LECTURE № 3
Inorganic drugs with acid-base
properties. Inorganic official compounds
of Carbon, Aluminium, Barium, Silver,
which are used in the medical practice
Associate prof. Mosula L.M.
The plan
1. Inorganic acids as drugs: Hydrochloric acid, Boric acid.
2. Borax - pharmacopoeial preparation of sodium salt of boric
acid.
3. Pharmacopoeial preparations of Ammonia: Strong ammonia
solution, Dilute ammonia solution.
4. Sodium Bicarbonate.
5. Inorganic drugs of Carbon: Activated Charcoal , Sodium
bicarbonate.
6. Inorganic drug of Aluminium: Dried Aluminium hydroxide.
7. Inorganic drug of Barium: Barium sulphate.
8. Inorganic drug of Silver: Silver nitrate.
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Hydrochloric Acid
Hydrochloric Acid
General Notices
(Concentrated Hydrochloric Acid, Ph Eur monograph 0002)
Acidum hydrochloriсum
Аcidum muriaticum
HCl
36.46 7647-01-0
DEFINITION
Content
35.0 per cent m/m to 39.0 per cent m/m.
35.0 per cent m/m to 39.0 per cent m/m.
OBTAINING
General industrial method for obtaining hydrogen chloride is synthesis from
gases hydrogen H2 and chlorine Cl2. This gases is obtained by electrolysis
water solution of sodium chloride: (in the solution is ions of Na+ and Cl–, and
dipoles of water Н2О):
Cathode (–): Na+; Н2О
2Н2О + 2е  2ОН– + Н2 (reduction)
Anode (+): Cl– ; Н2О
2Cl– – 2e  Cl2
(oxidution)
General reaction:
2NaCl + 2HOH H2 + Cl2 + 2NaOH
cathode anode
Obtained gases to burn in the contact furnace:
Н2 + Сl2 = 2НCl
Obtained gas (HCl) to pass through absorption tower with water - hydrogen
chloride (HCl –gas) freely soluble in water, and formed Hydrochloric acid with
concentration 35–37 %, it is fuming hydrochloric acid. Saturated at t =18 С
solution of Hydrochloric acid has 42 % gas hydrogen chloride.
CHARACTERS
Appearance
Clear, colourless, fuming liquid.
Solubility
Miscible with water.
Relative density
About 1.18.
IDENTIFICATION
A. (BrPh, SPU, add. 1). Dilute with water R. The solution is strongly acid (2.2.4).
Tabl. Relationship between reaction of solution, Approximate ph and colour of
certain.
B. (BrPh, SPU, add. 1). It gives the reactions of chlorides (2.3.1).
HCl + AgNO3 → AgCl↓ + НNO3;
Cl– + Ag+ → AgCl↓
AgCl↓ + 2NH4OH → [Ag(NH3)2]Cl + 2H2O.
B. (BrPh, SPU). Reaction with potassium dichromate in the sulphuric -acid
medium.
Э14HCl + K2Cr2O7 = 3Cl2 + 2CrCl3 + 2KCl + 7H2O
Cr2O72– + 14H+ + 6е  2Cr3+ + 7Н2О
2Cl– – 2е  Cl2
NH
O
C
NH
diphenylcarbazide
(colourless)
NH
NH
C 6H5 + CL
2
C 6H5 -2 HCl
N
O
N
C 6H5
+ CL2
C
NH
NH
C 6H5 -2 HCl
diphenylcarbazone
O
N
N
C 6H5
N
N
C 6H5
C
diphenylcarbadiazone
(orange-yellow)
C. (BrPh, SPU, add. 1). It complies with the limits of the assay.
(violet-red)
ASSAY
(BrPh, SPU, add. 1). Alkalimetry, direct titration
HCl + NaOH = NaCl + H2O
Еm(HCl) = M. m.
STORAGE
In a stoppered container made of glass or another inert material, at a
temperature not
exceeding 30 °C.
Preparation
Dilute Hydrochloric Acid
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Dilute Hydrochloric Acid
Dilute Hydrochloric Acid
General Notices
(Ph Eur monograph 0003)
Acidum hydrochloricum dilutum
Ph Eur
HCl
SPU, add 1
DEFINITION
Content
9.5 per cent m/m to 10.5 per cent m/m of HCl (Mr 36.46).
PREPARATION
To 726 g of water R add 274 g of concentrated hydrochloric acid and mix.
IDENTIFICATION the same as Concentrated Hydrochloric Acid.
ASSAY
Alkalimetry, direct titration
Action and use
Agent, which regulated metabolic processes. 0,3–0,5 % HCl use at
insufficient gastric acidity.
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Boric Acid
SPU
Boric Acid
General Notices
(Ph Eur monograph 0001)
Acidum boricum
H3BO3
61.8ээ10043-35-3
Ph Eur
DEFINITION
Content
99.0 per cent to 100.5 per cent.
OBTAINING
Interaction hot hydrochloric acid (or sulphuric acid) with tetraborates (borax
Na2B4O710H2O or boron-calcite СаB4O74H2O) (for medicinal purposes):
Na2B4O710H2O + 2HCl = 4Н3ВО3 + 2NaCl + 5H2O
СаB4O74H2O + 2HCl + Н2О = 4Н3ВО3 + СаCl2
Na2B4O7 + H2SO4 + 5H2O = 4Н3ВО3 + Na2SO4
CHARACTERS
Appearance
White or almost white, crystalline powder, colourless, shiny plates greasy to the
touch, or white or almost white crystals.
Solubility
Soluble in water and in ethanol (96 per cent), freely soluble in boiling water and in
glycerol (85 per cent).
IDENTIFICATION
эA. (BrPh, SPU). Bromomethyl ester formation. Dissolve 0.1 g by gently heating in 5
ml of methanol R, add 0.1 ml of sulphuric acid R and ignite the solution. The flame has a
green border.
Н3ВО3 + 3СН3ОН  (СН3О)3В + 3Н2О
B. (BrPh, SPU). Interaction with indicators. Solution S (see Tests) is acid (2.2.4).
ASSAY
(BrPh, SPU). Alkalimetry, direct titration. Dissolve 1.000 g with heating in 100 ml of
water R containing 15 g of mannitol R. Titrate with 1 M sodium hydroxide, using 0.5 ml of
phenolphthalein solution R as indicator, until a pink colour is obtained.
1 ml of 1 M sodium hydroxide is equivalent to 61.8 mg of H3BO3.
NaOH + Н3ВО3 = NaВО2 + 2H2O
NaВО2 + 2H2O = Н3ВО3 + NaOH.
If titrate only with 1 M sodium hydroxide without mannitol R then the medium becomes alkaline before end
point that is drug substance is titrated not completely.
For intensification of acid properties of boric acid add polyatomic alcohol - mannitol (hexatomic alcohol, it
formatted with boric acid complex compound. Then the complex
compound titrate with 1 M sodium
hydroxide:
_
_
CH2OH
HO
H
HO
H
H3BO3 + 2
CH2OH
- 3H2O
+
HO
H
H
OH
HO
H
H
OH
H
H
OH
H
OH
H
OH
H
O
CH2OH
CH2OH
HO
H
O
H
CH2OH
NaOH
Na
+
HO
H
H
OH
HO
H
H
OH
+ H2O.
H
OH
H
O
B
CH2O
CH2O
HO
H
O
H
B
Em (Н3ВО3) = М.m.
Action and use.
CH2OH
CH2O
Antiseptic agent.
CH2O
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Borax
SPU
Borax
General Notices
Sodium Borate; Sodium Tetraborate
(Ph Eur monograph 0013)
Natrii tetraboras
Natrium tetraboriсum
Na2B4O7,10H2Oэ
э381.4ээ1303-96-4
Ph Eur
DEFINITION
Disodium tetraborate decahydrate.
Content
99.0 per cent to 103.0 per cent of Na2B4O7,10H2O.
CHARACTERS
Appearance
White or almost white, crystalline powder, colourless crystals or crystalline
masses,
efflorescent.
Solubility
Soluble in water, very soluble in boiling water, freely soluble in glycerol.
IDENTIFICATION
A. (BrPh, SPU). Bromomethyl ester formation.
B. (BrPh, SPU). Action the water solution of borax on indicators. To 5 ml of solution
S add 0.1 ml of phenolphthalein solution R. The solution is red. On the addition of 5 ml of
glycerol (85 per cent) R the colour disappears.
Water solution of borax owing to hydrolysis has the alkaline reaction (pН 7):
Na2B4O7 + 7HOH = 2NaOH + 4H3BO3
pН = 9,0 - 9,6
At addition glycerol to water solution of borax there is formation boron-glyceric acid and the
CH2OH has acid reaction of medium (colouring
HOCH2
CH2OH of phenolphthalein
solution
solution disappears):
HO
+
2 CHOH
+
HO
CH2OH
H
B OH
HC
O
H2C
O
+
O CH
B
3 H2O
O CH2
C. (BrPh, SPU). Solution S gives the reactions of sodium (2.3.1).
H2C OH
H2C OH
HO CH
HO CH
+
Na2B4O7
8 HC OH 1 м ол ь
2
HO CH
HC OH
HO CH
HC OH H
+
HC OH
HC OH
HC O
H2C OH
H2C O
H2C OH
+
2 H
HO CH
B
HO CH
HC OH
HC OH Na
HC OH
HC O
O CH2
H2C O
HO CH
HC OH
HC OH
HO CH
B
+
+
2 NaOH
2 mol
+ 7H2O
HO CH
B
O CH
O CH2
H2C OH
HO CH2
HC OH
H2C O
+2
HO CH2
HO CH
O CH
HO CH
HC O
H2C OH
HO CH2
HO CH2
HO CH
HC OH
+ HO CH
HC OH
2 Na
HC OH
O CH
HC O
O CH2
H2C O
HO CH
B
O CH
O CH2
+
2 H2O
ASSAY
(BrPh, SPU). Alkalimetry mannitol solution of borax.
H2C OH
+
2 H
HO CH
HC OH
HO CH
HC OH
HC OH
HC O
HO CH
B
H2C O
2 NaOH
+
Na2B4O7
HC OH 1 m o l
2
HC OH
+ HO CH
HC OH
2 Na
HC OH
O CH
HC O
O CH2
H2C O
HO CH
HC OH
HC O
H2C OH
H2C O
+
HC OH H
HC OH
HO CH
B
HO CH
B
+2
+
2 H2O
O CH
O CH2
H2C OH
HO CH2
HC OH
HO CH2
HO CH
2 mol
HO CH
HO CH
8
+
H2C OH
H2C OH
HO CH
H2C OH
HO CH2
HO CH2
HO CH
HC OH
HO CH
HC OH Na
HC OH
O CH
HC O
O CH2
H2C O
HO CH
B
Em(Na2B4O7∙ 10H2O) = M.m./2
O CH
STORAGE. Protected from air.
Action and use.
Antiseptic agent.
O CH2
+
+ 7H2O
?
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Dried Aluminium Hydroxide
General Notices
Dried Aluminium Hydroxide
(Hydrated Aluminium Oxide, Ph Eur monograph 0311)
Aluminii hydroxydum
Al(OH)3
Algeldratum*
Argilla pura
Aluminium hydroxydatum
DEFINITION
Content
47.0 per cent to 60.0 per cent of Al2O3 (Mr 102.0).
CHARACTERS
Appearance
White or almost white, amorphous powder.
Solubility
Practically insoluble in water. It dissolves in dilute mineral acids and in solutions
of alkali
hydroxides.
IDENTIFICATION
(BrPh, SPU). Solution S (see Tests) gives the reaction of aluminium (2.3.1).
Aluminium Salts
Dissolve about 15 mg of the substance to be examined in 2 ml of water R or
use 2 ml of the prescribed solution. Add about 0.5 ml of dilute hydrochloric acid R and
about 0.5 ml of thioacetamide reagent R. No precipitate is formed. Add dropwise
dilute sodium hydroxide solution R. A gelatinous white precipitate is formed
which dissolves on further addition of dilute sodium hydroxide solution R. Gradually
add ammonium chloride solution R. The gelatinous white precipitate is reformed.
Al(OH)3 + 3HCl = AlCl3 + 3H2O
solution
AlCl3 + 3NaOH = Al(OH)3 + 3NaCl
gelatinous
white precipitate
Al(OH)3 + 3NaOH = Na3[Al(OH)6]
precipitate dissolves
Na3[Al(OH)6] + 3NH4Cl = Al(OH)3 + 3NaCl + 3NH4OH
gelatinous
white precipitate is re-formed
ASSAY
(BrPh). Chelatometry, back titration.
Other method – Gravimetry.
Shot of test substance of Al(OH)3 dry, fry to constant mass and lower (weight or
gravimetric form – Al2O3):
2Al(OH)3 Al2O3 + 3Н2О
Calculate content clear Al(OH)3 in the preparation by formula:
m(Al 2 O 3, )there
F
% 
m(Al(OH ) 3 )
100 %
F – gravimetric factor, calculate by formula:
F
2M ( Al (OH ) 3
.
M ( Al 2O3)
STORAGE
In an airtight container , at a temperature not exceeding 30 °C.
Action and use
Antacid.
Preparations
Aluminium Hydroxide Tablets
Co-magaldrox Oral Suspension
Co-magaldrox Tablets
Compound Magnesium Trisilicate Tablets
Ph Eur
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Barium Sulphate
SPU, add. 1
Barium Sulphate
General Notices
(Ph Eur monograph 0010)
Barii sulfas
Barii sulfas pro roentgeno
Barium sulfuricum pro roentgeno
BaSO4
ээ233.4ээ7727-43-7
OBTAINING
1. From nature mineral barite ВаSО4
Stages:
а) Barite ВаSО4 reduction by coal С at fry to barium sulphide ВаS:
BaSO4 + 2С = ВаS + 2CO2
б) Processing by hydrochloric acid HCl; soluble salt of barium chloride BaCl2 is
formed:
BaS + 2HCl = H2S + BaCl2
в) Precipitation of BaSO4 by sodium sulphate Na2SO4, or magnesium sulphate
MgSO4 or sulphatic acid H2SO4:
BaCl2 + Na2SO4  BaSO4 + 2NaCl
That BaSO4 will be superfine, solutions must be very dilute, and beside, add protective
colloid (linseed or linseed mucilage) for slowly precipitation of BaSO4.
Precipitate of BaSO4 screen wash by water (for inadmissible impurities of Chlorides:
soluble salt BaCl2 is toxic). Thus wash off and impurities of Sulphates SO42–.
CHARACTERS
Appearance
Fine, white or almost white powder, free from gritty particles.
Solubility
Practically insoluble in water and in organic solvents. It is very slightly soluble
in acids and in
solutions of alkali hydroxides.
IDENTIFICATION
эA. (BrPh, SPU, add. 1). Boil a suspension of 0.2 g with 5 ml of a 500 g/l
solution of sodium carbonate R for 5 min, add 10 ml of water R, filter and
acidify a part of the filtrate with dilute hydrochloric acid R. The solution gives
the reactions of sulphates (2.3.1).
BaSO4 + Na2CO3
BaCO3  + Na2SO4
carbonization
white
precipitate on the filter
Sulphates
A. (BrPh, SPU). Reaction with barium chloride solution in the hydrochloricacid medium. Dissolve about 45 mg of the substance to be examined in 5 ml of
water R or use 5 ml of the prescribed solution. Add 1 ml of dilute hydrochloric
acid R and 1 ml of barium chloride solution R1. A white precipitate is formed.
Na2CO3 + 2HCl = NaCl + H2O + CO2
Na2SO4 + BaCl2 = BaSO4 + 2NaCl
white precipitate
B. (BrPh). To the suspension obtained during reaction (a), add 0.1 ml of 0.05
M iodine. The suspension remains yellow (distinction from sulphites and
dithionites), but is decolorised by adding dropwise stannous chloride solution R
(distinction from iodates). Boil the mixture. No coloured precipitate is formed
(distinction from selenates and tungstates).
B. (BrPh, SPU, add. 1). Reaction with sulphuric acid. Wash the residue
collected in the preceding test with 3 successive small quantities of water R. To the
residue add 5 ml of dilute hydrochloric acid R, filter and add to the filtrate 0.3 ml of
dilute sulphuric acid R. A white precipitate is formed that is insoluble in dilute sodium
hydroxide solution R.
BaCO3 + 2HCl = BaCl2 + H2O + CO2
BaCl2+ H2SO4 = BaSO4 + 2HCl
white precipitate
OTHER REACTION:
Pyrochemical reaction. All salts of Barium burns a yellow-green colour.
2. Reaction with solution of potassium chromate K2CrО4 or potassium
dichromate K2Cr2O7; yellow precipitate of BaCrО4 is formed:
Ba2+ + CrО42– = BaCrО4
ASSAY in the Pharmacopoeia is not presents.
Not Pharmacopoeial method – Ion-exchange chromatography.
Heating BaSO4 in the water at t 70–80 С with ion-exchange
resin H-type (cation exchanger) during 12 hour. Occurrence cation
exchange: cations of Barium Ba2+ adsorbs on cation exchanger, in
the filtrate occurres equivalent quantity of sulphuric acid:
BaSO4 + 2H- cation exchanger  Ba- cation exchanger +
H2SO4\
H2SO4, which formed in the filtrate, titrate with 0,1 М sodium
hydroxide NaOH, as indicator use phenolphthalein and titrate until
occirence pink colour.
H2SO4 + 2NaOH = Na2SO4 + 2H2O
Em(BaSO4 ) = М. m./2
Action and use
Radio-opaque substance used in the investigation of the
gastro-intestinal tract.
Preparation
Barium Sulphate for Suspension.
Ph Eur
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Silver Nitrate
SPU, add. 1
Silver Nitrate
General Notices
(Ph Eur monograph 0009)
Argenti nitras
Argentum nitricum
Lapis infernalis
AgNO3
ээ169.9ээ7761-88-8
DEFINITION
Content
99.0 per cent to 100.5 per cent.
OBTAINING
1. Dilution Silver in the 25% solution of nitric acid:
3Ag + 4HNO3 = 3AgNO3 + NO + 2H2O
2. Dilution Cu-Al alloy in the nitric acid at heating:
AgCu + 4HNO3 AgNO3 + Cu(NO3)2 + NO + 2H2O
Obtained Silver nitrate is nessesery to clear from impurities.
CHARACTERS
Appearance
White or almost white, crystalline powder or transparent, colourless crystals.
Solubility
Very soluble in water, soluble in ethanol (96 per cent).
IDENTIFICATION
A. (BrPh, SPU). 10 mg gives the reaction of nitrates (2.3.1).
Nitrates :
Reaction with nitrobenzene in the presence of sulphuric acid. To a mixture of 0.1 ml
of nitrobenzene R and 0.2 ml of sulphuric acid R, add a quantity of the powdered substance
equivalent to about 1 mg of nitrate (NO3–) or the prescribed quantity. Allow to stand for 5 min.
Cool in iced water and add slowly and with mixing 5 ml of water R, then 5 ml of strong sodium
hydroxide solution R. Add 5 ml of acetone R. Shake and allow to stand. The upper layer is
coloured deep violet.
Not pharmacopoeial reactions:
1. Interaction with diphenylamine in the acid medium (conc. H2SO4) with formation
organic dye dark blue colour (analogical to Nitrites-ions, see NaNO2):
diphenylbenzidine
sulphoimmonium salt of diphenylbenzidine (dye with dark blue colour)
2. Interaction with iron(ІІ) sulphate solution FeSO4 in the concentrated sulphatic-acid
medium H2SO4; brown ring (FeSO4NO) is formatted (in the clock glass):
2NaNO3 + 6FeSO4 + 4H2SO4 = 2NO + 3Fe2(SO4)3 + Na2SO4 + 4H2O
NO + Fe2+ + SO42– [Fe(NO)]SO4
This reaction is possible to make in the tube: to solution of drug add conc. H2SO4, then add
iron(ІІ) sulphate solution FeSO4. On the joint two liquids dark-brown ring of unstable
compound FeSO4NO is formed.
Chemism:
2AgNO3 + H2SO4 = Ag2SO4 + 2HNO3
HNO3 + 3H2SO4 + 6FeSO4 = 3Fe2(SO4)3 + 2NO + 4H2O
FeSO4 + NO = FeSO4NO
B. (BrPh, SPU). 10 mg gives the reaction of silver (2.3.1).
Silver and Silver Compounds:
Reaction with hydrochloric acid. Dissolve about 10 mg of the substance to be
examined in 10 ml of water R or use 10 ml of the prescribed solution. Add 0.3 ml of
hydrochloric acid R1. A curdled, white precipitate is formed that dissolves on addition of 3
ml of dilute ammonia R1.
AgNO3 + HCl = AgCl + HNO3
AgCl + 2NH4OH = [Ag(NH3)2]Cl + 2H2O
From all insoluble halogenides of Silver only for AgCl is characteristic solution in
the ammonium carbonate (NH4)2CO3 :
AgCl + (NH4)2CO3 = [Ag(NH3)2]Cl + H2O + CO2
Not pharmacopoeial reactions:
1. Reaction of “silver mirror”
At addition to ammoniac solution of silver nitrate AgNO3 (Tolens reagent)
formaldehyde solution and heating after fixed time on the tube wall metallic silver scurf in
the form of “silver mirror” is formed:
2AgNO3 + 2NH4OH = [Ag(NH3)2]NO3 + 2H2O
HCНO + 2[Ag(NH3)2]NO3 + H2O = 2Ag + HCOONH4 + NH3 + 2NH4NO3
2. Reaction with potassium chromate solution
At addition to silver nitrate solution AgNO3 solution of potassium chromate K2CrО4
orange-red precipitate of silver chromate Ag2CrО4, is formed. This precipitate is soluble in
the HNO3 and NH4OH, almost insoluble in the CH3COOH:
AgNO3 + K2CrО4 = Ag2CrО4 + 2KNO3
ASSAY
(BrPh, SPU, add. 1). Thiocyanatometry, direct titration. Dissolve 0.300 g in 50
ml of water R, add 2 ml of dilute nitric acid R and 2 ml of ferric ammonium sulphate
solution R2. Titrate with 0.1 M ammonium thiocyanate until a reddishyellow colour is
obtained.
1 ml of 0.1 M ammonium thiocyanate is equivalent to 16.99 mg of AgNO3.
AgNO3 + NH4SCN = AgSCN + NH4NO3
3NH4SCN + FeNH4(SO4)2 = Fe(SCN)3 + 2(NH4)2SO4
Em (AgNO3) = M.m.
STORAGE
In a non-metallic container, protected from light.
Ph Eur
Action and use
Antiseptic.
Preparation
Sterile Silver Nitrate Solution
Ph Eur
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Colloidal Silver for External Use
Colloidal Silver for External Use
General Notices
(Ph Eur monograph 2281)
ээээ9015-51-4
Action and use
Antibacterial.
Ph Eur
DEFINITION
Colloidal metallic silver containing protein.
Content
70.0 per cent to 80.0 per cent of Ag (dried substance).
CHARACTERS
Appearance
Green or bluish-black metallic shiny flakes or powder, hygroscopic.
Solubility
Freely soluble or soluble in water, practically insoluble in ethanol (96 per cent) and in
methylene chloride.
STORAGE
In an airtight container .
Ph Eur
Inorganic preparations of Carbon
Carbon - main component of vegetative and animal
organisms. In earth crust and the nature meets as in a free kind
(graphite, diamond), it is artificial origin - carbin (in USSR)
and bakebol (USA), and as a part of minerals - carbonates:
CaCO3 - calcite; MgCO3 - magnesite; CaCO3ЧMgCO3 dolomite; FeCO3 - siderite, iron spar; (CuOH) 2CO3 malachite. In air 0,03 % of carbonic gas CO2 contain.
In medical practice apply absorbent coal (coal activated),
sodium hydrocarbonate, carbon (IV) oxide..
Carbo activatus
Obtaining
Activated charcoal
С
Coal - a product of decomposition of organic substances.
1. Coal of an animal origin - Carbo animalis, bone coal
(roasting bones of animals), blood coal (blood roasting). Such
coal contains to 80 % of ashes (mineral salts, Сa3 (PO4) 2) and
only 7-10 % of coal ©. For clearing of coal of an animal origin
from ashes, process it the acids, which excess wash away water,
and then dry. After such processing animal coal already contains
of ashes only 5-6 % and to 90 % C, shows high adsorption
ability.
2. Coal of a phytogenesis (vegetable origin) (charcoal)
obtain pyrolysis of wood of hardwood of trees without air access.
Such coal has a small amount of ashes (to 6 %), therefore
does not require additional processing, as coal of an animal
origin.
3. Absorbent coal (Coal activated). For obtaining of coal
activated, applied in medicine, wood or animal coal to processing
superheated water steam (at 100 °С). Thus a time pores is cleared
of resinous impurities, the internal surface considerably increases
and consequently increases adsorption ability. One g coal has an
internal surface to 1000 m2; an ultrapores in diameter
approximately 10-9 m playing an active role in the process of
adsorption; a micropores in diameter 10-3-10-5 m). It
adsorbs on the surface various substances, in particular
heavy metals, phenols, spirits, dyes etc.
Adsorption ability can be increased, adding a debonder
(process of solution ZnCl2, MgCl2, NaOH or H3PO4 with the
subsequent heating to 300-400 °С); thus water steam (H2O)
reacts with the added substances (ZnCl2, MgCl2) with
formation of gas HCl which disappears and loosens coal,
increasing a surface of a pores.
Properties
Coal activated represents a black powder without
a smell and taste. It is insoluble in water and other
solvents.
High quality
The coal activated contains impurity ZnO, MgO.
Also the maintenance of impurity of chlorides Cl 2–,
SO
4
sulphates
heavy metals, Fe, As is regulated.
2–,
S
There should not be impuriy of sulphides
2–,
–
СО
CN
3
carbonates
cyanides
(inadmissible
impurity).
Their revealing:
Application. Adsorbing means.
Apply as adsorbing means at food intoxications (sausage
poison, mushrooms) and at diseases of a gastroenteric path
(at the raised acidity and fermentation in a stomach) - doses
0,5-1 g 3-4 times a day, and also at poisonings of alkaloids,
salts of heavy metals - doses 20-30 g on (single, one-time)
in the form of a suspension in water.
Release forms
Tablets of coal activated Tabulеttae Carbonis
actiwati 0,25 aut 0,5.
Consist: coal activated - 0,25 or 0,5 g
Auxiliary substances - enough.
Tablets – Carbolenum. (73% C, 10%sugar, 12% starch, 5% NaCl).
Sodium hydrocarbonate
Natrii hydrocarbonas
NaHCO3
Natrium hydrocarbonicum
Natrium bicarbonicum
Baking soda
HO
C
NaO
O
Obtaining
1. Rose's method (1801): interaction of carbonic gas CO2 with crystal soda Na2CO3.10
H2O:
Na2CO3.10 H2O + CO2 → NaHCO3 + 9H2O
2. Leblan's method (french a doctor, 1791): obtaining of soda from sodium chloride
NaCl, however it is polluted by impurity of chlorides, calcium sulphide CaS and demands
corresponding clearing.
2. Solve's ammoniac method (belgian engineer, 1863, more economic method): the
concentrated solution of sodium chloride NaCl sate with ammonia NH3 at cooling and
simultaneously under pressure pass through it carbonic gas CO2:
NH3 + CO2 + H2O = NH4HCO3
NH4HCO3 + NaCl = NH4Cl + NaHCO3
Properties
The description. White crystal powder without a smell, the
salty-alkaline taste, steady in a dry premise, slowly decays in damp
air. At heating to 270 °С with formation carbonate sodium
completely decays:
2NaHCO3 → Na2CO3 + CO2+ H2O
Therefore weight loss at calcining (frying), makes not
less than 36,6 % (CO2+ H2O).
At temperature 70 °С in a water solution double salt
Na2CO3*NaHCO3 is formed, and at 100 °С - Na2CO3.
.
Solubility. Soluble in water, practically insoluble in 95
% alcohol. Water solutions have alkalescent reaction (рН
= 8,37), caused by salt hydrolysis:
NaHCO3 + НОН  NaОН + CO2+ H2O
HCO3 – + НОН  ОН– + Н2CO3
Identification
1. Reactions of Na+ (see NaF)
2. Reactions of hydrocarbonate-ion HCO3–:
а) SPU. Interaction with acetic acid СН3СООН
NaHCO3 + СН3СООН = СН3СООNa + CO2↑ + H2O
CO2 + Ва(ОН)2 = BaCO3↓ + H2O
BaCO3 + 2HCl = BaCl2 + CO2 + H2O
b) SPU, N. Reaction with saturated solution of magnesium
sulphate MgSO4 at the boiling:
2NaHCO3 → Na2CO3 + CO2 + H2O
4MgSO4 + 4Na2CO3 + 4H2O =
3MgCO3.Mg(ОН)2.3H2O↓ + 4Na2SO4 + CO2
c) SPU, N Solution colouring by means of phenolphtalein.
To a water solution of a preparation add a solution of phenolphtalein; the
solution remains colourless or becomes poorly pink (difference from the
carbonates which solutions get red colouring).
By means of reactions is possible in the conditions of a drugstore to
distinguish hydrocarbonates from carbonates.
ASSAY. Acidimetry, direct titration
T – standart solution of HCl
Ind – methyl orange
Titrate until pink colour.
NaHCO3 + HCl = NaCl + CO2 + H2O
Em(NaHCO3) = M.м.
If in a preparation there is an impurity of sodium carbonate
Na2CO3 results will be overestimated.
Storage. In well corked banks, in a cool and dry place. Under
the influence of damp air passes in sodium a carbonate.
Application. Antiacid agent.
Apply sodium a hydrocarbonate in quality antiacid agent at the raised
acidity of gastric juice, a stomach ulcer of a stomach and duodenum..
However at neutralization of hydrochloric acid carbonic gas which again
stimulates secret allocation is allocated. Therefore it accept together with
enveloping and adsorbing substances which reduce this collateral action.
Accept inside in mixtures in quality expectorant in powders (0,5-1 g)
some times in day.
outwardly apply in the form of 0,5-2 % of water solutions to
inhalations, washings, rinsings a nose, stomatitises, a laryngitis. Use 2
%-s' solution of baking soda for washing of eyes and mucous membrane
of the top respiratory ways at hit on them of acids.
At expressed acidosis enter intravenously - 50-100 ml 3-5 % solutions.
Release forms: a powder, tablets of sodium of hydrocarbonate
Tabulettes Natrii hudrocarbonas 0,3 aut 0,5; a solution of sodium
of a hydrocarbonate 5 %-s' for injection, suppository - 0,3, 0,5 and
0,7 g.
Thanks for attention!