[gwking]

I have never seen the word “partition” used in this way before. Hard to search for examples because unrelated computer graphics articles about surface partitioning dominate. I did find this:

Partitioning is the distribution of a solute, S, between two immiscible solvents (such as aqueous and organic phases). It is an equilibrium condition that is described by the following equation:

S(aq) ⇄ S(org)

Interesting to think that a surface can play a role comparable to a solvent. I wonder what a chemist would have to say about it.

https://www.chemicool.com/definition/partitioning.html

[s0rce]

I'm a materials scientist/chemist and the word partition made sense in this context. The VOC/solute is preferentially on surfaces vs floating in the air. This finding doesn't seem super surprising to me given the large surface area of all the stuff in a home.

[PaulHoule]

See https://en.wikipedia.org/wiki/Octanol-water_partition_coeffi... and https://en.wikipedia.org/wiki/Adsorption

[pbhjpbhj]

In the UK a non-structural wall is called a partition wall -- they're usually plasterboard (I think that is called sheetrock in USA) over wooden studs whilst ordinarily walls are plaster on brick/stone.

I wonder which partitions more VOCs/SOCs, partition or structural walls.

[PaulHoule]

More generally partition (as a verb) means "to divide into parts" which is used for numerous purposes such as

-- to divide a country into parts (e.g. separate Pakistan and Bangladesh from India)

-- to divide a physical space with walls

-- to divide a population of molecules between molecules floating in the air and molecules stuck on walls

[tsimionescu]

Also to separate a computer network into two or more disconnected networks, the P in the CAP theorem stands for "partition tolerance" (i.e. that a system can keep working in case its components end up in a partitioned network).

[whatevertrevor]

-- "Divide" an integer into two or more integers that sum to it too. :D

[JadeNB]

The trivial partition n = n also usually counts as a partition. This is useful if you want to be able to dualize partitions, and want n = 1 + 1 + ... + 1 to have a dual partition.

[lazide]

Also to divide digital storage into individually addressable segments (disk partitions).

[Polizeiposaune]

A more generic term is drywall or gypsum board. It generally is covered by a skim coat of plaster and is then painted.

"Sheetrock" is a particular brand of drywall. For instance, see https://www.lowes.com/pl/drywall/sheetrock-brand/4294864808-...

[ninalanyon]

Gypsum board is a considerably more specific, less generic, term than partition. My wooden house has some internal non-structural walls but none of them use gypsum boards (called plasterboard in British English).

Neither are they skimmed with plaster. They are instead faced with a very dense and flat hardboard.

[quickthrowman]

Gypsum board is the term for a type of wall covering, which itself is part of a partition.

A partition is an interior wall assembly typically consisting of framing, (optional) insulation, and a wall covering (like gypsum board, but this could be anything: wood, shiplap, masonry, lath and plaster, etc.)

[ChoGGi]

You only tape the joints, not the whole wall.

[quickthrowman]

There are multiple levels of drywall finishing. A level 5 (highest grade) finish involves skim coating the entire gypsum wallboard with joint compound.

It’s not very common, but it is used in some commercial settings.

[hxorr]

I think it would depend on what paint is used. Although I would strongly suspect exposed porous surfaces like plaster, masonry, drywall to have a large reservoir capacity due to their surface area at the microscopic level

[fuzzfactor]

In separation science a partitioning coefficient can be described for an undesirable contaminant, inbetween a solid adsorbent having a certain degree of retention, versus a solvent where it is soluble to its own certain degree, under static equilibrium conditions.

IOW the smoke will have different affinity for different types of furniture, carpets, and window coverings, and when it comes in contact with these they soak it up like a sponge. Because the adsorbent materials are physically like a sponge more often than not, whether on a macro, micro, or molecular level.

The solvent is plain air, but the "solubility" of the raw smoke in air is not a factor because the smoke is not actually dissolved in the solvent (air) at this point, or ever really. The smoke consists of a lot of solid particles that have been forcefully dispersed into the air at uneven concentrations. The smoke itself is not a chemical contaminant that dissolves in the air, it's just dispersed in the air not much differently than an unwanted chemical, for a least a good period of time.

But the solids will eventually settle if they are not purged beforehand. What you're left with after that is then chemical equilibrium.

In a confined enclosure, static equilibrium will eventually be reached between the amount of chemical contaminants dissolved in the air at that temperature, versus the amount adsorbed onto available surfaces. After which no more odor can be released from the furniture once the air is saturated. To really get rid of the smell you're going to have to replace the saturated air with fresh air and one compete air exchange is not usually enough. Also the more efficient air exchange the better, and the fresher the better. If one person smoked one time, or you burned some popcorn and did not let out the smoke right away, that's not much contamination and it's not constant, but it's also not unusual to still smell it a week later when you first walk in from a fresh outdoor air environment. But just don't open the windows when something like a diesel truck is idling outside, new odor could then be coming in in greater quantities than the old odor can escape, one roomful at a time.

You may have grams of "odor" soaked into the carpet along with 100 grams of dirt & dust. But what if the chemical causing the odor only "evaporates" into the air a few milligrams at a time? Because the heavier the liquid, the slower the evaporation and the resulting partitioning coefficient using air as a solvent is such a low number. And it's not too unintuitive to figure that things which are semi-solid like tars or true solids like some pesticides hardly evaporate at all, but can really stink when there's only a few milligrams in the air.

Stuff like that is not going away without a solvent much stronger than air, and also a more concentrated solvent than a gaseous fluid can make contact by the gram much faster than a gram of fresh air can eventually flow by the unwanted material to be removed.

Plain water may not be any better as a solvent at dissolving cooking oils and tars than air is a solvent, but you sure can get a lot more grams into contact with a surface or macro adsorbent quicker compared to air as a gas.

Plain steam dissolves things so much better just from the added heat of the liquid turning it into a stronger solvent, plus so much of the water evaporates so fast at that temperature there is also a purging effect.

Then there's the carpet-cleaning liquids that can improve the partitioning coefficient of water so it will dissolve otherwise insoluble materials without nearly as much heat as steam. Like grams of detergent added to volumes of water to clean a certain area of carpet, or hundreds of grams of water-soluble organic solvent over the same area instead. Or both, simultaneously, or sequentially. Then when you do the math you see how much more effective sequentially is.

Now without doing any carpet cleaning, when you enhance the air exchange rate to do as good a job removing odors as that can accomplish, you are then trying to establish a dynamic equilibrium so odors are being purged outward at an enhanced rate due to increased fresh solvent (air) flow. Kind of like sequential carpet cleaning. One window fan blowing in and one blowing out at opposite ends of the structure can sometimes be more effective than all windows open whether or not using the same fans.

>I wonder what a chemist would have to say about it.

I wouldn't be surprised if people are still wondering :)

Edit: Hopefully they're wondering even more about a lot of things where they didn't know there were equations, actually ;)