CALCIUM CARBONATE ENCRUSTATION TEST
Another form of deposition that affects the laundering result is the escrustation of fabric with limestone deposits from the reaction of soluble minerals in water with sodium carbonate in the detergent. This deposition occurs along with, and interacts with, the redeposition of soil. Additives which modify the CaCO3crystals to a less adherent form or that inhibit their precipitation are used. A screening test for the encrustation tendencies of detergents containing sodium carbonate and a modification with the addition of soil follows:
PROCEDURE:
Swatches of prewashed cotton cloth are laundered ten consecutive times with hard water solutions of the experimental detergent. The Terg-O-Tometer is used for the laundry cycle and the swatches are dried in an oven. Calcium carbonate deposition is measured at 0, 1, 5 and 10 cycles. EDTA titration of the HCl extract of the swatches is used to measure the amount of limestone deposition.
Soil affects the encrustation phenomenon and soils can be added to study their effects. A combined encrustation and soil redeposition test can be run in the Terg-o-Tometer to measure both kinds of deposition by adding the two soils used in the redeposition test. Reflectance is used to follow soil redeposition.
CONDITIONS:
Temperature 100ºF (38ºC) Detergent Concentration 2 g/L Water Hardness 300 ppm (2/1 Ca/Mg) Detergent Dissolve Time 2 minutes Terg-O-Tometer Speed 100 cpm Rinse Time 5 minutes Wash Time 10 Minutes
Wash Load 12 - 3"X4" clean cotton #400 with fresh coded swatches added to replaced those removed for analysis after 1 and 5 cycles. Drying conditions: 170oF in circulating oven for 15 minutes between wash cycles. Limestone deposition is determined as CaCO3 weight % after drying to constant weight at 100O C. A triple extraction of the swatch with 25 ml of 0.2 N HCl is used to get complete extraction of the CaCO3 deposit. An aliquot of the extract is titrated with EDTA.
TEST FORMULATIONS FOR ADDITIVES: 2g/L or 1g/L
LAS active basis 12% 15% Zeolite A 25 25 Nonionic 6 7 CMC 1-2 1-3 Na Silicate, RU as is 10 10 Polymer 1-5 1-5 Na Carbonate 25 25 Contact George C. Feighner for additional information.
Another form of deposition that affects the laundering result is the escrustation of fabric with limestone deposits from the reaction of soluble minerals in water with sodium carbonate in the detergent. This deposition occurs along with, and interacts with, the redeposition of soil. Additives which modify the CaCO3crystals to a less adherent form or that inhibit their precipitation are used. A screening test for the encrustation tendencies of detergents containing sodium carbonate and a modification with the addition of soil follows:
PROCEDURE:
Swatches of prewashed cotton cloth are laundered ten consecutive times with hard water solutions of the experimental detergent. The Terg-O-Tometer is used for the laundry cycle and the swatches are dried in an oven. Calcium carbonate deposition is measured at 0, 1, 5 and 10 cycles. EDTA titration of the HCl extract of the swatches is used to measure the amount of limestone deposition.
Soil affects the encrustation phenomenon and soils can be added to study their effects. A combined encrustation and soil redeposition test can be run in the Terg-o-Tometer to measure both kinds of deposition by adding the two soils used in the redeposition test. Reflectance is used to follow soil redeposition.
CONDITIONS:
Temperature 100ºF (38ºC) Detergent Concentration 2 g/L Water Hardness 300 ppm (2/1 Ca/Mg) Detergent Dissolve Time 2 minutes Terg-O-Tometer Speed 100 cpm Rinse Time 5 minutes Wash Time 10 Minutes
Wash Load 12 - 3"X4" clean cotton #400 with fresh coded swatches added to replaced those removed for analysis after 1 and 5 cycles. Drying conditions: 170oF in circulating oven for 15 minutes between wash cycles. Limestone deposition is determined as CaCO3 weight % after drying to constant weight at 100O C. A triple extraction of the swatch with 25 ml of 0.2 N HCl is used to get complete extraction of the CaCO3 deposit. An aliquot of the extract is titrated with EDTA.
TEST FORMULATIONS FOR ADDITIVES: 2g/L or 1g/L
LAS active basis 12% 15% Zeolite A 25 25 Nonionic 6 7 CMC 1-2 1-3 Na Silicate, RU as is 10 10 Polymer 1-5 1-5 Na Carbonate 25 25 Contact George C. Feighner for additional information.