Formation of hydrotalcite in mixtures of aluminum hydroxycarbonate and magnesium hydroxide gels.
IR and X-ray analysis demonstrate that hydrotalcite forms during the aging of aluminum hydroxycarbonate gel and magnesium hydroxide gel mixtures. The formation of hydrotalcite produces a change in the pH-stat titrigram and a sharp increase in the pH of the mixture. Hydrotalcite was noted earlier in mixtures having a high molar ratio of magnesium to aluminum, a high total gel concentration, a high initial pH, or in mixtures stored at elevated temperatures. The addition of sorbitol to the mixtures substantially delayed the appearance of hydrotalcite. Nonacid-reactive hydrotalcite formed when mixtures of chloride-containing aluminum hydroxide gel and magnesium hydroxide gel were aged.
D000536:Aluminum Hydroxide / Q000032:analysis*; D002626:Chemistry, Pharmaceutical; D004338:Drug Combinations; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000032:analysis*; D008276:Magnesium Hydroxide / Q000032:analysis*; D013055:Spectrophotometry, Infrared; D013997:Time Factors; D014961:X-Ray Diffraction
D004338:Drug Combinations; C010467:hydrotalcite; C025173:basic aluminum carbonate gel; D000536:Aluminum Hydroxide; D008274:Magnesium; D008276:Magnesium Hydroxide