A process for preparing methacrolein comprising: (a) mixing water and an amine-acid catalyst to provide a catalyst stream; (b) sending the catalyst stream and a reaction stream comprising propionaldehyde, formaldehyde, and methanol to a reactor to produce a first intermediate stream comprising methacrolein, methanol, and at least 8 weight % water; (c) providing the first intermediate stream to a first phase separator to produce (i) a first aqueous phase comprising methacrolein, methanol, amine-acid catalyst, and at least 65 weight % water, and (ii) a first organic phase comprising water, at least 85 weight % methacrolein, and less than 5 weight % methanol; (d) distilling the first aqueous phase in a first distillation column to produce (i) a second intermediate stream comprising methacrolein, water, and less than 60 weight % methanol, (ii) a bottoms stream comprising amine-acid catalyst, and (iii) a side draw stream comprising methanol and water; (e) providing the second intermediate stream and water to a second phase separator to produce (i) a second organic phase comprising methacrolein, water, and less than 55 weight % methanol, and (ii) a second aqueous phase; (f) distilling the first organic phase and the second organic phase in a second distillation column to produce (i) a third intermediate stream comprising methacrolein and less than 2 weight % methanol, and (ii) an overhead stream; (g) distilling the third intermediate stream in a third distillation column to produce (i) a product stream comprising methacrolein and water in a combined amount of at least 97 weight %, less than 2 weight % methanol, and less than 1 weight % of impurities comprising one or more of acetic acid, propionic acid, methacrolein dimer, and 2-methyl-2-pentenal, and (ii) a waste stream; (h) recycling at least part of the overhead stream to the first phase separator; and (i) recycling at least part of the bottoms stream to the catalyst stream. (a) mixing water and an amine-acid catalyst to provide a catalyst stream; (b) sending the catalyst stream and a reaction stream comprising propionaldehyde, formaldehyde, and methanol to a reactor to produce a first intermediate stream comprising methacrolein, methanol, and at least 8 weight % water; (c) providing the first intermediate stream to a first phase separator to produce (i) a first aqueous phase comprising methacrolein, methanol, amine-acid catalyst, and at least 65 weight % water, and (ii) a first organic phase comprising water, at least 85 weight % methacrolein, and less than 5 weight % methanol; (d) distilling the first aqueous phase in a first distillation column to produce (i) a second intermediate stream comprising methacrolein, water, and less than 60 weight % methanol, (ii) a bottoms stream comprising amine-acid catalyst, and (iii) a side draw stream comprising methanol and water; (e) providing the second intermediate stream and water to a second phase separator to produce (i) a second organic phase comprising methacrolein, water, and less than 55 weight % methanol, and (ii) a second aqueous phase; (f) distilling the first organic phase and the second organic phase in a second distillation column to produce (i) a third intermediate stream comprising methacrolein and less than 2 weight % methanol, and (ii) an overhead stream; (g) distilling the third intermediate stream in a third distillation column to produce (i) a product stream comprising methacrolein and water in a combined amount of at least 97 weight %, less than 2 weight % methanol, and less than 1 weight % of impurities comprising one or more of acetic acid, propionic acid, methacrolein dimer, and 2-methyl-2-pentenal, and (ii) a waste stream; (h) recycling at least part of the overhead stream to the first phase separator; and (i) recycling at least part of the bottoms stream to the catalyst stream.