Drain cleaning composition

A pelletized drain cleaning composition wherein each pellet of said composition consists essentially of:

• 1. 1.5 to 12 weight percent aluminum;
• 2. 15 to 51 weight percent of an alkali metal nitrate selected from the group consisting of potassium nitrate, sodium nitrate and mixtures thereof;
• 3. 0.5 to 10 weight percent of a binding material having a melting point of from about 37.degree. C. to about 67.degree. C. selected from the group consisting of polymers of polyethylene glycol, having a molecular weight of from about 3000 to about 20,000;
• polymers of ethylene oxide, having a molecular weight of from about 400,000 to about 2,000,000;
• hydrocarbon oxyethylated straight chain fatty alcohols, having a molecular weight of about 260 to about 265 and containing about 80%, by weight, ethylene oxide;
• fatty acids, having a carbon chain length of from about 10 to about 18 carbon atoms;
• alkali metal salts of gluconic acid selected from the group consisting of sodium gluconate, potassium gluconate and sodium glucoheptonate;
• and mixtures thereof;
• 4. 1 to 10 percent of an alkali metal hydroxide;
• 5. 10 to 60 weight percent of an additional compatible alkaline ingredient selected from the group consisting of alkali metal borates, alkali metal silicates, alkali metal bicarbonates, alkali metal carbonates, alkali metal phosphates and mixtures thereof, whereby the total alkaline concentration present, expressed as sodium oxide, is at least about 11%, by weight;
• wherein
• said alkali metal borates are alkali metal meta-, tetra-borates, or hydrates thereof;
• said alkali metal silicates are alkali metal meta-, ortho-silicates, or hydrates thereof having the formula x(SiO.sub.2) (M.sub.2 O), where x varies from 0.5 to 3.75 and M is an alkali metal;
• and
• said alkali metal phosphates are alkali metal monobasic-, dibasic-, tribasic-, meta-, pyrophosphates, or hydrates thereof;
• 6. up to about 10 weight percent of an oil selected from the group consisting of mineral oils having a viscosity range of about 34 to 360 Saybolt Universal Seconds at 100.degree. F;
• silicone oils selected from the group consisting of dimethylpolysiloxanes having flash points of not less than about 500.degree. F and having a viscosity range of about 40 to 60 centistokes at 25.degree. C;
• vegetable oils having a viscosity range of about 40 to 60 centipoises at 25.degree. C;
• petroleum lubricating oils having a viscosity range of about 100 to 500 centipoises at 25.degree. C;
• and mixtures thereof;
• wherein the amount of oil present is sufficient to coat the aluminum;
• and
• 7. a salt selected from the group consisting of potassium chloride, sodium chloride and mixtures thereof and said salt is present in an amount up to about 48%, by weight;
• wherein said composition is prepared by the method consisting essentially of:
• a. reducing the particle size of all of the ingredients to a size between 40 and 710 microns;
• b. coating the aluminum particles with the oil;
• and draining off the excess oil
• c. adding the excess oil, the alkali metal nitrate, alkaline ingredient, the binder material, and the salt, if any, to the coated aluminum particles of (b) and mixing the ingredients;
• d. adding the alkali metal hydroxide particles to the resulting mixture of (c) and mixing the ingredients;
• e. pelletizing the resulting mixture of (d) at a temperature just above the melting point of the binding material;
• and
• f. cooling the resulting pellets obtained from
• e. said pellets having a size such that they pass through the openings of a U.S. sieve screen having a mesh size of 8 and are retained on a U.S. sieve screen having a mesh size of 20.