A method for separating bitumen from tar sand by solvent extraction with efficient separation of water from the recovered bitumen is disclosed. Tar sand may often be recovered by surface mining techniques. The tar sand is comprised of bitumen, water and sand including clays. The tar sand is contacted with bitumen solvent having a freezing point below that of the water, and the temperature of the mixture is lowered below the freezing point of the water in the tar sand. The solid ice crystals may then be easily removed along with the sand leaving a water-free liquid bitumen solvent mixture.
A new radioenzymatic assay for catecholamines utilizing the catechol-O-methyl transferase transfer of a methyl group from a labeled methyl donor to the catecholamines followed by isolation of the O-methylated(.sup.3 H)catecholamine and the subsequent measurement of radioactivity.
A method for separating collidal zeolite crystals from aqueous mother liquor solutions with conventional filtration apparatus by initially freezing the dispersion to a slush and conducting the filtration operation as the slush melts.
A process and apparatus for separating tar from a tar sand mixture. The separating step is by a novel mechanical process avoiding the complication of heating, freezing and the use of solvents. In the process a suitable suspension liquid is added to a tar sand mixture which is then struck with a plurality of striker arms to separate tar from said particles and agglomerate tar into droplets. After the striking step, the sand particles are allowed to settle to the bottom and tar droplets rise and float, the tar droplets are skimmed off the mixture, and the tar droplets are also scraped off the striker arms. The resulting tar droplets are washed at least once to remove remaining sand particles.
