Topic clusters
Each cluster aggregates the Sourzi reference moat around one substance: the glossary terms a procurement manager will meet, the CAS profile, the five regulatory regime pages, the cornerstone hub where one exists, the Chinese industrial parks that produce it, and the freight-form references that decide the booking.
Cross-linked at the structured-data layer with Schema.org CollectionPage and isPartOf references so search and AI engines can resolve the topical cluster a page belongs to.
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Sodium hydroxide (caustic soda)
氢氧化钠 / 烧碱
Sodium hydroxide is the workhorse of the chlor-alkali chain and the second-largest tonnage chemical Sourzi sources out of China. Solid 99% caustic ships in 25 kg bags or 1 t big bags, 50% liquid ships in IBCs or PE-lined T11 ISO tanks, and the container weight-out beats the cube-out almost every time. The Chinese supply base is concentrated in Shandong, Jiangsu, and Inner Mongolia, with Tianjin Nangang and the Bohua complex on the north-coast lane and the membrane-cell chlor-alkali clusters along the Yangtze. US imports carry Section 301 at 25 percent, which moves landed cost more than the FOB China price for most buyers. Quality risk concentrates on production route: membrane-cell caustic is the modern standard with low salt and low metals, mercury-cell caustic from legacy plants is deprecated and not accepted by US food or pharma buyers. This cluster aggregates the Sourzi reference moat around CAS 1310-73-2, with the regulatory profile across REACH, TSCA, IECSC, AICIS, and K-REACH, the substance-level CAS page, and the cornerstone hub with grade selection and freight maths.
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Sulfuric acid
硫酸
Sulfuric acid is the highest-tonnage industrial chemical on the planet and one of the most concentrated dangerous-goods bookings a sourcing manager will run. The 98 percent grade ships UN 1830, IMDG Class 8, Packing Group II in rubber-lined or 316L stainless ISO tanks; the dilute battery-acid grade ships UN 2796 in HDPE drums and IBCs. Density at 1.84 means weight-out hits long before cube-out, and the 80 percent surge floor in IMDG Code Chapter 4.2 catches first-time T11 bookings that look fine on paper. Chinese capacity sits across Shandong, Jiangsu, and Yunnan, with the Wengfu phosphate-complex base on the south-western coal-chemical lane. US imports run a small Section 301 exposure that varies by tariff sub-line. This cluster aggregates CAS 7664-93-9 across the regulatory matrix, the substance-level CAS reference, and the sulfuric-acid hub for grade selection and tank-type matching.
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Urea
尿素
Urea is the largest single-nitrogen fertiliser by tonnage and an industrial reductant in DEF / AdBlue applications for diesel exhaust. The granular grade trades at a premium to prilled because of compatibility with bulk-blending plants for compound fertiliser, and the technical grade for SCR catalysts carries a tighter biuret and metals spec. Chinese supply concentrates in Shandong, Henan, and Inner Mongolia, with coal-anthracite gasification feedstock in the inland clusters and natural-gas reforming on the coastal Yangtze. The export rebate position moves with the season and the China State Taxation Administration bulletin in effect at export. US imports do not carry a Section 301 line on prilled or granular at the time of writing, though buyers should verify against the current USTR list before quoting landed cost. This cluster aggregates CAS 57-13-6 across the regulatory matrix and the cornerstone hub with grade selection, packaging economics, and the failure modes that catch first-time buyers.
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Methanol
甲醇
Methanol is the highest-volume solvent and feedstock chemical in the Sourzi sourcing book, with applications running across formaldehyde resins, MTBE, biodiesel, and direct fuel use. Class 3 Packing Group II flammable, UN 1230 if the cargo carries water, UN 1230 with a sub-risk of Class 6.1 toxicity if the route requires the toxic-by-inhalation marker. Chinese capacity is dominated by coal-to-methanol in Inner Mongolia and Shanxi, with natural-gas reforming legacy units on the south-eastern coast. Ships in T11 ISO tanks for tonnage, drums for sample volumes; bottom-outlet stainless is the standard. US imports do not carry Section 301 on bulk methanol at the time of writing, though the rate moves with USTR review cycles. This cluster aggregates CAS 67-56-1 across the regulatory matrix, the substance-level CAS page, and the methanol hub with grade selection and freight maths.
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Citric acid
柠檬酸
Citric acid is the largest single fermentation chemical out of China by export tonnage and the workhorse acidulant for food, beverage, and cleaning applications. Anhydrous and monohydrate grades trade at different price points and require different packaging dryness controls. The supply base is dominated by RZBC, TTCA, and Cofco Biochemical, with corn-starch feedstock in Shandong and Anhui driving cost. US imports carry an anti-dumping duty order that has been in place since the 2009 USITC investigation and continues to be reviewed; verify against access.trade.gov before invoicing. Section 301 sits on top of the AD margin where it applies, so the duty stack on this code can run substantially above the FOB China price for first-time importers. This cluster aggregates CAS 77-92-9 across the regulatory matrix, the CAS page, and the citric-acid hub with grade selection and the buying notes that decide whether the cargo lands food-grade or technical-grade.
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Titanium dioxide
二氧化钛 / 钛白粉
Titanium dioxide is the most-traded white pigment globally and the single largest pigment line for paint, plastic, paper, and ink applications. Chinese capacity is dominated by Lomon Billions, Henan Billions, and Cnano, with sulphate-process plants in Sichuan and Anhui and chloride-process capacity expanding in Yunnan. The chloride-process grade commands a premium over sulphate for high-durability paint and engineering plastic applications. The 2021 IARC Group 2B classification on inhalable TiO2 has driven labelling changes globally, with REACH harmonised classification under CLP, OSHA HCS in the US, and AICIS notification in Australia. US imports do not carry Section 301 at the bulk-pigment level. This cluster aggregates CAS 13463-67-7 across the regulatory matrix, the substance-level CAS page, and the titanium-dioxide hub with grade selection, packaging economics, and the failure modes that catch first-time buyers.
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Monoethylene glycol (MEG)
乙二醇 / 单乙二醇
Monoethylene glycol is the second feedstock for PET resin (with PTA), and one of the highest-tonnage petrochemical movers on the China-export book. MEG ships UN 1593 if classified, IMDG Class 9 in some jurisdictions, in T11 stainless ISO tanks for bulk and drums for sample shipments. Chinese capacity is split between coal-to-MEG plants in Inner Mongolia and ethylene-cracker MEG on the south-eastern coast (Huizhou, Ningbo). Coal-MEG carries trace acids and aldehydes that some downstream polyester producers specify against; the petrochemical route is the gold-standard grade for high-tenacity bottle-grade PET. This cluster aggregates CAS 107-21-1 across the regulatory matrix, the CAS page, and the MEG hub.
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Polyvinyl chloride (PVC)
聚氯乙烯
Polyvinyl chloride is the third-largest polymer by volume globally and the single largest commodity polymer line from China, with capacity dominated by calcium-carbide acetylene route in Xinjiang and Inner Mongolia and ethylene-route capacity in coastal clusters. PVC suspension (S-PVC) is the bulk grade for pipe, profile, and film; PVC emulsion (E-PVC) and microsuspension grades serve coating and specialty applications. The 2024 US Section 301 review added select PVC and downstream codes to the list at 25 percent. Chinese supply sits in Ningbo Petrochemical, Tianjin Nangang, and the Inner Mongolia carbide complexes. This cluster aggregates CAS 9002-86-2 across the regulatory matrix and the PVC hub. The CAS 9002-86-2 is a polymer registration; the substance-level CAS page is not the same surface and is therefore not included.
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Ammonium sulfate
硫酸铵
Ammonium sulfate is a 21-0-0 plus 24 percent sulphur nitrogen-sulphur fertiliser and a key blending component in compound fertiliser plants. Two production routes split Chinese supply: caprolactam by-product (around 70 percent of supply) and synthetic from ammonia plus sulfuric acid. The caprolactam by-product carries trace caprolactam impurities that some downstream blenders specify against. Granular grade trades at a premium to crystalline because of bulk-blending compatibility. Chinese supply concentrates in Henan, Shandong, Jiangsu, and Hebei. US imports do not carry Section 301 on the fertiliser-grade material at the time of writing. This cluster aggregates CAS 7783-20-2 across the regulatory matrix, the CAS page, and the ammonium-sulfate hub.
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Purified terephthalic acid (PTA)
精对苯二甲酸
Purified terephthalic acid is the first feedstock for PET resin and polyester fibre. Chinese PTA capacity is the largest in the world, concentrated in Hengli (Dalian), Yisheng (Ningbo), and Sinopec (Yangzi). The China-to-PET-resin chain is vertically integrated for most large producers, with PX-PTA-PET running on the same coastal complex. PTA does not carry IMDG dangerous-goods classification for routine sea transport; ships in bulk 1 t big bags or container-loaded paper bags. US imports carry no Section 301 on bulk PTA at the time of writing. This cluster aggregates CAS 100-21-0 across the regulatory matrix and the PTA hub. The PTA grade spec for bottle-resin versus fibre-resin is the loadbearing buying decision and the cornerstone hub walks through it.
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Phenol
苯酚
Phenol is the precursor for bisphenol-A, phenolic resin, and caprolactam, with Chinese capacity dominated by Sinopec and large private petrochemical complexes. UN 1671 (solid) or UN 2821 (solution), IMDG Class 6.1 Packing Group II for the toxicity profile; ships in heated ISO tanks for molten bulk or paper bags for solid. Phenol crystallises at 41 degrees Celsius so cold-weather shipments demand heated tanks or pre-melted IBCs. Chinese capacity is integrated with cumene plants in Ningbo, Huizhou, and the Yangtze coastal complexes. US imports do not carry Section 301 on bulk phenol at the time of writing. This cluster aggregates CAS 108-95-2 across the regulatory matrix.
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Caprolactam
己内酰胺
Caprolactam is the monomer for Nylon-6 fibre and resin, and the precursor to ammonium-sulfate by-product through the Beckmann rearrangement. Chinese capacity is the largest globally, dominated by Sinopec (Baling, Shijiazhuang), Hengyi, and Sanning. The downstream Nylon-6 chain runs at scale in Jiangsu, Henan, and Shandong; the ammonium-sulfate by-product feeds the compound-fertiliser blending sector. UN 2811, IMDG Class 6.1 PG III in molten bulk; ships in heated ISO tanks for bulk and 25 kg PE-lined paper bags for flake. US imports do not carry Section 301 on bulk caprolactam at the time of writing. This cluster aggregates CAS 105-60-2 across the regulatory matrix.
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Acrylonitrile
丙烯腈
Acrylonitrile is the monomer for ABS resin, acrylic fibre, and styrene-acrylonitrile copolymers. Chinese capacity is dominated by Sinopec, with large complexes in Shanghai, Anqing, and the Bohai-rim petrochemical zones. UN 1093, IMDG Class 3 Packing Group I, sub-risk Class 6.1 for inhalation toxicity; the highest-tier dangerous-goods classification for a routine commodity petrochemical shipment. Ships in stainless or rubber-lined T11 ISO tanks with the inhibitor MEHQ (methoxyhydroquinone) at the spec rate. IARC Monograph 71 classifies acrylonitrile as Group 2B (possibly carcinogenic), and the 2021 IARC re-evaluation in Volume 128 reaffirmed the classification. US imports do not carry Section 301 on bulk acrylonitrile at the time of writing. This cluster aggregates CAS 107-13-1 across the regulatory matrix.
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Benzene
苯
Benzene is the largest aromatic feedstock by volume and the precursor to styrene, cumene, cyclohexane, and aniline. Chinese capacity sits at integrated reformer-aromatic complexes in Ningbo, Huizhou, Dalian, and Tianjin. UN 1114, IMDG Class 3 Packing Group II flammable, with the additional carcinogen warning from IARC Group 1 classification. Ships in stainless T11 ISO tanks for tonnage and drums for sample volume. The 1 ppm OSHA PEL on benzene exposure drives strict receiver-side handling requirements. Chinese export VAT rebate moves with the State Taxation Administration schedule; US imports carry a small Section 301 exposure on select downstream codes. This cluster aggregates CAS 71-43-2 across the regulatory matrix and the CAS page.
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Styrene monomer
苯乙烯
Styrene monomer is the feedstock for polystyrene, ABS, SAN, and SBR rubber. Chinese capacity has more than doubled since 2020, with new world-scale complexes in Zhejiang and Liaoning bringing the country to net export. UN 2055, IMDG Class 3 Packing Group III flammable; ships in stainless T11 ISO tanks with the TBC (tert-butylcatechol) inhibitor at the spec rate (typically 10 to 50 ppm). Polymerisation risk in the tank is the dominant cargo-loss mode, and the inhibitor decay clock is real for any shipment older than 60 days from production. IARC Monograph 121 reclassified styrene as Group 2A (probably carcinogenic) in 2018. US imports do not carry Section 301 on bulk styrene at the time of writing. This cluster aggregates CAS 100-42-5 across the regulatory matrix and the CAS page.
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Acetic acid
醋酸 / 乙酸
Acetic acid is the feedstock for vinyl-acetate monomer, PTA via the Eastman route, and acetic anhydride. Chinese capacity is dominated by methanol-carbonylation plants in Inner Mongolia, Shanxi, and the Yangtze petrochemical complexes. Glacial 99.5 percent grade ships UN 2789, IMDG Class 8 Packing Group II in stainless T11 ISO tanks or 200 kg HDPE drums. The lower-strength solutions (10 to 25 percent) ship without dangerous-goods classification under UN 2790 thresholds. US imports do not carry Section 301 on bulk acetic acid at the time of writing. This cluster aggregates CAS 64-19-7 across the regulatory matrix and the CAS page.
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Hydrochloric acid
盐酸
Hydrochloric acid is the chlor-alkali by-product acid and a workhorse for pH adjustment, steel pickling, ore leaching, and water treatment. Concentrated 30 to 36 percent grade ships UN 1789, IMDG Class 8 Packing Group II in HDPE drums, IBCs, or rubber-lined ISO tanks. The fumes generate hydrogen-chloride gas, and the receiver-side ventilation requirement is non-trivial. Chinese supply concentrates in Shandong (chlor-alkali by-product) and Jiangsu, with the bulk of export tonnage moving on north-coast lanes. US imports do not carry Section 301 on bulk HCl at the time of writing. This cluster aggregates CAS 7647-01-0 across the regulatory matrix and the CAS page.
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Ammonium hydroxide (aqueous ammonia)
氢氧化铵 / 氨水
Ammonium hydroxide (aqueous ammonia) is the water-solution form of ammonia gas, used for cleaning, water treatment, and chemical-synthesis applications. UN 2672 for solutions 10 to 35 percent, IMDG Class 8 Packing Group III; UN 2073 for 35 to 50 percent solutions, IMDG Class 2.2 plus 8. Ships in stainless or HDPE-lined T11 ISO tanks, IBCs, or HDPE drums. Chinese supply concentrates in the Yangtze and Bohai coastal chemical clusters where ammonia is co-produced with urea and nitrogen-fertiliser chains. US imports do not carry Section 301 on aqueous ammonia at the time of writing. This cluster aggregates CAS 1336-21-6 across the regulatory matrix and the CAS page.
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Formaldehyde
甲醛
Formaldehyde is the precursor for urea-formaldehyde resin, melamine-formaldehyde resin, phenol-formaldehyde resin, and a wide range of fine-chemistry intermediates. Ships as 37 to 50 percent aqueous solution (formalin) under UN 2209, IMDG Class 9 (or Class 3 if the methanol stabiliser content is high enough). Chinese capacity is integrated with methanol plants in Inner Mongolia, Shandong, and the Yangtze chemical complexes. IARC Group 1 carcinogen classification drives strict receiver-side handling and exposure-monitoring requirements at any plant taking bulk formalin. US imports do not carry Section 301 on bulk formalin at the time of writing. This cluster aggregates CAS 50-00-0 across the regulatory matrix and the CAS page.
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Hydrogen peroxide
过氧化氢
Hydrogen peroxide is a bleaching agent, water-treatment oxidiser, and chemical-synthesis intermediate. Strength varies by application: 35 percent for pulp-and-paper bleaching, 50 percent for water treatment and electronics, 70 percent for high-performance synthesis. UN 2014, IMDG Class 5.1 Packing Group II for 8 to 60 percent solutions; UN 2015, IMDG Class 5.1 Packing Group I for solutions above 60 percent. Ships in HDPE drums, IBCs, or dedicated stainless or aluminium ISO tanks. Chinese capacity is dominated by Shandong-based and Jiangsu-based producers using the anthraquinone-autoxidation process. US imports do not carry Section 301 on bulk H2O2 at the time of writing. This cluster aggregates CAS 7722-84-1 across the regulatory matrix and the CAS page.
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Acetone
丙酮
Acetone is a high-volume ketone solvent and a feedstock for methyl methacrylate, bisphenol A, and aldol-condensation downstream products. Chinese capacity is dominated by phenol-acetone co-product plants in Ningbo, Yangtze River, and the Bohai-rim petrochemical complexes; the cumene oxidation route gives the same molar yield of phenol and acetone, so the chains move together. UN 1090, IMDG Class 3 Packing Group II flammable; ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. The flashpoint at minus 20 degrees Celsius drives strict no-spark loading discipline at the terminal. US imports do not carry Section 301 on bulk acetone at the time of writing, though buyers should verify against the current USTR list before quoting landed cost. This cluster aggregates CAS 67-64-1 across the regulatory matrix and the substance-level CAS reference.
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Ethanol (industrial ethyl alcohol)
乙醇 / 工业酒精
Industrial ethanol covers fuel-grade, denatured, and synthetic grades. Chinese supply splits between corn-fermentation in Heilongjiang and Jilin and synthetic ethylene-hydration capacity on the south-eastern coast. The food-grade and pharma-grade routes carry separate GMP certifications and price tiers. UN 1170, IMDG Class 3 Packing Group II for solutions above 24 percent; ships in stainless T11 ISO tanks, IBCs, or 200 kg HDPE drums. US imports do not carry Section 301 on bulk industrial ethanol at the time of writing, though the broader fuel-ethanol policy environment shifts with EPA Renewable Fuel Standard reviews. This cluster aggregates CAS 64-17-5 across the regulatory matrix and the substance-level CAS reference. The denaturation specification on the COA decides the importer-side duty classification at customs; verify against the destination tariff schedule before quoting.
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Isopropyl alcohol (IPA)
异丙醇
Isopropyl alcohol is a high-purity solvent for electronics cleaning, pharmaceutical synthesis, and cosmetics formulation. Electronic-grade IPA carries a sub-ppb metals spec and ships in dedicated PE-lined drums or polypropylene IBCs; industrial grade ships in stainless T11 ISO tanks for tonnage. UN 1219, IMDG Class 3 Packing Group II flammable. Chinese capacity sits in Yangtze River and Bohai-rim petrochemical complexes, with the propylene-hydration route dominant. The Korean and Japanese semiconductor lanes pay a 30 to 60 percent premium over industrial grade because of the metals spec. US imports do not carry Section 301 on bulk IPA at the time of writing. This cluster aggregates CAS 67-63-0 across the regulatory matrix and the substance-level CAS reference.
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Methyl ethyl ketone (MEK)
甲乙酮
Methyl ethyl ketone is a workhorse ketone solvent for ink, adhesive, coating, and dewaxing applications. Chinese capacity is dominated by the n-butene-hydration route in Bohai-rim and Yangtze petrochemical complexes. UN 1193, IMDG Class 3 Packing Group II flammable; ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. US Section 301 status varies by tariff sub-line; verify against the current USTR list before quoting landed cost. China-Australia and China-Southeast-Asia lanes are stable; the US lane sees periodic anti-dumping reviews on Asian MEK that buyers should verify against access.trade.gov before invoicing. This cluster aggregates CAS 78-93-3 across the regulatory matrix and the substance-level CAS reference.
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Acetonitrile
乙腈
Acetonitrile is the dominant solvent for HPLC analytical work, lithium-battery electrolyte production, and pharma synthesis. Chinese capacity is dominated by acrylonitrile by-product plants in Shanghai and the Bohai-rim petrochemical complexes; the supply tightens whenever the acrylonitrile main chain runs at reduced rate. UN 1648, IMDG Class 3 Packing Group II flammable; the inhalation toxicity sub-risk drives strict receiver-side handling. Ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. The HPLC-grade specification is significantly tighter than industrial-grade on water, UV cutoff, and trace metals. US imports do not carry Section 301 on bulk acetonitrile at the time of writing. This cluster aggregates CAS 75-05-8 across the regulatory matrix and the substance-level CAS reference.
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Dichloromethane (DCM, methylene chloride)
二氯甲烷
Dichloromethane is a chlorinated solvent for paint stripping, pharma extraction, and decaffeination of coffee and tea. Chinese capacity sits in Shandong and Jiangsu chlor-alkali derivative chains. UN 1593, IMDG Class 6.1 Packing Group III; ships in stainless or PE-lined T11 ISO tanks for bulk and steel or HDPE drums for sample volume. The US EPA TSCA Section 6 rule on DCM in consumer paint-stripper applications has been in force since 2019, and the broader TSCA risk evaluation has narrowed approved industrial uses; verify against epa.gov/assessing-and-managing-chemicals-under-tsca before invoicing US shipments. This cluster aggregates CAS 75-09-2 across the regulatory matrix and the substance-level CAS reference.
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n-Hexane
正己烷
n-Hexane is a non-polar solvent for vegetable-oil extraction, rubber-cement formulation, and pharma synthesis. Chinese capacity is dominated by refinery-derived light-naphtha hexane cuts. UN 1208, IMDG Class 3 Packing Group II flammable; the neurotoxicity profile (peripheral neuropathy on chronic inhalation exposure) drives strict OSHA PEL and receiver-side handling requirements. Ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. Food-grade hexane for edible-oil extraction carries a tighter aromatics spec (under 50 ppm benzene typical) than industrial-grade. US imports do not carry Section 301 on bulk hexane at the time of writing. This cluster aggregates CAS 110-54-3 across the regulatory matrix and the substance-level CAS reference.
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Toluene (methylbenzene)
甲苯
Toluene is a high-volume aromatic solvent and feedstock for benzene-toluene-xylene downstream chains, TDI production, and aviation-fuel blending. Chinese capacity sits at integrated reformer-aromatic complexes in Ningbo, Dalian, Huizhou, and Tianjin. UN 1294, IMDG Class 3 Packing Group II flammable. Ships in stainless T11 ISO tanks for bulk and drums for sample volume. The IARC Group 3 classification (not classifiable as carcinogenic) is less restrictive than benzene, but the inhalation neurotoxicity profile still drives meaningful receiver-side handling requirements. US imports do not carry Section 301 on bulk toluene at the time of writing, though downstream TDI codes carry separate exposures. This cluster aggregates CAS 108-88-3 across the regulatory matrix and the substance-level CAS reference.
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Xylene (mixed isomers)
混合二甲苯
Mixed xylenes feed para-xylene separation for the PTA-PET chain and ortho-xylene production for phthalic anhydride. Chinese para-xylene capacity has more than doubled since 2018 on the Hengli, Yisheng, and Zhejiang Petrochemical mega-complexes, with the PX-PTA-PET integration running at world-scale on a single coastal site. UN 1307, IMDG Class 3 Packing Group III flammable. Ships in stainless T11 ISO tanks for bulk and drums for sample volume. US imports do not carry Section 301 on bulk mixed xylenes at the time of writing. This cluster aggregates CAS 1330-20-7 across the regulatory matrix and the substance-level CAS reference.
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Ethyl acetate
乙酸乙酯
Ethyl acetate is the highest-volume ester solvent for ink, adhesive, coating, and pharma applications. Chinese capacity is dominated by ethanol-acetic-acid esterification plants in Shandong, Jiangsu, and the Yangtze petrochemical complexes. UN 1173, IMDG Class 3 Packing Group II flammable; ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. The food-contact and pharma-grade specifications carry separate certifications and a 5 to 15 percent price premium over technical-grade. US imports carry an anti-dumping order on ethyl acetate from China in some sub-lines that varies by review cycle; verify against access.trade.gov before invoicing. This cluster aggregates CAS 141-78-6 across the regulatory matrix.
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n-Butyl acetate
乙酸正丁酯
n-Butyl acetate is a medium-evaporation-rate ester solvent for coating, ink, and adhesive formulations, with higher solvency power and slower flash-off than ethyl acetate. Chinese capacity is dominated by n-butanol-acetic-acid esterification plants in the Yangtze and Bohai-rim chemical clusters. UN 1123, IMDG Class 3 Packing Group III flammable; ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. The food-grade and pharma-grade specifications carry separate certifications. US imports do not carry Section 301 on bulk n-butyl acetate at the time of writing. This cluster aggregates CAS 123-86-4 across the regulatory matrix.
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Propylene oxide (PO)
环氧丙烷
Propylene oxide is the precursor for polyether polyols (PU foam and elastomers) and propylene glycol. Chinese capacity is dominated by the HPPO (hydrogen-peroxide-to-PO) route and the chlorohydrin legacy route, with mega-complexes in Bohai-rim and Yangtze River chemical zones. UN 1280, IMDG Class 3 Packing Group I (the highest-risk flammable packing group for routine petrochemical shipments); the low flashpoint at minus 37 degrees Celsius and the wide explosive range drive strict bonding and grounding requirements at the terminal. Ships in stainless T11 ISO tanks with nitrogen blanket. IARC Group 2B classification (possibly carcinogenic) drives stricter receiver-side handling. US imports do not carry Section 301 on bulk PO at the time of writing. This cluster aggregates CAS 75-56-9 across the regulatory matrix.
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Ethylene oxide (EO)
环氧乙烷
Ethylene oxide is the precursor for monoethylene glycol, ethanolamines, ethoxylated surfactants, and medical-device sterilisation. Chinese capacity is integrated with cracker-MEG complexes in Shanghai, Ningbo, Huizhou, and Dalian; the merchant-EO market is thin because most production is captive to downstream MEG. UN 1040, IMDG Class 2.3 (toxic gas) plus 2.1 (flammable gas) sub-risk; ships in dedicated stainless T75 cryogenic ISO tanks with strict cooling and inert-gas control. IARC Group 1 carcinogen classification drives the highest-tier receiver-side handling at every plant taking bulk EO. US imports do not carry Section 301 on bulk EO at the time of writing, though the regulated-substance scrutiny under TSCA Section 5 is constant. This cluster aggregates CAS 75-21-8 across the regulatory matrix.
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Ethylene dichloride (EDC, 1,2-dichloroethane)
二氯乙烷
Ethylene dichloride is the intermediate between ethylene and vinyl chloride monomer in the integrated PVC chain. Chinese capacity is integrated at every major chlor-alkali petrochemical complex; merchant EDC trade is dominated by short-haul movements between PVC chains within China and to neighbouring Asian PVC plants. UN 1184, IMDG Class 3 Packing Group II flammable; the IARC Group 2B classification (possibly carcinogenic) drives strict receiver-side handling. Ships in stainless T11 ISO tanks for bulk. US imports do not carry Section 301 on bulk EDC at the time of writing. This cluster aggregates CAS 107-06-2 across the regulatory matrix.
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Vinyl chloride monomer (VCM)
氯乙烯单体
Vinyl chloride monomer is the polymerisation feedstock for PVC. Chinese capacity is integrated at every major PVC complex; the carbide-acetylene route dominates in Inner Mongolia and Xinjiang, the ethylene-EDC-VCM route dominates on the coastal complexes. UN 1086, IMDG Class 2.1 (flammable gas) with sub-risk 2A carcinogen; ships in dedicated stainless T50 pressure ISO tanks under refrigeration. IARC Group 1 carcinogen classification drives the highest-tier receiver-side handling and exposure-monitoring at every plant taking bulk VCM. US imports do not carry Section 301 on bulk VCM at the time of writing; the China-to-US lane is thin because integrated US producers cover most demand. This cluster aggregates CAS 75-01-4 across the regulatory matrix.
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1,3-Butadiene
丁二烯
1,3-Butadiene is the monomer for synthetic rubber (SBR, BR, NBR) and ABS resin. Chinese capacity is dominated by ethylene-cracker by-product extraction in Bohai-rim and Yangtze petrochemical complexes; on-purpose butadiene from butane dehydrogenation is the marginal supplier. UN 1010, IMDG Class 2.1 (flammable gas) with sub-risk 2A carcinogen; ships in dedicated stainless T50 pressure ISO tanks. The inhibitor (TBC or related) is loadbearing; under-inhibited butadiene polymerises in the tank into popcorn polymer that cannot be discharged. IARC Group 1 carcinogen classification drives strict receiver-side handling. US imports do not carry Section 301 on bulk butadiene at the time of writing. This cluster aggregates CAS 106-99-0 across the regulatory matrix.
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Cumene (isopropylbenzene)
异丙苯
Cumene is the intermediate to phenol and acetone via the Hock process; over 95 percent of global cumene output feeds phenol production. Chinese capacity is integrated at phenol-acetone mega-complexes in Bohai-rim and Yangtze regions, with very little merchant cumene trade. UN 1918, IMDG Class 3 Packing Group III flammable; ships in stainless T11 ISO tanks for bulk. US imports do not carry Section 301 on bulk cumene at the time of writing. This cluster aggregates CAS 98-82-8 across the regulatory matrix. The merchant trade lane is thin because cumene production is almost always captive to a downstream phenol plant on the same site.
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Ethylbenzene
乙苯
Ethylbenzene is the precursor to styrene monomer via the dehydrogenation route. Over 99 percent of global ethylbenzene production feeds styrene; merchant trade is thin and dominated by captive intra-complex transfers. Chinese capacity is integrated at every major styrene complex in Zhejiang, Liaoning, and the Yangtze River chemical zones. UN 1175, IMDG Class 3 Packing Group II flammable; ships in stainless T11 ISO tanks for bulk. IARC Group 2B classification (possibly carcinogenic) drives stricter receiver-side handling. US imports do not carry Section 301 on bulk ethylbenzene at the time of writing. This cluster aggregates CAS 100-41-4 across the regulatory matrix.
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Cyclohexane
环己烷
Cyclohexane is the precursor to adipic acid (Nylon-6,6 chain) and caprolactam (Nylon-6 chain). Chinese capacity sits at integrated benzene-hydrogenation complexes in Bohai-rim and Yangtze River chemical zones. UN 1145, IMDG Class 3 Packing Group II flammable; ships in stainless T11 ISO tanks for bulk and 200 kg HDPE drums for sample volume. The low flashpoint at minus 18 degrees Celsius drives strict no-spark loading discipline. US imports do not carry Section 301 on bulk cyclohexane at the time of writing. This cluster aggregates CAS 110-82-7 across the regulatory matrix. The merchant trade lane is dominated by short-haul Asia movements feeding Nylon-6 caprolactam plants and Nylon-6,6 adipic-acid plants.
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Aniline (aminobenzene)
苯胺
Aniline is the precursor to MDI (methylene diphenyl diisocyanate) for polyurethane foam and elastomer production, and a feedstock for rubber chemicals and dyes. Chinese capacity is integrated at MDI mega-complexes (Wanhua, BASF, Covestro) in Yantai, Shanghai, and Ningbo. UN 1547, IMDG Class 6.1 Packing Group II for the inhalation and dermal toxicity; ships in stainless T11 ISO tanks for bulk. The methaemoglobinaemia toxicity profile drives strict receiver-side handling and PPE requirements. US imports do not carry Section 301 on bulk aniline at the time of writing. This cluster aggregates CAS 62-53-3 across the regulatory matrix.
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Bisphenol A (BPA)
双酚A
Bisphenol A is the precursor to polycarbonate resin, epoxy resin, and a wide range of phenolic intermediates. Chinese capacity has grown rapidly with the polycarbonate chain expansion; Chiu Shun, Wanhua, Sinopec, and Yangtze River complexes hold the bulk of capacity. UN 3077 if classified as environmentally hazardous in solid form, otherwise non-dangerous-goods for the solid flake or pellet. Ships in 25 kg PE bags or 1 t big bags. The EU REACH SVHC listing for endocrine-disruptor concerns drives downstream consumer-product reformulation pressure; verify against the ECHA SVHC candidate list before invoicing EU shipments. US imports do not carry Section 301 on bulk BPA at the time of writing. This cluster aggregates CAS 80-05-7 across the regulatory matrix.
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Methyl methacrylate (MMA)
甲基丙烯酸甲酯
Methyl methacrylate is the monomer for PMMA acrylic sheet and resin, surface coatings, and adhesives. Chinese capacity has more than doubled since 2018 with the C3 (propylene) and C4 (isobutylene) on-purpose routes overtaking the legacy acetone-cyanohydrin route. UN 1247, IMDG Class 3 Packing Group II flammable with the methacrylate inhibitor MEHQ at the spec rate; ships in stainless T11 ISO tanks for bulk. Polymerisation risk in the tank is the dominant cargo-loss mode for any shipment exceeding 60 days from production. US imports do not carry Section 301 on bulk MMA at the time of writing. This cluster aggregates CAS 80-62-6 across the regulatory matrix.
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Acrylic acid
丙烯酸
Acrylic acid is the precursor for super-absorbent polymers (SAP), acrylate ester production (for coating, adhesive, and textile applications), and water-treatment polymers. Chinese capacity is dominated by the propylene-oxidation route at Bohai-rim and Yangtze River petrochemical complexes; Sanmu, Wanhua, and Sinopec hold the bulk of capacity. UN 2218, IMDG Class 8 Packing Group II for the corrosivity, with the additional polymerisation risk requiring inhibitor (MEHQ) at the spec rate. Ships in stainless T11 ISO tanks for bulk. US imports do not carry Section 301 on bulk acrylic acid at the time of writing. This cluster aggregates CAS 79-10-7 across the regulatory matrix.
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Methylene diphenyl diisocyanate (MDI)
二苯基甲烷二异氰酸酯
MDI is the dominant polyurethane isocyanate for rigid foam (insulation, refrigeration), elastomer, coating, and adhesive applications. Chinese capacity dominates globally with Wanhua as the largest single producer; capacity sits at Yantai, Ningbo, and the Bohai-rim and Yangtze River complexes. UN 2489, IMDG Class 6.1 Packing Group III for the inhalation sensitisation profile; ships in heated stainless T11 ISO tanks or 220 kg drums for sample volume. The reactive isocyanate chemistry demands strict moisture exclusion in storage and handling; any water ingress triggers CO2 evolution and pressure build. US imports do not carry Section 301 on bulk MDI at the time of writing. This cluster aggregates CAS 101-68-8 across the regulatory matrix.
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Toluene diisocyanate (TDI)
甲苯二异氰酸酯
TDI is the second polyurethane isocyanate (after MDI), dominant in flexible foam (mattress, upholstery, automotive seating). Chinese capacity is dominated by Wanhua, Cangzhou Dahua, and Covestro Shanghai; the 80:20 toluene-diisocyanate-isomer-mix grade is the flexible-foam standard, the 65:35 mix serves elastomer applications. UN 2078, IMDG Class 6.1 Packing Group II for the highest-tier inhalation toxicity classification a routine polyurethane intermediate carries; ships in heated stainless T11 ISO tanks or 220 kg drums for sample volume. The OSHA PEL on TDI exposure is the strictest of any routine commodity chemical. US imports do not carry Section 301 on bulk TDI at the time of writing. This cluster aggregates CAS 26471-62-5 across the regulatory matrix.
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Hydrofluoric acid (HF)
氢氟酸
Hydrofluoric acid is a high-purity etchant for semiconductor processing, glass etching, and fluoropolymer precursor production. Chinese capacity is dominated by fluorspar-acidulation plants in Jiangxi, Fujian, and Inner Mongolia. UN 1790, IMDG Class 8 Packing Group I for the highest-tier corrosivity and inhalation toxicity, with secondary risk 6.1; ships in PE-lined or PFA-lined ISO tanks and HDPE drums. The bone-seeking calcium-chelation toxicity profile and the severe dermal burns risk drive the highest-tier receiver-side handling and emergency-response protocols. Semiconductor-grade HF carries a sub-ppt metals spec that commands a substantial premium over technical-grade. US imports do not carry Section 301 on bulk HF at the time of writing. This cluster aggregates CAS 7664-39-3 across the regulatory matrix.
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Nitric acid
硝酸
Nitric acid is a feedstock for ammonium nitrate fertiliser, adipic acid (Nylon-6,6 chain), TDI nitration, and a broad range of nitration chemistry. Chinese capacity is integrated at ammonia-derivative complexes in Henan, Shandong, and the Bohai-rim chemical zones via the Ostwald process. UN 2031 for the 65 to 70 percent grade, UN 2032 for red fuming nitric acid; IMDG Class 8 Packing Group II for the typical 65 percent commercial grade, with secondary risk 5.1 (oxidiser). Ships in stainless or PTFE-lined ISO tanks; ferrous metal contact is the dominant tank-corrosion failure mode. US imports do not carry Section 301 on bulk nitric acid at the time of writing. This cluster aggregates CAS 7697-37-2 across the regulatory matrix.
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Phosphoric acid
磷酸
Phosphoric acid is the precursor to DAP and MAP fertiliser, food-grade phosphate salts, and a wide range of pharma and industrial phosphate chemistry. Chinese capacity is dominated by Yunnan, Guizhou, and Hubei phosphate-rock-acidulation complexes; the wet-process is the volume route, thermal-process serves food and electronic grades. UN 1805, IMDG Class 8 Packing Group III for the 75 to 85 percent commercial grade; ships in stainless, PE-lined, or rubber-lined ISO tanks. The food-grade and electronic-grade specifications carry separate certifications and a meaningful price premium. US imports do not carry Section 301 on bulk phosphoric acid at the time of writing. This cluster aggregates CAS 7664-38-2 across the regulatory matrix.
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Ammonia (anhydrous)
液氨
Anhydrous ammonia is the precursor to urea, ammonium nitrate, ammonium sulfate, nitric acid, and the broader nitrogen-fertiliser and nitrogen-derivative chain. Chinese capacity is the largest globally, dominated by coal-gasification plants in Inner Mongolia, Shanxi, and Shandong, plus natural-gas reforming on the south-eastern coast. UN 1005, IMDG Class 2.3 (toxic gas) plus 8 (corrosive); ships in dedicated stainless T50 pressure ISO tanks under refrigeration or pressurised. The inhalation toxicity profile drives the highest-tier receiver-side handling and emergency-response protocols. US imports do not carry Section 301 on bulk ammonia at the time of writing, though the broader nitrogen-fertiliser tariff context shifts with USITC review cycles. This cluster aggregates CAS 7664-41-7 across the regulatory matrix.
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Chlorine (Cl2)
氯气
Chlorine is the chlor-alkali co-product with caustic soda and the upstream feedstock for HCl, PVC, EDC, propylene oxide, chlorinated solvents, and the broader chlorine-derivative chain. Chinese capacity is integrated at every major chlor-alkali complex in Shandong, Jiangsu, Inner Mongolia, and the Yangtze River chemical zones. UN 1017, IMDG Class 2.3 (toxic gas) plus 5.1 (oxidiser) plus 8 (corrosive); ships in dedicated stainless T50 pressure ISO tanks or specialised rail-tank cars on shorter inland routes. Merchant cross-border chlorine trade is minimal; most production is captive intra-complex. The Bhopal-class toxicity profile drives the highest-tier receiver-side handling and emergency-response protocols. This cluster aggregates CAS 7782-50-5 across the regulatory matrix and the substance-level CAS reference.