Sulpho acids

F. I. Aleev. Oil displacement from heterogeneous seam by pumping sulphuric acid and water to seam—until sulpho-acids appear in liquid removed from wells. Patent RU 2055166-C, 1996. 

The sulpho-salts of arsenic, antimony, and stannic tin are particularly characteristic of these metals. (See Preparation 43 and Experiment 11, page 294.) They are easily produced, and all are soluble. They are stable in neutral or basic solutions, but are decomposed by acids, because the anions of the salts combine with hydrogen ions to produce the very weak sulpho-acids, which, being unstable, decompose at once into the sulphides of the metals and hydrogen sulphide ... 

The product is a sulphuric acid ester or sulpho acid which is susceptible to acid hydrolysis, reverting to the alcohol and free sulphuric acid. Since the rate of hydrolysis is dependent on the concentration of the acid, the hydrolysis reaction is effectively self-catalysing so that the sulpho acid must be neutralised as quickly as possible after manufacture to prevent reversion. This simple chemistry has a profound effect on the manufacture, use and economics of alkyl sulphates. 

The need to neutralise immediately after sulphation also changes the mode of use and the economics of alkyl sulphates compared to LAS which is commonly traded as the free acid at typically 97% active matter. This reduces the price (fewer unit operations, hence lower manufacturing costs) and transport costs per unit of active matter and gives the formulator freedom of choice in counter ion and concentration of the final surfactant. Since this is not possible with AS, the manufacturer must neutralise the sulpho acid, often needing to add a buffer and preservative. (This increases the price paid to the supplier, but not necessarily the total cost of the surfactant in formulation.) Most alkyl sulphates are supplied as 20-30% active solutions, so the transport cost per unit of active matter is 3-5 times higher for LAS. 

Sulpho acids, (mixed e.g. CeH4< sulphonic acids and carboxy acids)... 

Disulpbonic and trisulphonic acids have also been prepared by action of m-diazobenzoic acid and its sulpho-acids on -naphthol-disulphonic acid. Diazoanisic acid, as ivell as the paradiazocin-namic acid and its ethers [51], gives red azo-dyes [49] ivith naphthol acid and its sulphonic acids. 

The indulines are mostly insoluble in water both in form of bases and salts, but are soluble in alcohol. The solutions of the bases are red to reddish violet, the salts are bluish violet, blue, or bluish grey. They are soluble in concentrated sulphuric acid with a pure blue colour, the sulpho-acids have the same colour as the salts of the original induline, and the salts of the sulpho-acids have the same colour as the free bases. 

Early in 1878, Heinrich Caro patented in Germany and England a process for red and brown acidic azo dyes, the sulpho acids of oxyazonaphthaline, prepared from diazotised aminonaphthalene and naphthalene-based coupling components. The... 

Although the Judge who has been trying the action of the Badische Corny v. Dawson has reserved his judgment I think we are Justified in expecting a judgement in the Pits [plaintiffs] favour, upholding the validity of the patent for the sulpho acids of dinitronaphthol. 

B sulphide, sulphoxid, sulphone C sulphoxid, sulphone, sulpho acid Cat sodium molybdate... 

The thermokinetic interpretation of the measured course of the thermal reaction power of the oxidation of sulphide via sulphoxid and sulphon up to sulpho acid is started on a trial basis according to the assumption of quasi-elementary steps, the stoichiometry and (5.1), (4.9), (4.34), with... 

Rearrangement of the relation to the explicit expression iopi = fi ki, 2, 3) is not possible. Nevertheless, because of the elaborated kinetic fact that k 3> k2, k, a direct calculation with sufficient accuracy is possible k 3> k2, k means that the formation of sulphoxid from sulphide occurs - compared with the following relatively slow reactirMis to sulphon and sulpho acid - almost instantly (Fig. 5.10). Because of that, the exact equation (5.19) shrinks in good approximation to... 

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