Preparation method and application of naphthalene sulfonate-alkyl naphthalene sulfonate-formaldehyde condensate

Abstract

The invention discloses a preparation method of a naphthalene sulfonate-alkyl naphthalene sulfonate-formaldehyde condensate. The preparation method comprises the following steps: firstly enabling naphthalene and an alkylation reagent to generate a mixed solution of naphthalene and alkyl naphthalene under the catalysis of sulfuric acid; then adding sulfuric acid into the mixed solution of naphthalene and alkyl naphthalene, and performing the sulfonation reaction; and adding formaldehyde, performing the one-pot condensation, and preparing thea naphthalene sulfonate-alkyl naphthalene sulfonate-formaldehyde condensate. By adopting the preparation method, the naphthalenesulfonic acid and alkyl naphthalene sulfonate do not need to be prepared independently, and the operation is simple; the wasteacid does not need to be removed, no acidic waste water is produced, and safety and environmental protection can be realized; and the prepared naphthalene sulfonate-alkyl naphthalene sulfonate-formaldehyde condensate is used as a dispersing agent to be applied to pesticide water dispersion granules or suspension, and has higher suspension rate and better heat storage stability.

Description

technical field [0001] The invention relates to the technical field of pesticide formulation processing, and more specifically relates to a preparation method and application of a naphthalenesulfonate-alkylnaphthalenesulfonate-formaldehyde condensate. Background technique [0002] Naphthalene sulfonic acid formaldehyde condensate is an anionic surfactant with good emulsifying, dispersing, wetting and penetrating properties. It is widely used in leather, dyes, pesticides, construction concrete and other industries. Among them, sodium naphthalenesulfonate-sodium alkylnaphthalenesulfonate-formaldehyde condensate dispersants are more excellent in all aspects than single monomer naphthalenesulfonic acid or alkylnaphthalenesulfonic acid and formaldehyde condensate dispersants. performance. At present, the method for preparing sodium naphthalenesulfonate-alkylnaphthalenesulfonate-formaldehyde condensate at home and abroad mainly contains the following steps: 1) naphthalene and sul...

AI Technical Summary

Problems solved by technology

[0003] But, in the existing preparation method, naphthalene alkylation, sulfonation mainly have two kinds of approaches, all there is obvious defect: 1) use alkyl alcohol as alkylation reagent, oleum as sulfonation agent and alkylation Catalyst, alkylation and sulfonation are carried out at the same time, and the end of the reaction needs to stand and stratify to separate the spent acid. For example, the Chinese patent with publication number CN107602421A discloses a preparation process of naphthalenesulfonic acid and butylnaphthalenesulfonic acid formaldehyde condensate , wherein after naphthalene and n-butanol are mixed, add dropwise the mixed acid of sulfuric acid and oleum, after the heat preservation reaction, leave it to stand layered and separate the spent acid to obtain butyl naphthalene sulfonic acid; however, this process uses a large amount of acid, not only Increase the cost of raw materials, increase the workload of acid removal, produce a large amount of acid waste water, pollute the environment, increase the step of standing and layering, and make the operation cumbersome

2) The alkylation of naphthalene and the alkylating agent is completed first, and then the alkylated naphthalene is separated for sulfonation. In this process, the alkylation reaction is reported to be a solid acid and ionic liquid catalyzed process, which can obtain relatively high selectivity and purity. However, the catalyst is easily deactivated by the influence of raw materials, and it is expensive, has high requirements for raw materials, and complicated processes, making it difficult to realize industrialization

Images