Buchner Funnel

Used not necessarily in chemistry labs, but in scientific industries and labs too, a Buchner funnel is an efficient lab tool mainly used to filter liquid from solid. Well, on a personal note I am nowhere relatively close to the subject of 'chemistry', but so as to advance my knowledge apart from me basking in my own world of interest, I chose to write on this context.

What is a Buchner Funnel

Removing unwanted solids out of any fluids (liquids) is the basic job of this funnel. The mixture of the liquids and solids is passed through the filter, rather its passed through a tiny piece of filter paper which behaves as the filtering agent. It blocks the solid particles and the remains are passed into the collecting flask further ahead. On understanding basics you can relate a Buchner funnel to some typical kind of filter funnel equipment.

Setup and Structure

These funnels are fabricated out of a variety of materials like porcelain, plastic or glass. Speaking about the setup it's simple to read and imagine, in case you haven't seen one!

Setup: There is a Buchner flask made of glass which is placed on a flat table. Right on top of the Buchner flask is just another container with a modest hole in its bottom. This secondary container is placed on top of the flask gently. (the perforated hole is facing downwards, i.e., to the flask and the other hole is at the side).

In this elementary setup of the apparatus, the most important aspect gets introduced now. It is the 'piece of filter paper' which is a disguise to the entire idea of funnel. It's placed in between so that the solids get segregated from the fluids. At the side hole there is another vacuum constituent which totally sucks out the air of the flask.

Process: When a mixture is poured into the top container, due to the fitted filter paper into the top container, all the solid particles gets stuck in the filter. So once that happens, the liquid freely flows from the filter paper into the Buchner flask below.

Now that the process is quite clearly explained to you in short, let me brief you on the actual scene behind the curtains. The main advantage of learning how to use this funnel in your chemistry life must have really helped you to speed up with all your experiments and practical projects. Apart from the process discussed above, there are tiny things to keep in mind about the whole process. A: the filtration material (filter paper) should be moistened with a solvent prior to the usage or fixing of it in the container. This is to prevent the initial leakage. B: The pouring fluid which is to be filtered into another container is forced through a suction of vacuum. C: Also note that the solvent shouldn't exceed the necessary condition, else the extra too would get sucked into the vacuum suction.

Uses of Buchner Funnel

Vital in the field of organic chemistry, this funnel is chiefly used to collect the recrystallized compounds in the entire process. The vacuum suction dries the wet crystal compounds, such that the dry ones are left behind. Also its use is often combined with sinter seals, Buchner ring and flask. All these components are quite essential during the whole filtration process. The other random uses are listed below:

• In the make of: Glass Bottle
• In liquefied gases for bench-top: Cryogenic Vacuum Flask
• In the phase separation of plants and its constituents: Filtration Plants
• In filter cloths: Industrial Filters
• In economical, cool, long life and tough pumps: Portable Vacuum Pumps
• In distillation and extraction gas units: Sigma Process Plants
• In steam jet ejector vacuum systems: Steam Jet Ejectors

This is perhaps one of the most essential and widely used piece of lab equipment you would find in any chemistry lab. It does help to speed up a chemical process and makes your work much easier. By the way if you are still wondering on the unfamiliarity of this word, it is cited after an industrial chemist Ernst Büchner.