Preparation of linear polyethylenepolyamines with an aluminum phosphate catalyst

Claim 1

A method of preparing linear polyethylenepolyamines from ethylenediamine and monoethanolamine which comprises: mixing and reacting ethylenediamine with monoethanolamine at a temperature of about 200° to about 400° C. and a pressure of about 700 to about 1400 psig in the presence of a catalytically effective amount of an aluminum phosphate catalyst; said catalyst prepared by mixing and reacting alumina with phosphoric acid, adding water to the reaction mixture, adding ammonium hydroxide to form a precipitate, continuing the addition of ammonium hydroxide until precipitate formation ceases, and separating the precipitate catalyst from the reaction mixture; and recovering a polyethylenepolyamine product characterized by a relatively large percentage of linear, non-cyclic polyethylenepolyamines.

Claim 2

A method of preparing linear polyethylenepolyamines from ethylenediamine and monoethanolamine which comprises: mixing and reacting ethylenediamine with monoethanolamine at a temperature of about 200° to about 400° C. and a pressure of about 700 to about 1400 psig in the presence of a catalytically effective amount of an aluminum phosphate catalyst; said catalyst prepared by mixing and reacting alumina with phosphoric acid, adding water to the reaction mixture, adding ammonium hydroxide to form a precipitate, continuing the addition of ammonium hydroxide until precipitate formation ceases, and separating the precipitate catalyst from the reaction mixture; and recovering a polyethylenepolyamine product characterized by a relatively large percentage of linear, non-cyclic polyethylenepolyamines.

Claim 8

A method of preparing linear polyethylenepolyamines from ethylenediamine and monoethanolamine which comprises: mixing and reacting about one mole to about two moles of ethylenediamine per mole of monoethanolamine with monoethanolamine at a temperature of about 300° C. to about 350° C. and a pressure of about 700 to about 1400 psig in the presence of from about 5.0 to about 15.0 weight percent aluminum phosphate catalyst, based on the amount of monoethanolamine present; said catalyst prepared by (a) mixing and reacting 85 wt. % phosphoric acid with hydrated alumina in a molar ratio of about six moles of phosphoric acid per mole of alumina, (b) adding sufficient water to the phosphoric acid and alumina reaction mixture to yield a pH of about 2 to 3 for the mixture, (c) adding a 30% ammonium hydroxide solution to the mixture to form a precipitate and continuing addition of the ammonium hydroxide solution until precipitate formation ceases and the pH of the mixture is about 5 to 6, (d) separating the precipitate from the reaction mixture, isolating and drying the precipitate; and recovering a polyethylenepolyamine product characterized by a relatively large percentage of linear, non-cyclic polyethylenepolyamines.

Claim 9

A method of preparing linear polyethylenepolyamines from ethylenediamine and monoethanolamine which comprises: mixing and reacting about one mole to about two moles of ethylenediamine per mole of monoethanolamine with monoethanolamine at a temperature of about 300° C. to about 350° C. and a pressure of about 700 to about 1400 psig in the presence of from about 5.0 to about 15.0 weight percent aluminum phosphate catalyst, based on the amount of monoethanolamine present; said catalyst prepared by (a) mixing and reacting 85 wt. % phosphoric acid with hydrated alumina in a molar ratio of about six moles of phosphoric acid per mole of alumina, (b) adding sufficient water to the phosphoric acid and alumina reaction mixture to yield a pH of about 2 to 3 for the mixture, (c) adding a 30% ammonium hydroxide solution to the mixture to form a precipitate and continuing addition of the ammonium hydroxide solution until precipitate formation ceases and the pH of the mixture is about 5 to 6, (d) separating the precipitate from the reaction mixture, isolating and drying the precipitate; and recovering a polyethylenepolyamine product characterized by a relatively large percentage of linear, non-cyclic polyethylenepolyamines.