Triple pressed palm stearic is typically used in paraffin wax candles for hardness and opacity. Commonly used in pillar/molded candles at approx 3-5% to help release the paraffin from the moulds.
It can be added to candles to harden the wax and improve fragrance retention. Use at a rate of 1 - 3%. Being a hardener it will cause wet spotting. You may need to wick up so test burning is essential. Too much stearic will bind your fragrance and you will loose fragrance throw so caution is needed. Typically stearic acid is not needed in soy candles. Add with your wax at the beginning of the melt process and melt up to 80 degrees + to ensure stearic has melted correctly.
Also used in soaps for hardness, and in lotions as an emollient and thickener. Typical usage rates are around 1-3%.