vacuum distillation

chemical process

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July 14, 2026

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Vacuum distillation is a chemical process used to separate liquids that have high boiling points or tend to decompose at atmospheric pressure. By reducing the pressure within the distillation apparatus, the boiling points of these substances are lowered, allowing them to vaporize and then condense at more manageable temperatures. This method is crucial in industries like petroleum refining, where it's used to process crude oil into various fractions such as lubricants and fuel oil, preventing thermal cracking of components. The process involves heating the liquid in a still, cooling the resulting vapor in a condenser, and collecting the purified liquid (distillate).123

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$Crude-oil fractional distillation column diagram$
distillation
This method, called vacuum distillation, is sometimes employed when dealing with substances that normally boil at inconveniently high temperatures or that decompose when boiling under atmospheric pressure. Steam distillation is an alternative method of achieving distillation at temperatures lower than the normal boiling point. It is applicable when…
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This method, called vacuum distillation, is sometimes employed when dealing with substances that normally boil at inconveniently high temperatures or that decompose when boiling under atmospheric pressure. Steam distillation is an alternative method of achieving distillation at temperatures lower than the normal boiling point. It is applicable when…
Read More

tin processing
Refining
Vacuum distillation is sometimes used in fire refining. In this process, molten tin is heated in a dense graphite vessel at high temperatures (1,100 to 1,300 °C, or 2,000 to 2,375 °F). A vacuum is applied, and impurities are removed by selective distillation at their…
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Vacuum distillation is sometimes used in fire refining. In this process, molten tin is heated in a dense graphite vessel at high temperatures (1,100 to 1,300 °C, or 2,000 to 2,375 °F). A vacuum is applied, and impurities are removed by selective distillation at their…
Read More

petroleum refining
Vacuum distillation
The principles of vacuum distillation resemble those of fractional distillation (commonly called atmospheric distillation to distinguish it from the vacuum method), except that larger-diameter columns are used to maintain comparable vapour velocities at reduced operating pressures. A vacuum of 50 to 100 mm…
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The principles of vacuum distillation resemble those of fractional distillation (commonly called atmospheric distillation to distinguish it from the vacuum method), except that larger-diameter columns are used to maintain comparable vapour velocities at reduced operating pressures. A vacuum of 50 to 100 mm…
Read More