四氢呋喃 Tetrahydrofuran (THF)

四氢呋喃（Tetrahydrofuran，分子式 C4H8O，(CH2)4O，简称 THF）是含氧五元杂环醚，常温下为无色透明、易挥发、具乙醚气味的液体，能与水及乙醇、乙醚、丙酮、苯、氯仿、烃类等多数有机溶剂任意比例混溶（与水完全混溶）。因其液态范围宽、极性适中且对树脂渗透性好，素有“万能溶剂”之称，是常用的中等极性非质子性溶剂。

Tetrahydrofuran (C4H8O, (CH2)4O, THF) is an oxygen-containing five-membered cyclic ether; a colorless, volatile, mobile liquid with an ether-like odour at room temperature, miscible with water and with ethanol, ether, acetone, benzene, chloroform and most organic solvents (fully miscible with water). With a wide liquid range and moderate polarity plus good substrate penetration, it is known as a 'universal solvent' and a common medium-polarity aprotic solvent.

其主要用途极广：高分子工业中用作 PVC、聚偏氯乙烯、聚醚型聚氨酯等的反应溶剂与加工助剂；医药与精细化工中用作合成抗菌药（头孢类）、激素类、维生素 E 等的中间体；格氏试剂、有机锂试剂等有机金属反应的优选溶剂；锂离子电池电极浆料溶剂；色谱分析、萃取与天然产物分离的溶剂；亦用于制造聚四氢呋喃（PTMEG，氨纶/聚氨酯弹性体原料）、γ-丁内酯、丁二烯等。性能上兼具醚的溶解力与相对较高的极性，对有机金属试剂稳定（需除氧、无水）。

Principal uses are very broad: in polymers as reaction solvent/processing aid for PVC, PVDC, polyether-type polyurethanes; in pharma and fine chemicals as intermediate for cephalosporins, steroids, vitamin E; preferred solvent for Grignard, organolithium and other organometallic reactions; cathode/anode slurry solvent for Li-ion batteries; chromatography, extraction and natural-product isolation; also to make polytetramethylene ether glycol (PTMEG for spandex/PU elastomers), gamma-butyrolactone, butadiene. Combines ether solvency with moderate polarity and stability toward organometallics (under oxygen-free, anhydrous conditions).

CAS 登记号 CAS No.

109-99-9

分子式 Molecular formula

C4H8O（(CH2)4O）

分子量 Molecular weight

72.11 g/mol

EC 号 EC / EINECS

203-726-8

EC Index 号

603-025-00-0

RTECS 号

LU5950000

MDL 号

MFCD00005356

PubChem CID

8028（经 PubChem 按 CAS 109-99-9 核验

verified via PubChem by CAS 109-99-9）

HS 编码 HS Code

29321100（中国 8 位，其他内酯；10 位常见 2932110000

China 8-digit 29321100; 10-digit commonly 2932110000）

UN 编号 / 危险类别 UN / Class

UN 2056（TETRAHYDROFURAN），第 3 类易燃液体，包装类别 II（PG II）/ UN 2056, Class 3 flammable liquid, Packing Group II

中国危险货物编号 China DG No.

31042，第 3.1 类低闪点易燃液体

31042, Class 3.1 low-flash flammable liquid

别名 Synonyms

四氢呋喃；THF；1,4-环氧丁烷；氧杂环戊烷；氧戊环；oxolane；tetramethylene oxide；butylene oxide

项目 Item

指标 Specification

测试方法 Test Method

四氢呋喃含量 Assay (GC)

>= 99.95 %（工业优等品）；>= 99.5 %（试剂 AR）/ >=99.95% (industrial premium); >=99.5% (reagent AR)

GC

外观 Appearance

无色透明液体，无可见杂质 / Colorless clear liquid, free of visible impurities

Visual

色度 Color (APHA/Hazen)

≤ 5（工业优等品）；≤ 10（试剂/一等品）

GB/T 3143 / ASTM D1209

水分 Water (KF)

≤ 0.02 %（工业优等品）；≤ 0.05 %（试剂）

GB/T 6283 / ASTM E1064

过氧化物 Peroxide (as H2O2)

≤ 0.01 %（工业优等品，以 H2O2 计）；≤ 0.015 %（试剂）

Iodometric / GB/T

酸度 Acidity (as acetic acid)

≤ 0.002 %（工业优等品）；≤ 0.005 %（试剂，以乙酸计）

Titration

蒸发残渣 Evap. residue

≤ 0.005 %（工业优等品）；≤ 0.01 %（试剂）

GB/T 6324.2

密度 Density (20 °C)

0.886 – 0.889 g/cm3（20/4 ℃）

GB/T 4472 / ASTM D4052

沸程 Boiling range

65 – 67 °C（典型 65.5 – 66 °C）

GB/T 7534 / ASTM D1078

稳定剂 Stabilizer (BHT)

约 100 – 250 ppm（抗氧/阻聚，防止过氧化物生成）/ ~100-250 ppm (antioxidant, peroxide inhibition)

GC / HPLC

分子式 Molecular formula

C4H8O（(CH2)4O）

分子量 Molecular weight

72.11 g/mol（精确质量 72.058）

外观 Appearance

无色透明、易挥发液体，具乙醚气味，易燃

Colorless, volatile liquid, ether-like odour, flammable

熔点 / 凝固点 Melting point

约 −108.5 °C（文献 −108.4 ~ −108.5 °C；Sigma/Merck 记 −108 °C）/ ~−108.5 C; lit. −108.4 to −108.5 C

沸点 Boiling point

约 66 °C（常压；文献 65 – 67 °C；ICSC 记 66 °C）/ ~66 C at 760 mmHg; lit. 65-67 C

密度 Density

0.889 g/mL（25 °C；Sigma/Merck）；0.89 g/cm3（20 °C；Merck Millipore/INVISTA）；范围 0.886–0.889

相对蒸气密度 Vapor density (air=1)

约 2.5（比空气重

heavier than air）

蒸气压 Vapor pressure

约 19.3 kPa（145 mmHg）@ 20 °C；114 mmHg @ 15 °C；170 hPa（Merck Millipore）@ 20 °C

闪点 Flash point

约 −14 °C（闭杯；实测/各厂记载 −14 ~ −21 °C；Sigma/Merck 记 −21.2 °C 闭杯，ICSC 记 −14 °C 闭杯，INVISTA TCC −20 °C）/ ~−14 C (closed cup; range −14 to −21 C; Sigma/Merck −21.2 C c.c., ICSC −14 C c.c., INVISTA TCC −20 C)

自燃温度 Auto-ignition temp.

约 321 °C（≈610 °F；Sigma/Merck/PubChem/INVISTA/DuPont/ICSC 制造商主流共识；注：Merck Millipore LiChrosolv 与个别中文 MSDS 列 215–230 °C，文献存在差异

~321 C (610 F); manufacturer mainstream consensus; NOTE: Merck Millipore LiChrosolv and a few Chinese MSDS list 215-230 C - literature discrepancy)

爆炸极限 Explosive limits (air)

下限约 1.5 %（体积），上限约 12.4 %（体积）（Merck Millipore/ICSC；Sigma 记 1.8–11.8 %）/ LEL ~1.5% v/v, UEL ~12.4% v/v (Merck Millipore/ICSC; Sigma 1.8-11.8%)

折射率 Refractive index (n20/D)

1.407（文献 1.405 – 1.407）

分配系数 log P (辛醇/水)

约 0.5（XLogP3 计算值；ICSC/实验 log Kow 约 0.46）/ ~0.5 (XLogP3; exp. log Kow ~0.46)

粘度 Viscosity

约 0.48 – 0.53 mPa·s（20 °C）

溶解度 Solubility

与水完全混溶（任意比例）；溶于乙醇、乙醚、丙酮、苯、氯仿、烃类等多种有机溶剂

Completely miscible with water (any ratio); soluble in ethanol, ether, acetone, benzene, chloroform, hydrocarbons

介电常数 Dielectric constant

约 7.5（20 °C）

临界温度 Critical temp.

约 268 °C（临界压力约 5.19 MPa）

对水危害等级 WGK

1（德国；Merck/Sigma/ChemicalBook/ICSC/guidechem 等所有来源一致为 WGK 1，无冲突

1 (Germany); all sources agree WGK 1 - no conflict）

致癌性 IARC

2B 类（2017-10-27 列入，可能对人类致癌；对应 GHS Carc. 2

H351）/ Group 2B (listed 2017-10-27, possibly carcinogenic; corresponds to GHS Carc. 2 / H351)

高分子与材料：PVC、聚偏氯乙烯、聚醚型聚氨酯等聚合/加工的反应溶剂与助剂；聚四氢呋喃（PTMEG）原料（氨纶、弹性体）。

Polymers & materials: reaction solvent/auxiliary for PVC, PVDC, polyether-type PU polymerization/processing; feedstock for polytetramethylene ether glycol (PTMEG, spandex, elastomers).

医药与精细化工：头孢菌素、激素、维生素 E 等合成中间体；格氏/有机锂等有机金属反应的优选溶剂；色谱与萃取溶剂。

Pharma & fine chemicals: intermediate for cephalosporins, steroids, vitamin E; preferred solvent for Grignard/organolithium organometallic reactions; chromatography and extraction solvent.

新能源与电子：锂离子电池电极浆料溶剂（需高纯、无水、低杂质）；精密清洗与表面处理。

Energy & electronics: Li-ion battery electrode slurry solvent (high-purity, anhydrous, low-impurity required); precision cleaning and surface treatment.

阴凉、通风、干燥、防爆库房；远离火种、热源与引火源，库温不宜超过 30 °C（建议更低），密封、避光保存。按第 3 类易燃液体管理，使用防爆型照明与通风，禁用易产生火花的设备与工具，容器与管线须可靠接地/跨接防静电。THF 蒸气比空气重，易在低处积聚并远距离扩散，须特别注意地沟、地下室等低位空间的通风与防爆。可与水混溶，但大量泄漏仍须用砂土/不燃吸附材料收容后处理。

Store in a cool, well-ventilated, dry, explosion-proof area; away from ignition, heat; warehouse temp. preferably <= 30 C (lower recommended), keep sealed and away from light. Managed as Class 3 flammable liquid; explosion-proof lighting/ventilation, no sparking equipment/tools, bond/ground containers and piping. Vapour is heavier than air and can accumulate low and travel far - pay special attention to ventilation/explosion protection in low spaces (drains, basements). Miscible with water but large spills still need containment with sand/non-combustible absorbent.

⚠ 过氧化物防控（最重要）：THF 在空气中、光照下或接触某些金属时可生成爆炸性过氧化物，务必采购含稳定剂（BHT 等）的产品，密封、避光、低温、氮气保护储存；长期存放或任何蒸馏/浓缩前必须做过氧化物检测（碘量法或淀粉-碘化钾试纸），合格方可进行；严禁蒸干；出现浑浊/变色/固体立即按含过氧化物危废处置。

⚠ PEROXIDE CONTROL (MOST IMPORTANT): THF forms explosive peroxides in air, light or on contact with certain metals - procure stabilized (BHT etc.) product, store sealed, dark, cool, preferably under nitrogen; test for peroxides (iodometry or starch-KI paper) before any long storage or distillation/concentration and only proceed if within limits; NEVER distill to dryness; cloudiness/discoloration/solids => dispose as peroxide-containing hazardous waste.

操作人员须佩戴防护眼镜、防毒（有机蒸气）口罩、耐溶剂手套（丁腈等）与防护服，在通风良好处作业，避免皮肤/眼睛接触与吸入蒸气。THF 刺激眼睛与呼吸道（H319/H336）、低毒（H302），高浓度蒸气有中枢神经麻醉作用，IARC 2B（疑似致癌）。皮肤接触用大量清水冲洗；眼睛接触用清水冲洗至少 15 分钟并就医；吸入移至空气新鲜处，必要时就医；切勿催吐。工作现场禁止吸烟、进食和饮水，工后更衣。

Operators wear goggles, organic-vapour respirator, solvent-resistant gloves (nitrile) and protective clothing; work in well-ventilated areas; avoid skin/eye contact and vapour inhalation. THF irritates eyes and respiratory tract (H319/H336), low-toxicity (H302), high vapour narcotic to CNS, IARC 2B (suspected carcinogen). Wash skin with plenty of water; flush eyes >=15 min and seek care; move to fresh air if inhaled; do NOT induce vomiting. No smoking/eating/drinking on site; change clothes after work.

禁忌：与强氧化剂（硝酸、高锰酸钾、过氧化物、浓硝酸等）、强酸、强碱、卤素分开存放，切忌混储；与强氧化剂接触可发生剧烈反应甚至爆炸。与氢氧化钾、氢氧化钠等强碱反应剧烈。避免与空气、光、某些金属（钠、钾、铝）长期接触以防过氧化物累积。

Incompatibilities: segregate from strong oxidizers (nitric acid, permanganate, peroxides, conc. nitric), strong acids, strong bases, halogens; violent reaction/explosion on contact with strong oxidizers. Reacts vigorously with KOH, NaOH. Avoid prolonged contact with air, light, certain metals (Na, K, Al) to prevent peroxide build-up.

桶装：通常 180 kg/桶（200 L 铁桶/镀锌桶）等常见规格；亦可用钢桶。

Drum: commonly 180 kg/drum (200 L iron/galvanized drum); steel drum also used.

IBC 吨桶 / ISO 罐 / 散装：可按客户需求提供（须为耐溶剂材质，如不锈钢、碳钢衬里、HDPE 衬里，且须防静电、接地）。

IBC tote / ISO tank / bulk: available on request (solvent-resistant material such as stainless steel, lined carbon steel, HDPE-lined, with static protection/grounding).

注意：属第 3 类易燃液体（UN 2056，PG II，低闪点），须使用符合 UN 包装要求的容器并张贴第 3 类易燃标识；具体按目的国法规与承运人要求。

Note: Class 3 flammable liquid (UN 2056, PG II, low-flash) - use UN-compliant packaging and affix Class 3 flammable labels; per destination regulation and carrier.

在原包装、密闭、阴凉通风（≤ 30 °C，且建议更低、避光、远离热源与火种）条件下，建议保质期 12 个月（含稳定剂产品）；THF 极易挥发、易氧化生成过氧化物，开封后宜尽快使用并密封、氮气保护保存，每次使用前或长期存放后须复检过氧化物与水分，必要时重新蒸馏（严禁蒸干）并补加稳定剂。

Recommended shelf life 12 months under original sealed packaging, cool and dry (<= 30 C, lower recommended, away from light, heat, ignition) for stabilized product. THF is very volatile and readily oxidizes to peroxides; use promptly after opening, keep sealed under nitrogen, re-test for peroxides and water before each use or after long storage, re-distill if needed (never to dryness) and replenish stabilizer.

GHS 危险性分类（Sigma-Aldrich/Merck、Merck Millipore、ChemicalBook、ICSC、ECHA C&L 库存主流共识）：易燃液体 2 类 H225（高度易燃液体和蒸气）；急性毒性 4 类 H302（吞咽有害）；眼刺激 2 类 H319（造成严重眼刺激，部分 SDS 列眼损伤 1 类 H318）；特异性靶器官毒性-一次接触 3 类 H335（呼吸道刺激）+ H336（嗜睡/头晕）；致癌性 2 类 H351（疑似致癌，对应 IARC 2B）。象形图：GHS02（火焰）+ GHS07（感叹号）+ GHS08（健康危害）。信号词 危险/Danger。补充危害 EUH019（可能形成爆炸性过氧化物）。

GHS classification (Sigma-Aldrich/Merck, Merck Millipore, ChemicalBook, ICSC, ECHA C&L Inventory mainstream consensus): Flam. Liq. 2 H225 (highly flammable liquid and vapour); Acute Tox. 4 H302 (harmful if swallowed); Eye Irrit. 2 H319 (serious eye irritation, some SDS Eye Dam. 1 H318); STOT SE 3 H335 (respiratory irritation) + H336 (drowsiness/dizziness); Carc. 2 H351 (suspected carcinogen, IARC 2B). Pictograms: GHS02 (flame) + GHS07 (exclamation) + GHS08 (health hazard). Signal word Danger. Supplementary EUH019 (may form explosive peroxides).

⚠ 高度易燃（最重要）：闪点约 −14 °C（闭杯，实测低至 −21 °C），远低于室温，常温下即可被点燃；蒸气与空气形成爆炸性混合物（爆炸极限约 1.5 %–12.4 %），自燃温度约 321 °C。远离开火、高热与强氧化剂；储存使用防爆电气，容器管线接地防静电，保持通风。灭火用抗溶泡沫、干粉、二氧化碳或砂土（水无效），消防人员须在上风向、佩戴防毒面具。

⚠ Highly flammable (MOST IMPORTANT): flash point ~-14 C (c.c., measured as low as -21 C), far below room temperature, ignites at ambient; vapour forms explosive mixtures with air (explosive limits ~1.5%-12.4%), autoignition ~321 C. Keep from ignition, high heat and strong oxidizers; explosion-proof electrical, bonded/grounded containers, ventilated. Extinguish with alcohol-resistant foam, dry powder, CO2 or sand (water ineffective); firefighters upwind with respirators.

⚠ 过氧化物爆炸风险（THF 特有）：THF 为环状醚，长期接触空气/光/某些金属可生成对热和冲击敏感的过氧化物，浓缩或蒸干时可能爆炸。任何蒸馏/浓缩前须过氧化物检测合格；严禁蒸干；商品须含稳定剂并妥善保存。

⚠ Peroxide explosion risk (THF-specific): as a cyclic ether THF forms heat/shock-sensitive peroxides on prolonged air/light/metal contact; may explode when concentrated or distilled to dryness. Test peroxides before any distillation/concentration; never distill to dryness; keep stabilized product properly stored.

眼/呼吸道刺激与低毒：H319 严重眼刺激、H335/H336 吸入致呼吸道刺激与嗜睡头晕，H302 吞咽有害；避免吸入蒸气或接触皮肤眼睛。急性毒性总体较低：LD50 大鼠经口约 2816 mg/kg（研究范围约 2500–3000 mg/kg），LD50 大鼠吸入 LC50 约 61740 mg/m3（3 小时）；高浓度蒸气有中枢神经麻醉作用。IARC 2B 类（疑似致癌），操作时做好职业防护与通风。

Eye/respiratory irritation & low toxicity: H319 serious eye irritation, H335/H336 respiratory irritation and drowsiness, H302 harmful if swallowed; avoid vapour inhalation and contact. Overall low acute toxicity: LD50 rat oral ~2816 mg/kg (study range ~2500-3000 mg/kg), LD50 rat inhalation LC50 ~61740 mg/m3 (3 h); high vapour narcotic to CNS. IARC Group 2B (suspected carcinogen) - use PPE and ventilation.

运输信息 Transport：UN 2056（TETRAHYDROFURAN），第 3 类易燃液体，包装类别 II（PG II），中国危险货物编号 31042（第 3.1 类低闪点易燃液体）。须使用 UN 认证包装、张贴第 3 类易燃标识，海运/空运/公路分别符合 IMDG/IATA/ADR 要求；具体以目的国法规与承运人判定为准。

Transport: UN 2056 (TETRAHYDROFURAN), Class 3 flammable liquid, Packing Group II (PG II), China DG No. 31042 (Class 3.1 low-flash flammable liquid). Use UN-certified packaging and Class 3 labels; comply with IMDG/IATA/ADR as applicable; per destination regulation and carrier.

法规 Regulatory：列入中国《危险化学品目录(2015版)》序号 2071（四氢呋喃），危险货物编号 31042（第 3.1 类）。经多源核实不属于易制爆、重点监管、监控化学品或特别管控化学品；且 NOT 列入国务院《易制毒化学品管理条例》(第445号) 第一/二/三类目录，国家层面不属列管易制毒（出口无需国家级易制毒出口许可证），但部分省份列为“非列管制毒化学品”禁毒监测，出口宜做终端用途尽职调查。美国 TSCA 已列；欧盟 REACH 已注册（Active）。出口须提供商检与合规 SDS/标签。

Regulatory: listed in China's at entry No. 2071 (tetrahydrofuran), China DG No. 31042 (Class 3.1). Verified NOT explosively-unstable / key-supervised / monitored / specially-controlled; and NOT in the State Council three-category list - not a nationally-controlled precursor (no national precursor export licence needed), but some provinces list it in 'non-controlled drug-precursor' anti-drug monitoring - perform end-use due diligence for export. US TSCA listed; EU REACH registered (Active). Export requires commodity inspection and compliant SDS/labels.

NFPA 704：健康 2 / 易燃 3 / 反应 1（反应/不稳定项反映过氧化物生成风险 / H 2 / F 3 / R 1, reactivity reflects peroxide-formation risk）。

NFPA 704: Health 2 / Flammability 3 / Reactivity 1 (H 2 / F 3 / R 1, reactivity reflects peroxide-formation risk).