Title | Date | Subject | Description | ||
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1 | Monitoring surfactant content to control hot water process for tar sand | 1991-04-23 | Patent; Hot water process; Tar sand; Extraction; Surfactants | The present invention is based on the following: (1) that when tar sand is conditioned and diluted in the hot water extraction process, there are two classes of anionic surfactants (originating from carboxylate and sulfonate groups) present in the process water; (2) that each of these surfactants ha... |