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#26 2018-04-17 09:18:21

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,748
Website

Re: Sagan City - what will be there?

Soap can be made from vegetable oil treated with either sodium hydroxide or potassium hydroxide. This is the chemically pure form of lye. Traditional method of production was to percolate water through wood ash, but modern method is electrolysis of salt. To be more precise, it's electrolysis of brine: salt dissolved in water. This produces hydrogen gas on one electrode, chlorine gas on the other. The two gasses can be placed in a chamber with no oxygen, just the two gasses, and burned. This will produce hydrogen chloride; when that's dissolved in water it's called hydrochloric acid. Sodium hydroxide dissolved in water is called caustic soda, a very strong alakali. Both hydrochloric acid and caustic soda are important chemicals for many industrial processes. One use is to process aluminum ore. Soap made of vegetable oil and lye is compatible with septic tanks, it just adds organic matter.
600px-Chloralkali_membrane.svg.png

Different vegetable oils produce different properties of soap. I tried create a recipe that didn't involve any animal products, and didn't use any tree oil. The reason is trees are large and grow slowly. My efforts were not successful, the soap was more of a thick paste. One alternative is to not even try to make it solid, just make liquid soap. That can be made with potassium hydroxide instead.

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#27 2018-04-17 12:25:46

Palomar7
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From: USA
Registered: 2017-12-20
Posts: 81

Re: Sagan City - what will be there?

Oh, I *like* Sagan City. :-)

Hopefully it will be.


Original registration - May 2002

I want that Million Year Picnic on Mars

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#28 2018-04-17 12:56:17

Oldfart1939
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Registered: 2016-11-26
Posts: 1,646

Re: Sagan City - what will be there?

Solid soaps require significant quantities of either Palmitic acid and Stearic acid as the fatty acid components in the starting triglyceride. Both are found in animal fats, along with smaller quantities of Lauric acid, the C-12 member of the homologous series. Polyunsaturated fats, such as those found in vegetable oils, make "soft soaps." The other significant product of saponification, as "soap making" is called in the laboratory. Those wishing to try their luck can buy some lard as the starting material.

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#29 2018-04-17 17:21:48

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,704

Re: Sagan City - what will be there?

I see from this site that cocoa is a very good source of stearic acid.

https://wholefoodcatalog.info/nutrient/ … ds/high/2/

Isn't the lesson of the Impossible Burger that we can normally find v. good substitutes for animal products in the non-animal world?  And even if we can't do that we can recreate the chemicals in the lab...

Oldfart1939 wrote:

Solid soaps require significant quantities of either Palmitic acid and Stearic acid as the fatty acid components in the starting triglyceride. Both are found in animal fats, along with smaller quantities of Lauric acid, the C-12 member of the homologous series. Polyunsaturated fats, such as those found in vegetable oils, make "soft soaps." The other significant product of saponification, as "soap making" is called in the laboratory. Those wishing to try their luck can buy some lard as the starting material.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#30 2018-04-17 17:54:01

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,748
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Re: Sagan City - what will be there?

Miller's Homemade Soap Pages: All-Vegetable Soaps Page

Excel spreadsheet template (vegetable oils & animal oils/fats): soapsheet3.xlt

Trying to find a table of fatty acids in various oils and fats. I had it years ago; where is it? Anyway, making soap with animal fat (such as lard) requires heating it to melt the fat. Working with hot fat can be dangerous. It's safer to start with oil that's liquid at room temperature. Soap making does require pouring lye into oil to create a chemical reaction. For it to work, the lye must be strong enough for the reaction. Doing that with hot melted fat could be dangerous, you don't want to splash any onto yourself. At least that's what I read as a caution for a beginner.

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#31 2018-04-17 22:10:10

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,646

Re: Sagan City - what will be there?

I guess I tend to overlook the hazards involved, as this is quite an easy process for a trained chemist to accomplish. If I were coaching someone to do the soap making I would insist on proper personal protective equipment consisting of goggles for eye protection and rubber gloves in addition to a plastic or rubber apron. My old German relatives on the farm in Illinois were said to make their soap in big cast iron kettles immediately after rendering the lard from slaughtered hogs.

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#32 2018-04-18 03:21:05

elderflower
Member
Registered: 2016-06-19
Posts: 1,096

Re: Sagan City - what will be there?

Soap as made by reaction of triglycerides (oils and fats) with caustic will contain the byproduct glycerine. The result is known as soft soap. You can't make cakes of it until you remove the glycerine, but it still works for washing people or materials.

Last edited by elderflower (2018-04-18 03:21:47)

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#33 2018-04-18 11:21:06

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,748
Website

Re: Sagan City - what will be there?

elderflower wrote:

Soap as made by reaction of triglycerides (oils and fats) with caustic will contain the byproduct glycerine. The result is known as soft soap. You can't make cakes of it until you remove the glycerine, but it still works for washing people or materials.

glycerin soap
220px-Pears-Soap-barbox.jpg

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#34 2018-04-20 11:14:43

elderflower
Member
Registered: 2016-06-19
Posts: 1,096

Re: Sagan City - what will be there?

They leave some of it in, but not all.

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#35 2018-04-20 12:29:12

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,748
Website

Re: Sagan City - what will be there?

elderflower wrote:

They leave some of it in, but not all.

Read the linked web page for Miller's Homemade Soap. It describes in detail how to make soap.

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#36 2018-04-20 12:34:10

kbd512
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Registered: 2015-01-02
Posts: 2,883

Re: Sagan City - what will be there?

Rob,

Thanks for the link.  My daughter will undoubtedly want to try some of those recipes.

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#37 2018-04-20 14:07:58

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,565
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Re: Sagan City - what will be there?

About 5 decades ago,  all of us in my high school chemistry class made soap out of something and lye in the lab. 

This was a regularly-scheduled lab supervised by the teacher.  Somehow or another,  the stuff we made could be squeezed together into a bar.  Nobody got hurt,  and we actually used the soap to wash our hands. It worked at least as good as anything else available at that time. 

Same class:  we also made aspirin.  But the teacher very pointedly told us not to take it.  It was impure,  and would give you a headache.  Not relieve one. 

We also built stills,  blew up sodium in water,  and a whole lot of other fun stuff. 

All in all,  I cannot say education has improved since then.  You learn by doing,  and today you are not allowed to do those things by the nanny state.

Back then,  nobody sued anybody if little Bobby burnt or cut his finger in chemistry or physics or biology lab.  They just told little Bobby not to be so stupid next time. 

As late as 1997,  I taught college labs where we made real stuff. One was a Reid vapor pressure lab exercise.  It required heating closed containers on a stovetop containing gasoline under air.  That's literally how you do the Reid vapor pressure test,  there is no other way.  I had to watch like a hawk because of gasoline and electricity,  but NO ONE ever got hurt in my lab. 

Another was composite materials.  It was hard to get it through their heads that epoxy systems are usually near 1:1 resin: hardener,  while polyester and vinyl ester systems are resin plus only a trace catalyst.  Lots of 1:1 over-catalyzed mix cup fires,  and lots of epoxy projects that no oven could ever cure,  but NO ONE ever got hurt in my labs. 

You just watch 'em closely.  With a fire extinguisher and a first aid kit handy. Simple as that.

GW

Last edited by GW Johnson (2018-04-20 14:14:37)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#38 2018-04-20 14:32:44

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,646

Re: Sagan City - what will be there?

BITD, soap making was a favorite Science Fair project. I have no idea about how kids learn anything of value in so-called laboratories monitored by the Nanny State. Learn by doing? Thing of the past.

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#39 2018-04-20 18:12:50

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,704

Re: Sagan City - what will be there?

I expect there to be an observation tower in Sagan City.  Not very tall, but maybe 100 feet high, to give some views over the surrounding landscape.

Other features of the early Sagan City:

1. A sculpture park - part pressurised environment, part outside.

2.  Outside areas will be "humanised" through brick paving, sculptures, artificial trees and bushes, and nocturnal lighting.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#40 2018-04-20 19:02:18

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 15,806

Re: Sagan City - what will be there?

Still had bunsen burners in the science class room but as for doing stuff in class as a high schooler we did not do anything with the equipment. No experiments with chemicals at all so if I wanted to learn about science we would buy our own chemistry kit.
In fact all shop trade school classes that would be in high school are all gone and are farmed out if you want to travel to another school losing out on your schools other classes in order to be in the trades.

Back to Sagan city which is long after the hard stuff has been done with getting a toehold on mars. Such things as the making of soap is part of the foothold to gaining independance from earths supply train. Its up to the hearty worker man that will not be given a chance as its out of there price range and the rich are going for the joy ride.

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#41 2018-04-20 20:21:45

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,748
Website

Re: Sagan City - what will be there?

I am reminded of the movie "Fight club". Part of the premise was the main character stole bags of human fat from the dumpster outside a liposuction clinic. He converted that human fat into soap. He marketed his soap as the best soap for your skin.
MV5BMzFjMWNhYzQtYTIxNC00ZWQ1LThiOTItNWQyZmMxNDYyMjA5XkEyXkFqcGdeQXVyNzkwMjQ5NzM@._V1_UX182_CR0,0,182,268_AL_.jpg

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