ugly-but-optimistic
Bronze
- Joined
- Jun 14, 2021
- Posts
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most salicylic acid products are very watered down (2%) and next to useless
here's a simple procedure i use to make it in almost pure form!
but for heaven's sake wear gloves when using acids and alkalis
i use 30% (mixed with moisturiser) on my face once a month
it makes a very effective chemical peel
ingredients:
feedstock (methyl salicylate)
58 g 50 mL
sodium hydroxide
39 g 18 mL
water (for NaOH)
193 g 193 mL
sulphuric acid
116 g 63 mL
water (for H2SO4 3M)
317 mL
total volume (at freezing step) theoretical yield
642 mL 53 g
method :
* reflux the methyl salicylate and NaOH solution for 20 - 30 mins
* acidify the mixture with H2SO4 solution, add slowly with lots of stirring
* place in freezer
* filter the crystals and discard the supernatant
actual :
* 45 minutes boiling
* added 150mL water every 10 minutes (no reflux)
* no MS smell, just plain steam, due to boiling points
* left for 15 minutes after heat turned off
* resulting solution was light brown yellow, like urine
* added 200mL water
* slowly added 100mL HCl with a lot of stirring, solids formed quickly as pH passed critical point
* filtered through linen, filter cake was light yellow in colour, supernatant was dark orange
* 200mL vinegar added as wash (could have used water but wanted to ensure low pH)
* washed again twice with chilled water (don't use room temp water as the product will dissolve)
* dried in the sun
references :
www.healthline.com
www.healthline.com
en.wikipedia.org
here's a simple procedure i use to make it in almost pure form!
but for heaven's sake wear gloves when using acids and alkalis
i use 30% (mixed with moisturiser) on my face once a month
it makes a very effective chemical peel
ingredients:
feedstock (methyl salicylate)
58 g 50 mL
sodium hydroxide
39 g 18 mL
water (for NaOH)
193 g 193 mL
sulphuric acid
116 g 63 mL
water (for H2SO4 3M)
317 mL
total volume (at freezing step) theoretical yield
642 mL 53 g
method :
* reflux the methyl salicylate and NaOH solution for 20 - 30 mins
* acidify the mixture with H2SO4 solution, add slowly with lots of stirring
* place in freezer
* filter the crystals and discard the supernatant
actual :
* 45 minutes boiling
* added 150mL water every 10 minutes (no reflux)
* no MS smell, just plain steam, due to boiling points
* left for 15 minutes after heat turned off
* resulting solution was light brown yellow, like urine
* added 200mL water
* slowly added 100mL HCl with a lot of stirring, solids formed quickly as pH passed critical point
* filtered through linen, filter cake was light yellow in colour, supernatant was dark orange
* 200mL vinegar added as wash (could have used water but wanted to ensure low pH)
* washed again twice with chilled water (don't use room temp water as the product will dissolve)
* dried in the sun
references :
Salicylic Acid for Acne: Benefits, Dosages, and Side Effects
Salicylic acid is widely available and used regularly for reducing acne. Learn about its benefits, proper dosages, use when pregnant, and potential side effects.
www.healthline.com
Which Is Better for Acne, Salicylic Acid or Benzoyl Peroxide?
Salicylic acid and benzoyl peroxide are arguably two of the most well-known acne fighters. But which one should you use and when?
www.healthline.com
