TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Product: The hydrocarbon product primarily comprises 5-24C hydrocarbons. The Fischer-Tropsch hydrocarbon product (28) is an alkylaromatic sulfonate product comprising linear alkylaromatic sulfonates (at least5 wt.% of the product), and non-linear alkylaromatic sulfonates. It has hydrocarbon compounds having a normal boiling point of 150-700degreesF. It comprises initial linear paraffin content of at least50 wt.% of the hydrocarbon product, and a branched paraffin content of less than 20 wt.% of the hydrocarbon product. Preferred Condition: The ratio of end-chain monomethyl branching to internal branching of the monomethyl branched paraffins is at least1:1, preferably at least2:1. The alkylaromatic sulfonate product has a Kraft temperature of at most50degreesC. Preferred Composition: The n-paraffins are present in an amount of at least20, preferably at least40 wt.% of the hydrocarbon product. The linear alkylaromatic sulfonates are present in an amount of at least20, preferably 40 wt.% of product. Preferred Component: Substantially all the non-linear alkylaromatic sulfonates are monomethyl branched alkylaromatic sulfonates, and all the branched paraffins are monomethyl branched paraffins. The alkylaromatic sulfonates are alkylbenzene sulfonates.    TECHNOLOGY FOCUS - INDUSTRIAL STANDARDS - Preferred Condition: The alkylaromatic sulfonate product has a biodegradability of at least90%, as determined by ASTM D2667-95(2001). EXAMPLE - A hydrotreated composition of Fischer-Tropsch liquid was used as an input to an AEA Technologies process simulation software. The physical property data for the 1-14C monomethyl-branched isomers was derived using the simulation's property estimation utility with normal boiling points, densities and critical constants as inputs. The simulation included three sequential distillations. The first distillation tower was simulated at approximately 30 psia with 585degreesF reboiler temperature, 300degreesF condenser temperature and 60 theoretical stages. Feed was charged into the 24th stage from the bottom. In addition to predominantly 10-14C product being removed as the overhead and bottoms streams, respectively, a liquid sidestream was removed from stage 42. The simulation was run such that the overhead stream contained the majority of isomeric 14C and bottoms stream contained the majority of 14C branched isomers. The liquid sidestream was routed to a sidestripper for additional purification. After the sidestripper, 10-13C product was distilled in an isomeric distillation tower, operating at about 25 psia, 371degreesF condenser temperature and 463degreesF reboiler temperature. The tower was simulated with 75 stages, with feed introduced at stage 25 from the bottom and a stream containing approximately 30% n-decane and approximately 20% 11C n-paraffins was removed from the 65th stage. The overhead stream comprised primarily n-decane and the bottoms primarily of n-11C to n-13C. The bottoms were fed to the second tower. The second isomeric tower was also of 75 theoretical stages, with feed coming in at the 65th stage. The tower was simulated at 25 psia with 490degreesF reboiler temperature and 410degreesF condenser temperature. The overhead product was primarily n-11C. The bottoms product was n-12+C. The overhead products from both isomeric distillation towers and the bottoms product from the last isomeric distillation tower were combined as the high linearity product.