Process for making bleach activator
AssigneeEthyl Corporation
InventorsJames S. Staton, Patrick C. Hu
Life of this patent
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Abstract
A manganese exchanged Zeolite A laundry bleach activator is made in a single reaction vessel by mixing dry Zeolite A with an inorganic acid in an amount to lower the pH to 8.0-10.5, adding and mixing in an aqueous manganese (II) salt, adding and mixing in a chelating agent such as sodium tripolyphosphate, adding and mixing in a binding agent such as carboxymethylcellulose, mixing and adding water to cause the Mn-exchanged Zeolite A, chelating agent and binder to agglomerate to form small granules and drying the resulting small granules for use as a bleach activator in laundry detergent compositions.
Claims14
A process of making a manganese (II) exchanged zeolite for use as an activator for a peroxygen laundry bleach, said process comprising:
- (a) adding about 1000 parts by weight of Zeolite A powder to a mixing vessel;
- (b) slowly adding about 100-600 parts by weight of sulfuric acid which contains an amount of H.sub.2 SO.sub.4 sufficient to lower the pH of the mixture to about 7.0-10.5 while mixing to obtain a damp Zeolite A powder;
- (c) slowly adding an aqueous maganese (II) salt solution in an amount to provide 2-50 parts by weight of manganese per 1000 parts of initial Zeolite A while mixing to form a damp Mn-exchanged Zeolite A;
- (d) without separating or drying said solid damp Mn-exchanged Zeolite A, adding and mixing in about 50-1500 parts by weight of a chelating agent;
- (e) adding and mixing in a binding agent in an amount sufficient to provide the desired physical properties;
- (f) slowly adding water in an amount sufficient to agglomerate the blend into small granules while mixing;
- and
- (g) drying the granules to obtain a peroxygen bleach activator.
A process for making a manganese (II) exchanged zeolite for use as an activator for a peroxygen laundry bleach, said process comprising:
- (a) adding about 1000 parts by weight of Zeolite A to a mixing vessel,
- (b) spraying said Zeolite A with 3-10 weight percent aqueous sulfuric acid while mixing and in an amount to adjust the pH of the mixture into the range of 7-10.5 and to form a damp Zeolite A powder,
- (c) spraying said dump Zeolite A powder with an aqueous Mn (II) salt solution containing about 2-30 weight percent of Mn (II) cations while mixing and in an amount which provides about 2-50 parts by weight of Mn (II) cations for each 1000 parts of said Zeolite A and forms a damp Mn-exchanged Zeolite A,
- (d) without separating or drying said damp Mn-exchanged Zeolite A, adding and mixing in a chelating agent,
- (e) adding and mixing in a binding agent in an amount to provide an agglomerated final product upon addition of water,
- (f) mixing the blend vigorously while adding water if required to cause the blend to agglomerate into small granules of about 2-200 mesh and
- (g) drying said small granules to obtain a per oxygen bleach activator.
Dependencies are inferred from the claim text.