Potassium bisulfate

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  • Identifiers

    CAS number
    7646-93-7

    Molecular formula
    HKO4S

    SMILES
    OS(=O)(=O)[O-].[K+]

    Safety labels

    Corrosive
    Corrosive

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Odorless 92.23%
    Pungent 13.61%
    Cooked 13.32%
    Sulfurous 13.06%
    Savory 12.73%
    Clean 12.37%
    Sour 12.23%
    Sharp 11.89%
    Burnt 10.37%
    Roasted 8.83%

     

    Flavor
    Bitter 70.9%
    Odorless 41.43%
    Bland 25.5%
    Formyl 21.18%
    Nitrile 19.95%
    Rotten 19.74%
    Mousy 19.09%
    Urine 18.82%
    Decomposing cabbage 18.11%
    Bread crust 18.0%

     

    Odor impact est.
    Medium

  • Properties

    pKa est.
    3.43 (weak acid)

    Molecular weight
    136.17 g/mol

    Flash point

    • 150.28 ˚C est.

    Solubility expt.

    • Freely soluble in water, insoluble in ethanol
    • Solubility in water, g/100ml: 49 (very good)

  • Synonyms

    • Potassium bisulfate
    • Potassium hydrogen sulfate
    • 7646-93-7
    • Sal enixum
    • Sulfuric acid, monopotassium salt
    • Caswell No. 682C
    • Monopotassium hydrogen sulfate
    • Potassium hydrosulfate (KHSO4)
    • Potassium hydrogen sulfate, solid
    • EINECS 231-594-1
    • UN2509
    • EPA Pesticide Chemical Code 005605
    • NSC 409996
    • UNII-1J1K03241F
    • AI3-04459
    • 1J1K03241F
    • INS NO.515(II)
    • DTXSID8047715
    • POTASSIUM BISULFATE [MI]
    • INS-515(II)
    • E-515(II)
    • NSC-409996
    • POTASSIUM HYDROGEN SULFATE, (SOLID)
    • POTASSIUM HYDROGEN SULFATE, [SOLID]
    • RefChem:175430
    • DTXCID7027708
    • 231-594-1
    • Sulfuric acid monopotassium salt
    • Potassium acid sulfate
    • Potassium hydrogensulphate
    • Potassium bisulphate
    • Monopotassium sulfate
    • Acid potassium sulfate
    • potassium hydrogen sulphate
    • potassium;hydrogen sulfate
    • Kaliumbisulfat
    • kalium hydrogen sulfate
    • potassium hydrogensulfate
    • HKO4S
    • KHSO4
    • potassium hydrogen-sulphate
    • potassium monohydrogensulfate
    • SCHEMBL35941
    • HYDROGEN POTASSIUM SULFATE
    • Potassium hydrogen sulfate (KHSO4)
    • AKOS015950618
    • Sulfuric acid, potassium salt (1:1)
    • AT49831
    • NS00081007
    • F050590
    • Q411108
    • Potassium hydrogen sulfate [UN2509] [Corrosive]
    • Potassium hydrogen sulfate, Trace metals grade 99.95%
    • 7646-93-7

  • Applications

    Potassium bisulfate (CAS 7646-93-7) is used primarily as a source of potassium and sulfur in agriculture, supplying nutrients to crops and forming fertilizer blends for acidic soils. In industrial manufacturing, it serves as a solid acid catalyst or bisulfate acid source to support reactions such as esterification and polymerization. In laboratory and chemical synthesis, it is commonly used as a reagent and a precursor for multiple synthetic routes. In certain food processing operations, it may be used as an acidifying agent to adjust acidity in specific formulations.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 227.03
    methanol 416.05
    isopropanol 174.26
    water 428.04
    ethyl acetate 60.29
    n-propanol 137.26
    acetone 261.98
    n-butanol 104.16
    acetonitrile 147.31
    DMF 1096.66
    toluene 32.61
    isobutanol 89.03
    1,4-dioxane 226.14
    methyl acetate 100.09
    THF 259.35
    2-butanone 120.79
    n-pentanol 71.44
    sec-butanol 105.2
    n-hexane 13.75
    ethylene glycol 225.65
    NMP 491.88
    cyclohexane 20.0
    DMSO 1042.52
    n-butyl acetate 34.9
    n-octanol 40.05
    chloroform 29.25
    n-propyl acetate 46.22
    acetic acid 133.28
    dichloromethane 61.16
    cyclohexanone 101.36
    propylene glycol 139.34
    isopropyl acetate 41.72
    DMAc 664.05
    2-ethoxyethanol 217.38
    isopentanol 77.39
    n-heptane 12.64
    ethyl formate 100.98
    1,2-dichloroethane 74.18
    n-hexanol 46.91
    2-methoxyethanol 419.04
    isobutyl acetate 22.13
    tetrachloromethane 9.29
    n-pentyl acetate 32.52
    transcutol 176.45
    n-heptanol 37.19
    ethylbenzene 16.8
    MIBK 49.76
    2-propoxyethanol 143.55
    tert-butanol 169.29
    MTBE 84.66
    2-butoxyethanol 92.4
    propionic acid 87.41
    o-xylene 32.83
    formic acid 248.95
    diethyl ether 103.62
    m-xylene 24.32
    p-xylene 20.49
    chlorobenzene 19.8
    dimethyl carbonate 104.07
    n-octane 6.5
    formamide 398.93
    cyclopentanone 149.34
    2-pentanone 86.98
    anisole 60.61
    cyclopentyl methyl ether 93.78
    gamma-butyrolactone 156.75
    1-methoxy-2-propanol 270.88
    pyridine 107.05
    3-pentanone 75.23
    furfural 192.47
    n-dodecane 5.4
    diethylene glycol 198.81
    diisopropyl ether 27.72
    tert-amyl alcohol 109.92
    acetylacetone 97.29
    n-hexadecane 5.71
    acetophenone 56.04
    methyl propionate 89.79
    isopentyl acetate 25.36
    trichloroethylene 52.5
    n-nonanol 36.36
    cyclohexanol 70.89
    benzyl alcohol 62.69
    2-ethylhexanol 24.22
    isooctanol 25.67
    dipropyl ether 49.48
    1,2-dichlorobenzene 18.63
    ethyl lactate 53.96
    propylene carbonate 69.33
    n-methylformamide 406.08
    2-pentanol 68.92
    n-pentane 21.62
    1-propoxy-2-propanol 91.07
    1-methoxy-2-propyl acetate 52.44
    2-(2-methoxypropoxy) propanol 87.59
    mesitylene 19.64
    ε-caprolactone 81.52
    p-cymene 13.51
    epichlorohydrin 150.7
    1,1,1-trichloroethane 22.36
    2-aminoethanol 226.47
    morpholine-4-carbaldehyde 399.62
    sulfolane 252.01
    2,2,4-trimethylpentane 6.17
    2-methyltetrahydrofuran 115.25
    n-hexyl acetate 37.7
    isooctane 4.68
    2-(2-butoxyethoxy)ethanol 109.11
    sec-butyl acetate 26.04
    tert-butyl acetate 40.75
    decalin 6.62
    glycerin 240.79
    diglyme 189.87
    acrylic acid 99.51
    isopropyl myristate 22.6
    n-butyric acid 67.23
    acetyl acetate 38.95
    di(2-ethylhexyl) phthalate 26.83
    ethyl propionate 48.94
    nitromethane 278.1
    1,2-diethoxyethane 65.98
    benzonitrile 42.36
    trioctyl phosphate 22.51
    1-bromopropane 41.83
    gamma-valerolactone 216.76
    n-decanol 30.77
    triethyl phosphate 27.64
    4-methyl-2-pentanol 37.1
    propionitrile 86.29
    vinylene carbonate 71.64
    1,1,2-trichlorotrifluoroethane 118.05
    DMS 40.31
    cumene 14.48
    2-octanol 28.27
    2-hexanone 54.66
    octyl acetate 30.65
    limonene 18.94
    1,2-dimethoxyethane 345.45
    ethyl orthosilicate 26.04
    tributyl phosphate 22.99
    diacetone alcohol 80.2
    N,N-dimethylaniline 71.47
    acrylonitrile 116.4
    aniline 66.74
    1,3-propanediol 190.68
    bromobenzene 13.92
    dibromomethane 41.55
    1,1,2,2-tetrachloroethane 53.62
    2-methyl-cyclohexyl acetate 27.07
    tetrabutyl urea 49.67
    diisobutyl methanol 19.53
    2-phenylethanol 40.56
    styrene 21.02
    dioctyl adipate 34.04
    dimethyl sulfate 173.93
    ethyl butyrate 35.65
    methyl lactate 110.52
    butyl lactate 40.4
    diethyl carbonate 28.67
    propanediol butyl ether 83.2
    triethyl orthoformate 32.47
    p-tert-butyltoluene 13.78
    methyl 4-tert-butylbenzoate 58.89
    morpholine 241.08
    tert-butylamine 95.45
    n-dodecanol 26.05
    dimethoxymethane 409.62
    ethylene carbonate 65.33
    cyrene 94.91
    2-ethoxyethyl acetate 43.84
    2-ethylhexyl acetate 20.7
    1,2,4-trichlorobenzene 22.08
    4-methylpyridine 100.58
    dibutyl ether 31.98
    2,6-dimethyl-4-heptanol 19.53
    DEF 176.21
    dimethyl isosorbide 101.87
    tetrachloroethylene 40.05
    eugenol 73.72
    triacetin 45.58
    span 80 63.53
    1,4-butanediol 104.89
    1,1-dichloroethane 38.99
    2-methyl-1-pentanol 47.45
    methyl formate 293.17
    2-methyl-1-butanol 71.63
    n-decane 7.33
    butyronitrile 69.35
    3,7-dimethyl-1-octanol 27.32
    1-chlorooctane 16.01
    1-chlorotetradecane 9.86
    n-nonane 7.5
    undecane 6.1
    tert-butylcyclohexane 5.25
    cyclooctane 9.73
    cyclopentanol 98.28
    tetrahydropyran 110.71
    tert-amyl methyl ether 67.99
    2,5,8-trioxanonane 162.99
    1-hexene 26.24
    2-isopropoxyethanol 118.48
    2,2,2-trifluoroethanol 98.53
    methyl butyrate 63.37

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction