双语化学辞典Chem Lexicon
反应 · 化工 · 煤化工与天然气化工 Chemical industry · Coal and gas conversion

费托合成Fischer–Tropsch process

拼音Pinyin fèi tuō hé chéng　别名Also 费-托合成；F-T 合成；Fischer–Tropsch synthesis； FT synthesis

定义Definition

费托合成是在铁或钴催化剂上把合成气（CO 与 H₂ 的混合物）转化为长链烃（及少量含氧化合物）的反应，用于由煤、天然气或生物质生产合成燃料和蜡。

The Fischer–Tropsch process converts synthesis gas (a mixture of CO and H₂) over iron or cobalt catalysts into long-chain hydrocarbons (plus some oxygenates), producing synthetic fuels and waxes from coal, natural gas or biomass.

反应与机理Reaction and mechanism

主反应 nCO + (2n+1)H₂ → CₙH₂ₙ₊₂ + nH₂O，强放热。一般认为 CO 在金属表面解离，生成表面 CH₂ 物种，逐个插入链中（表面聚合），链增长概率 α 决定产物碳数分布，服从安德森-舒尔茨-弗洛里（ASF）分布。

Main reaction nCO + (2n+1)H₂ → CₙH₂ₙ₊₂ + nH₂O, strongly exothermic. CO is thought to dissociate on the metal, forming surface CH₂ units that add one by one (surface polymerisation); the chain-growth probability α sets the carbon-number distribution, which follows the Anderson–Schulz–Flory law.

由来Origin

德国凯撒·威廉煤炭研究所的弗朗茨·费歇尔和汉斯·托罗普施于 1925 年开发。二战期间德国用于生产合成燃料；南非萨索尔公司自 1955 年起大规模应用，卡塔尔“珍珠”项目以天然气为原料（GTL）。

Developed in 1925 by Franz Fischer and Hans Tropsch at the Kaiser Wilhelm Institute for Coal Research. Germany used it for synthetic fuel in World War II; South Africa's Sasol has run it at scale since 1955, and Qatar's Pearl plant converts natural gas (GTL).

催化剂与工艺Catalysts and operation

铁催化剂便宜、具有水煤气变换活性，适合 H₂/CO 比低的煤基合成气；钴催化剂活性高、寿命长，适合天然气基合成气。低温（200–240 °C）多产柴油和蜡，高温（300–350 °C）多产汽油和烯烃。产品几乎不含硫和芳烃。

Iron is cheap and has water-gas-shift activity, suiting low-H₂/CO coal-derived gas; cobalt is more active and long-lived, suiting gas-derived syngas. Low-temperature operation (200–240 °C) favours diesel and wax, high temperature (300–350 °C) gasoline and olefins. Products are essentially free of sulfur and aromatics.

反应Reactions

n CO + (2n+1) H2 ⟶ CₙH2ₙ₊2 + n H2O

Fe 或 Co 催化剂，200–350 °C，10–40 atm

Fe or Co catalyst, 200–350 °C, 10–40 atm

  1. CO 与 H₂ 在金属表面吸附，CO 解离或氢助解离。

    CO and H₂ adsorb; CO dissociates directly or H-assisted.

  2. 形成表面 CHₓ 单元并逐步插入增长链。

    Surface CHₓ units form and insert into growing chains.

  3. 链通过加氢或 β-H 消除脱附为烷烃或烯烃。

    Chains desorb by hydrogenation or β-H elimination as alkanes or alkenes.

CO + 2 H2 ⟶ –CH2– + H2O　ΔH ≈ −165 kJ/mol

每增加一个链节放热约 165 kJ。

Each chain unit releases about 165 kJ.

年表Timeline

  • 1925

    费歇尔与托罗普施发明该方法

    Fischer and Tropsch invent the process

  • 1936

    德国首座工业装置投产

    First German commercial plant

  • 1955

    南非萨索尔投产

    Sasol begins production in South Africa

  • 2011

    卡塔尔珍珠 GTL 全面运行

    Qatar's Pearl GTL reaches full operation