Pseudo-boehmite, manufacturing process and application thereof

A manufacturing process of pseudo-boehmite, comprising:

• contacting an alkaline aluminium source, a cation-exchange resin, and an organic acid source in the presence of water to obtain a mixed liquid, wherein the organic acid source is selected from at least one of mono-C9-C15-alkylether phosphoric acid ester, mono-C9-C15-alkylphosphoric acid ester, di-C9-C15-alkylphosphoric acid ester, and di-C9-C15-alkylether phosphoric acid ester;
• and
• separating the mixed liquid to obtain the pseudo-boehmite, wherein a weight ratio of the alkaline aluminium source, calculated based on alumina, to the organic acid source is 1.2:1 to 24:1,
• wherein the contacting step comprises:
• S1:
• reacting the alkaline aluminum source, the organic acid source, and a first portion of the cation-exchange resin in the presence of water in a reactor to obtain a first mixture having a pH value of 7.5-10;
• and
• S2:
• aging the first mixture, and then adding thereto a second portion of the cation-exchange resin to obtain the mixed liquid having a pH value of 6.5-7.5, and
• wherein the separating step comprises:
• S3:
• separating the cation-exchange resin from the mixed liquid to obtain a slurry;
• S4:
• separating the slurry to obtain a filtrate and a filter cake;
• and
• S5:
• drying the filter cake to obtain the pseudo-boehmite,
• wherein the filter cake is not washed, and the pseudo-boehmite contains a dry content of 55-85 wt %, no more than 0.5 wt % of sodium oxide, 1.2-5.7 wt % of the organic acid source, calculated based on phosphorous pentoxide, relative to 100 wt % of a total weight of the pseudo-boehmite,
• wherein the alkaline aluminium source is selected from aluminate, metaaluminate, and sodium metaaluminate,
• wherein the organic acid source is of formula (I),
• wherein each A is identical to or different from each other, each independently selected from hydrogen ion, ammonium ion (NH4+), metal ion, and a group of formula
• R0 is an optionally substituted C9-15 linear or branched alkyl, n groups R1 are, identical to or different from each other, each independently selected from C1-6 linear or branched alkylene, n is a number in the range of 0 to 200,
• wherein the cation-exchange resin is an acidic cation-exchange resin, a weight ratio of the first portion and the second portion of the cation-exchange resin is 4:1 to 8:1,
• in S1, the reaction temperature is 45° C.-80° C.,
• in S2, the aging temperature is 50-100° C., the ageing time is 0.5-3 hours, and
• an amount of water is 5-20 vol % of the total volume of the reactor.