Potassium hydrogen sulfate

Sulfuric acid (H2SO4) and phosphoric acid (H3PO4) are the acids most frequently used m alcohol dehydrations Potassium hydrogen sulfate (KHSO4) is also often used... 

Iron oxides are stable pigments iasoluble ia most solvents but usually soluble ia hydrochloric acid. Those not soluble ia HCl can be fused with potassium hydrogen sulfate, KHSO, and then dissolved ia water. 

Ethyl Acetate. Catalysts proposed for the vapor-phase production of ethyl acetate include siUca gel, zirconium dioxide, activated charcoal, and potassium hydrogen sulfate. More recendy, phosphoric-acid-treated coal (65) and calcium phosphate (66) catalysts have been described. 

Alcohol A (CioHi O) is converted to a mixture of alkenes B and C on being heated with potassium hydrogen sulfate (KHSO4). Catalytic hydrogenation of B and C yields the same product. Assuming that dehydration of alcohol A proceeds without rearrangement, deduce the structures of alcohol A and alkene C. 

Oxone Peroxymonosulfuric acid, monopotassium salt, mixt. with dipotassium sulfate and potassium hydrogen sulfate (9) (37222-66-5)... 

Potassium persulfate can be prepared by electrolysis of a mixture of potassium sulfate and potassium hydrogen sulfate at a high current density ... 

Also, the compound can be prepared by adding potassium hydrogen sulfate, KHSO to an electrolyzed solution of ammonium hydrogen sulfate, NH4HSO4... 

C insoluble in water, ethanol and practically all acids soluble in hydrofluoric acid solubdized by fusion with caustic potash or potassium hydrogen sulfate. 

Dehydration procedures have led to 2//-thiopyrans. Thus unsubstituted parent heterocycle 6 was prepared by the dehydration of hydroxy derivative 287 with potassium hydrogen sulfate.20 The same procedure applied to a mixture of isomeric hydroxy 2-methyl-5,6-dihydro-2//-thiopyrans and 3,5-dihydroxy-2,4,5,6-tetrahydrothiopyran gives all the corresponding thio-pyrans.91 3-Phenylthiopyran dioxide 289 was obtained after the dehydration of hydroxy derivative 288a with phosphoric acid at elevated temperatures.300,301 The same approach was explored for the preparation of furano-2//-thiopyran 14.42... 

Preparation by Anodic Oxidation.—When potassium hydrogen sulfate ionizes, we may consider the ions -°v... 

In the tube T, place a solution of potassium hydrogen sulfate saturated at about 0° or made by saturating a solution of sulfuric acid of density 1.3 with normal potassium sulfate, K2S04. Fill the beaker B with ice and water. Use three storage cells and secure a voltage across the terminals of about 6.75 volts and a current density of 1 amp. per square centimeter. 

As expected, a solution of potassium hydrogen sulfate is a strong base and may be titrated with a solution containing HjSOj ions. Such a titration may readily be followed conductometrically with a minimum in conductivity at the neutralization point.8... 

Dehydration of thiochroman-4-ols, generally with potassium hydrogen sulfate, is the most convenient preparation of 2/f-l-benzothio-pyrans,266,267 [Eq. (29)]. Further methods to derivatives of 4 involve the Vilsmeier formylation of thiochroman-4-one to (8-chlorovinyl aldehydes... 

Dehydration of isochromanols has to be carried out with care because of the relative ease with which the resulting isochromenes undergo polymerization under acidic conditions. Potassium hydrogen sulfate is a suitable reagent in some cases, and p-toluenesulfonic acid has also been used (71MI22400). The initial hydroxy compounds are available from iso-chromanones by reduction or by the action of a Grignard reagent. 

CINNAMIC ACID, CINNAMALDEITYDE AND CINNAMYLALCOHOL] (Vol 6) Potassium hydrogen sulfate... 

NIOBIC ACID. Any hydrated form of Nb Os. It forms as a white, insoluble precipitate when a potassium hydrogen sulfate fusion of a niobium compound is leached with hot water or when niobium fluoride solutions are treated widi ammonium hydroxide. Soluble in concentrated sulfuric acid, concentrated hydrochloric acid, hydrogen fluoride, and bases. Important in analytical determination of niobium. See also Niobium. 

Sulfates. Potassium sulfate. [CAS 7778-80-5], sulfate of potash, K2.SO4, white solid, soluble. Common constituent of potassium salt minerals. Used (l)as an important potassium fertilizer, (2) in the preparation of potassium or potash alums potassium hydrogen sulfate, KHSO4, white solid, soluble potassium pyrosulfate. K2S2O7, white solid, soluble, formed by heating potassium hydrogen sulfate to complete loss ot H2O. See also Fertilizer. 

Methylpropene can be removed from the reaction mixture by distillation and easily is made the principal product by appropriate adjustment of the reaction conditions. If the 2-methylpropene is not removed as it is formed, polymer and oxidation products become important. Sulfuric acid often is an unduly strenuous reagent for dehydration of tertiary alcohols. Potassium hydrogen sulfate, copper sulfate, iodine, phosphoric acid, or phosphorus pentoxide may give better results by causing less polymerization and less oxidative degradation which, with sulfuric acid, results in the formation of sulfur dioxide. 

Benzo[6]thienylethylenes are readily obtained by elimination of water from the appropriate alcohol. For example, 3-vinylbenzo[6]-thiophene is conveniently prepared by heating l-(3-benzo[6]thienyl)-ethanol with potassium hydrogen sulfate469,471 or by heating 2-(3-benzo[6]thienyl)ethanol with molten alkali.470 2-Vinylbenzo[fe]thio-phene is obtained by pyrolyzing the acetate of l-(2-benzo[6]thienyl)-ethanol.466,620 Other benzo[6]thiophene alcohols have been dehydrated by heating them with oxalic acid,483 iodine,358,465,467,528 or potassium hydrogen sulfate,465,467 or alone.349,485... 

In the digestion procedure, 6 ml of acidified 12.5% m/v potassium hydrogen sulfate is placed in a PTFE lined screw-cap bottle together with four grams of oven-dried plant material. The uncapped bottle is subjected to the following regime. 

There is distinct evidence that much-improved recoveries of cobalt and molybdenum from grains and grass can be obtained by using nitric acid in conjunction with potassium, hydrogen sulfate or sulfuric acid ashing acids and oxygen enrichment. 

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