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Q about safety (A/B MHRB mini extraction)

DK_one

Established member
Hey
Had a minor extraction.
Used NAOH for the last time, do not want to have this worries again. But that's me and not the point.

The picture shows the recrystallized end product for now. At the bottom of glass is a slight coloration due to a tabacco crumb that somehow made it in there and I didn't noticed for a few hours. :(

But against my expectation the formations are all over the place instead of grouped. Last time I had two formations with same method.

Anyone here who thinks I need to do any further steps before it is safe to do scientific work with it?
Maybe something to see in picture that I do not know how to spot, like lye hints?
 

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Ok, I do another recrystallize.
With 50°C naphtha over to smaller glass there were residue under formations.
 
assumed that it is unusual

When I felt with my finger the places where these ferns were in the old glass, it felt slippery, perhaps somewhat gel-like. like a film, but no longer visible.
 
Yes, I always got IPA in several sprayer bottle and clean even more then needed. Bit of a money waste even.

Could my problems be rooted in to small plant materials and to much H2O and NPS/DCM

My 2nd reoccurring Problem is, when I evaped or refrigerated there will be mini liquid looking clear spots that take over a week to form to base material.

Good enough English?
 
Edited post:

I'd like to buy a book for understanding more.
Personal don't like to read before a monitor, when it is complex.

I'm looking for a understanding of what is happening and why on Extractions in detail.
Is the book suiting or what topics in a book I should look for?

I'm not sure if the book is maybe to much or way to specific if no pre requirements are met

What you think of this one


I translated the index?


Table of Contents
Preface 1 X
Abbreviations 1 I
1 Bonding Concepts in Organic Chemistry 1
1.1 Hybridization 1
1.2 The Covalent Bond 5
1.2.1 The Single Bond 6
1.2.2 The Double Bond 7
1.2.3 The Triple Bond 9
2 Fundamentals of Organic Chemistry 11
2.1 Spatial Representation 11
2.1.1 The Fischer Projection 13
2.1.2 The Newman Projection 15
2.1.3 The Sawhorse Projection 15
2.1.4 The Haworth Projection 15
2.2 Structure 17
2.2.1 Configuration and Conformation 17
2.2.2 Isomerism 20
2.2.3 Tautomerism 23
2.3 Stability 24 2.3.1 The Carbenium Ion 2 5
2.3.2 The Carbanion 26
2.3.3 The Erlenmeyer Rule 28
2.3.4 Ring Strain 29
2.4 Catalysts in Organic Chemistry 30
2.4.1 Organometallic Catalysts 31
2.4.2 Stoichiometric Additives (Accelerators, Mediators)
3 Aromaticity and Heteroaromaticity 33
3.1 Delocalization, Mesomerism, Aromaticity 33
3.2 Second Substitution on Aromatics 4 2
VI I Table of Contents
3.2.1 Inductive Effect 43
3.2.2 Mesomeric Effect 45
3.3 Annealed Systems 46
3.4 Heteroaromatics 51
3.4.1 Electron-rich heteroaromatics 52
3.4.2 Electron-poor heteroaromatics 55
3.5 Nomenclature 58
3.5.1 Exchange nomenclature 63
4 Reactivity: Polarity of the covalent bond 67
4.1 Electronegativity 67
4.2 Polarity 68
4.2.1 Bond strength 70
4.2.2 Polar moment 71
4.3 Polar bonds in organic chemistry 75
4.3.1 Electrophilic centers 78
4.3.2 Nucleophilic centers 81
4.4 Hydrogen bonding 82
5 Lewis base concept: The importance of Lewis bases in organic chemistry 87
5.1 The definition of Lewis Acids and Lewis Bases 8 7
5.2 The Importance of the Lewis Base as an Electron-Rich Agent 8 9
5.3 The Action of Lewis Acids as Electrophiles 92
5.3.1 The Proton as a Lewis Acid 92
5.3.2 Lewis Acids as Mediators 95
5.4 The Leaving Group 9 7
5.5 The HSAB Concept 200
5.5.1 The Classification into Hard and Soft Acids and Bases 100
5.5.2 The Quantification of the HSAB Concept 101
6 Reaction Mechanisms in Organic Chemistry 105
6.1 Key 105
6.2 Addition 106
6.2.1 Electrophilic Addition 107 6.2.2 Nucleophilic Addition 109
6.2.3 Radical Addition 111
6.2.4 Cycloadditions 113
6.3 Substitution 114
6.3.1 Nucleophilic Substitution 115
6.3.2 Electrophilic Substitution 127
6.3.3 Radical Substitution 136
6.4 Elimination 138
6.4.1 Unimolecular Elimination: The Ei Mechanism 138
6.4.2 Bimolecular Elimination: The E2 Mechanism 139
Table of Contents IV II
6.4.3 The EjcB Mechanism of β-Elimination 140
6.4.4 Intramolecular Elimination: The E or Syn Mechanism 141
6.5 Condensation 142
6.6 Rearrangements 143
6.6.1 Pinacolum Rearrangement 143
6.6.2 Beckmann Rearrangement 143
6.6.3 Claisen Rearrangement 145
7 Functional Groups and Their Derived Reactivities 147
7.1 The Hydrocarbons 148
7.1.1 The Alkanes 148
7.1.2 The Alkenes 151
7.1.3 The Alkynes 159
7.1.4 Aromatics 160
7.1.4.1 Second Substitution 163
7.2 Halogen Compounds 168
7.3 Alcohols (Mercaptans) 174
7.4 Amines 180
7.5 Etilers (Thioethers) 187
7.6 Carbonyl Compounds 192
7.6.1 Aldehydes 193
7.6.2 Ketones 201
7.6.3 Imines 203
7.6.4 Carboxylic Acids 204
7.6.5 Carboxylic Anhydrides 208
7.6.6 Carboxylic Halides 210
7.6.7 Esters 212
7.6.8 Carboxylic Amides 213
7.7 Nitriles 215
A Overview Diagrams 219
B Glossary 221
C Correctly Solved 243
Index 263
 
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The book will get you a solid grounding in the theory of organic chemistry, although that won't necessarily help you to understand all the practical aspects of extraction. You'd want something along the lines of, say, Harwood and Moody's "Experimental Organic Chemistry", or a more up to date equivalent - or its equivalent in (presumably) German for you. You could try finding out what the recommended practical organic chemistry texts are for universities in German-speaking countries. This is something I'm yet to look into.
 
Ok big thanks on that.
I found some lines online of that book I found. But honestly it was like exactly putting a million questions up in six lines....
Interesting for sure, but I think I will try to nail something out of your suggestion for my own. If that makes sense....
 
Ok that's what's left in the Glas recrystallized pic 1 (3.8 mb)

The bowl shows a bad extraction with similar issue...

But I am currently at a new pull
 

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No maybe they are to big?
not sure why they behave this way 😕
Ah, and yeah didn't knew of that mb for millibar.

Btw, I consider this extraction as a fail and made notes to prevent possible failures.
The actual Stb looks pretty good so far. First time the nps did change in color on all 3 pulls in every glass.
And I didn't trash the 'lye soup's yet and won't before I am sure I should. :)


Is it correct to pull with NPS until the color no longer changes? Or could the color change occur in another way? For example, the new NPS is equipped with C1-C14 instead of just C6-8 if I remember correctly.
 
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Ok ty.

I just came across a seoeratory funnel statement and emulsion which are hard to dissolve.

This book mentioned to rotate slightly with the cap removed then put funnel to stative. When sitting in Stativ put on cap again and shortly open the valve.
By doing this the water later at bottom gets a pressure weight which helps dissolve the emulsion.

What you think of this or got XP with it maybe?
Sounds interesting to me....
 
Ok ty.

I just came across a seoeratory funnel statement and emulsion which are hard to dissolve.

This book mentioned to rotate slightly with the cap removed then put funnel to stative. When sitting in Stativ put on cap again and shortly open the valve.
By doing this the water later at bottom gets a pressure weight which helps dissolve the emulsion.

What you think of this or got XP with it maybe?
Sounds interesting to me....
"stative/Stativ" = "stand" (noun)

The mild underpressure might help with some types of emulsion. It's certainly another simple thing to try before resorting to more complicated or drastic measures. Bear in mind, this is simply building up a repetoire of techniques and no one of them is the magic solution to the problem, even if some will be far more likely to work than others. It's only experiece that will help you to judge which trade-off between ease of execution and likelihood of success will be your best entry point - and understanding exactly how the emulsion occurred will inform you further down the line for a more effective approach, namely prevention.
 
Ok, just read it and didn't come across in the forum yet, but it can be worth the try.
I am trying or I am taking notes and stuff as seriously as I can and lately I am getting to a point I would consider myself not a total newb anymore! And I wasn't looking for magic just for another worth to try thingy....

Oh and it was said I think that this method is recommended for when the 2 phases are to close in there balance?! Any sense in this sentence? I'd assume for example using DCM on a very high loaded NAOH phase?
 
Oh and it was said I think that this method is recommended for when the 2 phases are to close in there balance?! Any sense in this sentence? I'd assume for example using DCM on a very high loaded NAOH phase?
That seems to make sense, although the DCM may or may not be the bottom layer in that situation. "Close in their balance" is somewhat ambiguous without providing the full context.
 
Ya ok sure didn't though about the realistic scenario of my example.

Or was it about density? Maybe I will give you the book example with a screenshot later
 
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