The Production Process of 1,4-Naphthalenediol, 2-methyl-, 1,4-bis(hydrogen sulfate), sodium salt (1:2)

1,4-Naphthalenediol, 2-methyl-, 1,4-bis(hydrogen sulfate), sodium salt (1:2) is an important intermediate chemical widely used in the production of various chemicals, plastics, and dyes.
The production process of this chemical involves several steps, including the synthesis of 1,4-naphthalenediol and its subsequent modification with sulfuric acid.

The synthesis of 1,4-naphthalenediol is the first step in the production process.
This compound is synthesized by the condensation of 1,4-naphthalene with formaldehyde in the presence of an alkaline catalyst.
The reaction involves the dehydration of formaldehyde to form para-formaldehyde, which then undergoes nucleophilic substitution with the aromatic hydroxyl group of 1,4-naphthalene.
The resulting 1,4-naphthalenediol is then purified and used as the starting material for the subsequent modification with sulfuric acid.

The sulfuric acid modification of 1,4-naphthalenediol involves the addition of sulfuric acid to the diol molecule, resulting in the formation of the desired bis(hydrogen sulfate) salt.
The reaction is typically carried out in a batch reactor, with the 1,4-naphthalenediol and sulfuric acid being added to the reactor as solids.
The reaction is exothermic and requires careful temperature control to prevent excessive heating.

After the reaction is complete, the resulting slurry is filtered to remove any solids and then washed with water to remove any remaining sulfuric acid.
The filtered solution is then concentrated under vacuum to remove any remaining water and produce a concentrated solution of the bis(hydrogen sulfate) salt.

The next step in the production process is the purification of the bis(hydrogen sulfate) salt.
This is typically done by precipitating the salt as a hydrated oxide or hydroxide with a strong acid, such as hydrochloric acid or sulfuric acid.
The resulting precipitate is then filtered, washed with water, and dried to remove any remaining impurities.

The final step in the production process is the recrystallization of the purified bis(hydrogen sulfate) salt.
This is done by dissolving the salt in a suitable solvent, such as water or a polar organic solvent, and then slowly adding a suitable recrystallization agent, such as sodium hydroxide or barium hydroxide.
The resulting solution is then allowed to cool slowly, and the crystals are allowed to precipitate and settle to the bottom of the container.
The crystals are then filtered, washed with water, and dried to produce the final product.

In summary, the production process of 1,4-Naphthalenediol, 2-methyl-, 1,4-bis(hydrogen sulfate), sodium salt (1:2) involves several steps, including the synthesis of 1,4-naphthalenediol, its modification with sulfuric acid, and the subsequent purification and recrystallization of the resulting bis(hydrogen sulfate) salt.
The production of this chemical requires careful attention to detail and the use of appropriate equipment and materials to ensure the highest quality product.