Sulfuric acid equivalent weight

Vacuum-still bottoms from the H-coal liquefaction process were separated into acid, neutral, and basic fractions by precipitation with acids or by extraction with bases. About one-third of the preasphaltene and one-sixth of the asphaltene fraction were precipitated by acids equivalent weights of the bases were in the range 1200-1800 for preasphaltenes and 600-800 for asphaltenes. The acidic components were obtained either by extraction with aqueous sodium hydroxide or by extraction with benzyltrimethylammonium hydroxide in methanol. About one-fifth of the asphaltene and one-fourth of the presasphaltene fractions were obtained as acids, and up to 10% as amphoteric substances. Nitrogen and sulfur were present in all fractions found. Deno axidation (CF3C02H, H202, H 04) gave dicarboxylic acids from malonic to adipic in addition to mono acids. 

No. The equivalent weight of sulfuric acid is different from that of hydrochloric acid, but it does not enter into the calculation. 

The isolated dimethyl sebacate can be sold commercially as is or optionally hydrolyzed to sebacic acid. If a higher molecular weight plasticizer diester is required, a transesterification with -ethyl hexanol, for example, gives the desired product plus two equivalents of methanol which is recycled back to the oxycarbonylation reaction. If the free acid is desired, dimethyl sebacate hydrolysis to sebacic acid is carried out using a strong mineral acid such as sulfuric acid. Hydrolysis is nearly quantitative with a selectivity of about 99.5% to diacid and. 5% to the half-ester acid product. Additional recrystallization is used to improve purity if required. 

If R is foe burette reading, W is the weight of acid in 100ml of soln, NF is the normal factor of the NaOH soln, 49.043 is the equivalent weight of H Da(1A of mol wt),. then the percentage of sulfuric acid as HaS04 is determined by the following formula ... 

Only rarety is the sulfate of the nitrated base so insoluble that it separates directly on dilution of the reaction mixture as in the above example. In many cases, the hydrochloride can be precipitated by the addition of salt. Frequently, however, it is necessary to neutralize the entire amount of sulfuric acid in order to isolate the product, but this cannot be done with lime because then calcium sulfate would be precipitated with the base. In industrial preparations, tlie neutralization is done with magnesia, of which only a small amount is required because of its low equivalent weight, or with ammonia. In the latter case, the filtrate is treated with lime and the ammonia is recovered and used again. It is preferable to cany out the neutralization in steps, because most of the impurities are precipitated mst, and the later fractions are pure. 

Preparation. Rondestvedt and BordwelF cooled 800 g. of ethylene dichloride and distilled in sulfur trioxide from 60% fuming sulfuric acid or Sulfan B to a gain in weight of 300 g. The sulfur trioxide solution was cooled below —5°, and dioxane equivalent to the sulfur trioxide was added dropwise with stirring, when the complex separated as fine granules. This complex is much more reactive than sulfur trioxide-pyridine it is hydrolyzed by cold water. 

The reactor was charged under a nitrogen atmosphere with an aqueous solution of initiator, buffers, and surfactant, followed by comonomer. The synthesis was then carried out at 60 C with a continuous feed of TFE to maintain the desired pressure in the stirred reactor. After the required quantity of TFE was added, the reactor was vented and the copolymer was isolated by acid coagulation, washed, and dried. The comonomer TFE ratio was adjusted to a level that would produce 80-90 grams of polymer at about 50% conversion of comonomer. The TFE pressure was controlled to produce polymers which analyzed at 1200, 1000, 800 and 600 (+-26) equivalent weight, respectively. Equivalent weights were determined by functional group hydrolysis and titration and confirmed by percent sulfur analysis. 

Recent laboratory studies have shown that the reaction probability 7 can depend strongly on the physical nature, the chemical composition of the aerosols, and hence on the atmospheric temperature and concentration of water vapor and other chemical compounds (e.g., HC1). Figure 2.5 shows the reaction probability as a function of temperature (and equivalently of the weight percentage of sulfuric acid) for the following key stratospheric heterogeneous processes on liquid sulfate aerosols ... 

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