alumina, pulp & paper, water treatment). 2024. https://www.indexbox.io/blog/chlor-alkali-chemicals-market-forecast-points-higher-toward-2035-on-pvc-demand-and-water-treatment-expansion/
13. Market.us. "Global Chlor-Alkali Market" (producer investment in ultra-pure caustic for semiconductors and batteries). 2024. https://market.us/report/global-chlor-alkali-market/
14. U.S. Environmental Protection Agency. "Mercury Cell Chlor-Alkali Plants: National Emission Standards for Hazardous Air Pollutants (NESHAP)." 2022. https://www.epa.gov/stationary-sources-air-pollution/mercury-cell-chloralkali-plants-national-emissions-standards
15. U.S. Environmental Protection Agency. "Carbon Black Production Area Sources: National Emission Standards for Hazardous Air Pollutants (NESHAP)." https://www.epa.gov/stationary-sources-air-pollution/carbon-black-production-area-sources-national-emission-standards
16. U.S. Environmental Protection Agency. "Biden-Harris Administration Finalizes Ban on Ongoing Uses of Asbestos to Protect People from Cancer" (2024 asbestos rule, chlor-alkali conversion requirements). 2024. https://www.epa.gov/newsreleases/biden-harris-administration-finalizes-ban-ongoing-uses-asbestos-protect-people-cancer
17. U.S. EPA / Federal Register. "Procedures for Chemical Risk Evaluation Under the Toxic Substances Control Act (TSCA)." 2025. https://www.federalregister.gov/documents/2025/09/23/2025-18431/procedures-for-chemical-risk-evaluation-under-the-toxic-substances-control-act-tsca
18. Fact.MR. "Tire Carbon Black Market" (key players Birla Carbon, Cabot, Orion, Continental Carbon). 2025. https://www.factmr.com/report/tire-carbon-black-market
19. Genesis Energy L.P. SEC filing (WE Soda acquisition of Genesis Alkali for $1.425B enterprise value). 2025. https://www.sec.gov/Archives/edgar/data/1022321/000119312525047270/d870215dex991.htm
20. Olin Corporation. "Olin Announces Fourth Quarter 2024 Results" (full-year 2024 sales $6.54B; chlor-alkali segment; caustic pricing). 2025. https://www.prnewswire.com/news-releases/olin-announces-fourth-quarter-2024-results-302364834.html