PROCESS FOR THE FRACTIONATION OF HUMINATES

摘要

A low-molecular-weight huminate fraction is obtained by metering an alkaline substance into an aqueous suspension of huminate-containing products with stirring such that the pH does not exceed 7, continuing to stir the suspension until the pH remains constant, then allowing the mixture to settle, and separating off the substantially solid-free solution, and then centrifuging it and subjecting the clarified solution thus obtained to ultrafiltration.