The invention relates to a preparation method for synthetizing a high efficiency water
reducing agent by 2-naphthol waste water. The invention belongs to the technical field of concrete water reducing agents. According to the preparation method for synthetizing the high efficiency water
reducing agent by the 2-naphthol waste water, the proportion of crude
naphthalene to concentrated
sulfuric acid to naphthol waste water to
formaldehyde is (1:0.8)-(1.0:0.1)-(0.9:0.5)-0.8. The preparation method for synthetizing the high efficiency water
reducing agent by the 2-naphthol waste water comprises the following process flows of: 1-, sulfonating: heating to melt crude
naphthalene, adding the concentrated
sulfuric acid when the temperature rises to 130-160 DEG C, and reacting for 2-2.5 hours at the temperature of 160-165 DEG C; 2-, hydrolyzing: cooling reactants to 90-110 DEG C, adding naphthol waste liquor and hydrolyzing for 0.5-1 hour; 3-, condensation: dropwise adding the
formaldehyde at the temperature of 95-115 DEG C and reacting for 3-6 hours; and (4) neutralizing: adding liquid caustic soda to neutralize a condensation compound to regulate a pH value to be 7-9 to obtain a water reducing agent product. The preparation method for synthetizing the high efficiency water reducing agent by the 2-naphthol waste water has the advantages that the production process is simple, the operation is convenient, the
process control is easy, waste is turned into wealth, and thereby,
secondary emission cannot be generated, and the economic value and the social benefit are high and the like.