Sulfuric acid heat generation

Bardet Also called Samica. A process for expanding mica in order to make it into paper. It is partially dehydrated by heating and the hot product is quenched in alkaline water. After drying, it is immersed in dilute sulfuric acid, which generates gas between the layers, forcing them apart. In this expanded condition it can easily be made into a paper. 

Sulfur trioxide dissolves in water forming sulfuric acid and generating large heat. 

The mercury reagent blank for the nitric acid cannot be measured by generating elemental mercury from a solution of 1 3 nitric acid with divalent tin. However, it can be determined by adding potassium permanganate and sulfuric acid, heating the solution to remove the nitric acid, and measuring the mercury after treatment with hydroxylamine sulfate. 

Mixing isopropyl ether with concentrated nitric and sulfuric acids can generate heat. Mixing with acid chlorides can be violent. Violent exothermic reaction occurred when propionyl chloride was mixed with isopropyl ether in the presence of trace zinc chloride or ferric chloride (Koenst 1981). 

Ca.ro s Acid. Caro s acid is named after Heinrich Caro (1834—1910), who first described its preparation and oxidi2ing properties ia 1898. Hereia Caro s acid is used to designate the equiUbrium mixtures that result from mixing hydrogen peroxide and sulfuric acid. These Hquids mix iastantly, generating a considerable amount of heat. The equiUbrium constant for this reaction is 0.1 (62). 

Plants producing oleum or Hquid SO typically have one or two additional packed towers irrigated with oleum ahead of the normal SO absorption towers. Partial absorption of SO occurs in these towers, and sulfuric acid is added to maintain desired oleum concentrations. Normally, oleum up to about 35 wt % free SO content can be made in a single tower two towers are used for 40 wt % SO. Liquid SO is produced by heating oleum in a boder to generate SO gas, which is then condensed. Oleums containing SO >40 wt % are usually produced by mixing SO with low concentration oleum. 

A further enhancement to the HRS process whereby the exhaust from a gas fired turbine is used to superheat steam from the HRS process is also possible (129). The superheated steam is then fed through a turbogenerator to produce additional electricity. This increases the efficiency of heat recovery of the turbine exhaust gas. With this arrangement, electric power generation of over 13.6 kW for 1 t/d (15 kW/STPD) is possible. Good general discussions on the sources of heat and the energy balance within a sulfuric acid plant are available (130,131). 

Methyl 2-methoxy-2-polyfluoroalkyl-2-fluoroacetates, generated from poly-fluoroalkyltrifluoroethylene oxides and methanol, give, on heating with concentrated or fuming sulfuric acid, methyl polyfluoroalkylglyoxylates [29] (equation 32). 

To evaluate the heat exchange/productivity performances of the device and its environment, an acid-base neutralization involving sulfuric acid and soda has been performed. It is an instantaneous and exothermic reaction with AH = —92.4 kj moP (NaOH). Each experiment is characterized by the initial concentration of the reactants (from 10 to 30% in mass of soda and from 5 to 12% in mass of sulfuric acid). These concentrations are varied in order to evaluate the behavior of the reactor with respect to different amounts of heat generated (from 0.4 to 1.3 kW). Each run is performed with a variable utility flow rate (from 1 to 3 m h ). 

Accidental ingress of water to the heated mixture liberated sulfuric acid or its half ester which caused a violent reaction with generation of a large volume of solid black foam. 

Nitroaniline reacts almost explosively [1], and 4-nitroaniline, 4-nitroacetanilide, aminonitrobiphenyls, aminonitronaphthalenes and their various derivatives [2], as well as some nitro-N-heterocycles [1,2], also react vigorously. 4-Nitroanilinium sulfate and 4-nitroaniline-2-sulfonic acid and its salts also generate foams when heated without sulfuric acid. The mechanism is not clear, but involves generation of a polymeric matrix foamed by sulfur dioxide and water eliminated during the reaction [1]... 

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