Sublimation Technique
Sublimation Technique - Related Videos
05:39
Purification of Ferrocene by Sublimation
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2023
Source: Tamara M. Powers, Department of Chemistry, Texas A&M University Sublimation, the direct phase transition of a solid into a gas without first becoming a liquid, takes place at temperatures and pressures lower than that of the compound's triple point (Figure 1).The process of sublimation can be utilized to purify both organic and inorganic solids. During the purification technique, a solid is heated directly into the gas-phase. All non-volatile impurities are left behind while the...
02:33
Phase Transitions: Sublimation and Deposition
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2020
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
01:03
Sublimation
0 Views •
2024
Sublimation is the direct transformation of a solid to a gaseous state. For instance, at standard pressure and room temperature, solid carbon dioxide sublimes to gaseous carbon dioxide. The phase diagram depicts the conditions required for sublimation. This process occurs at the solid-gas phase boundary and is not observed above the triple point of the substance. The reverse of sublimation is called deposition, where a gaseous substance condenses directly into a solid. Sublimation and...
08:36
Sublimation of DAN Matrix for the Detection and Visualization of Gangliosides in Rat Brain Tissue for MALDI Imaging Mass Spectrometry
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Cited by 43 •
2017
A protocol for the sublimation of DAN matrix onto rat brain tissue for the detection of gangliosides using MALDI Imaging Mass Spectrometry is presented.
12:21
Close-Space Sublimation-Deposited Ultra-Thin CdSeTe/CdTe Solar Cells for Enhanced Short-Circuit Current Density and Photoluminescence
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Cited by 6 •
2020
This work describes the complete fabrication process of thin absorber cadmium selenium telluride/cadmium telluride photovoltaic devices for enhanced efficiency. The process utilizes an automated in-line vacuum system for close-space sublimation deposition that is scalable, from fabrication of small area research devices as well as large-scale modules.
FAQs
The key selection criterion is a volatility contrast: the desired solid must be sufficiently volatile, while accompanying impurities should be less volatile or nonvolatile. Controlled heating then preferentially transfers the target into the vapor phase. This contrast allows purification without requiring the impurities to undergo the same phase change, making the method useful for isolating a cleaner solid.
Reduced pressure and controlled heating provide conditions that promote vaporization of the selected solid while limiting unnecessary thermal exposure. Their use helps control how readily the target compound enters the vapor phase and travels through the apparatus. Careful control is therefore important when assessing a compound’s volatility and thermal behavior during purification.
The cooler surface provides a location where the vaporized compound re-forms as a solid. Because the target compound is collected there while less volatile or nonvolatile impurities remain behind, deposition separates the recovered material from much of the original mixture. The resulting solid can then be collected as crystalline material for further analysis or synthesis.
A typical sequence begins by placing the solid mixture in the apparatus, applying controlled heating or reduced pressure, and allowing the volatile component to travel away from the heated material. The vapor then reaches a cooler surface, where it deposits as a solid. The collected crystalline material is separated from the impurities left behind.
Chemists choose this approach when the desired compound is volatile enough to vaporize under controlled conditions and the impurities are less volatile or nonvolatile. It is especially relevant when the goal is to recover a purified solid while leaving unsuitable components behind. The method also provides information about whether a compound displays useful volatility and thermal behavior.
Beyond producing purified material, the process can help chemists evaluate a compound’s volatility and response to controlled heating. Recovery of crystalline solid supports subsequent analysis or use in synthesis. In this way, the technique serves both as a practical purification method for suitable organic compounds and as a way to examine their physical behavior.