Sulfur reservoir concentrations

The regeneration of a micromembrane suppressor occurs in much the same way as for a hollow fiber suppressor. The regenerent is delivered pneumatically from the reservoir, since the required flow rate cannot be obtained simply via gravity feed. While a sulfuric acid concentration of c = 0.01 mol/L suffices for isocratic operation, a twofold regenerent concentration is recommended for gradient techniques. The flow rate should be adjusted to ensure a sufficiently low background conductivity when the maximum eluent conentration is reached. Maintaining these conditions, one can then switch to the initial eluent concentration. 

After the SO converter has stabilized, the 6—7% SO gas stream can be further diluted with dry air, I, to provide the SO reaction gas at a prescribed concentration, ca 4 vol % for LAB sulfonation and ca 2.5% for alcohol ethoxylate sulfation. The molten sulfur is accurately measured and controlled by mass flow meters. The organic feedstock is also accurately controlled by mass flow meters and a variable speed-driven gear pump. The high velocity SO reaction gas and organic feedstock are introduced into the top of the sulfonation reactor,, in cocurrent downward flow where the reaction product and gas are separated in a cyclone separator, K, then pumped to a cooler, L, and circulated back into a quench cooling reservoir at the base of the reactor, unique to Chemithon concentric reactor systems. The gas stream from the cyclone separator, M, is sent to an electrostatic precipitator (ESP), N, which removes entrained acidic organics, and then sent to the packed tower, H, where SO2 and any SO traces are adsorbed in a dilute NaOH solution and finally vented, O. Even a 99% conversion of SO2 to SO contributes ca 500 ppm SO2 to the effluent gas. 

Quantitatively transfer the hydrolysis reaction solution to a 50-mL glass culture tube with a screw-cap by rinsing witli 3x5 mL of deionized water followed by 5 mL of 30% (v/v) sulfuric acid and one additional 5 mL of deionized water. Rinse the Teflon culture tube with acetone and transfer to the glass culture tube. Extract the acidic aqueous phase (pH 1) with 3 x 2.5 mL of toluene. Pass each upper toluene phase through approximately 3 g of anhydrous sodium sulfate contained in a 6-mL disposable filtration cartridge into a 10-mL volumetric flask. Adjust the volume of the solution to 10 mL with toluene. Condition a 3-mL diolsilane bonded silica gel SPE cartridge with two column volumes of toluene. Load a 5-mL aliquot of toluene solution and collect the eluate in a 125-mL round-bottom flask. Elute the column with an additional 50 mL of toluene (use the 75-mL reservoirs) and collect the eluate in the same round-bottom flask. Concentrate the toluene extract to approximately 3.0 mL at 40 °C under weak reduced pressure with a rotary evaporator. 

Steel objects, when exposed to humid atmospheres or when immersed in electrolytes, corrode at a rapid rate. For example, abrasively polished, cold-rolled steel panels will show signs of rust within 15 minutes when immersed in dilute chloride solutions with pH in the range of 7-10. One of the methods used to control this rapid corrosion is to coat the metal with a polymeric formulation such as a paint. The role of the paint is to serve primarily as a barrier to environmental constituents such as water, oxygen, sulfur dioxide, and ions and secondarily as a reservoir for corrosion inhibitors. Some formulations contain very high concentrations of metallic zinc or metallic aluminum such that the coating provides galvanic protection as well as barrier protection, but such formulations are not discussed in this paper. 

Sulfur compounds in the gas oil fractions from two bitumens (Athabasca oil sand and Cold Lake deposit)> a heavy oil (Lloydminster) from Cretaceous reservoirs along the western Canada sedimentary basin, and a Cretaceous oil from a deep reservoir that may be mature (Medicine River) are investigated. The gas oil distillates were separated to concentrates of different hydrocarbon types on a liquid adsorption chromatographic column. The aromatic hydrocarbon types with their associated sulfur compounds were resolved by gas chromatographic simulated distillation and then by gas solid chromatography. Some sulfur compounds were further characterized by mass spectrometry. The predominant sulfur compounds in these fractions are alkyl-substituted benzo- and dibenzothiophenes with short side chains which have few dominant isomers. 

Equations (4.1) through (4.18) are supplemented in each cell of the spatial division of the ocean surface with initial conditions (Table 4.3). The boundary conditions for Equations (4.11) through (4.18) are zero. The calculation procedure to estimate sulfur concentration consists of two stages. First, at each time moment th for all cells Qiy, Equations (4.1)-(4.18) are solved by the quasi-linearization method, and all reservoirs of sulfur are estimated for ti+x = tf + At, where time step At is chosen from the convergence state of the calculation procedure. Then, at moment t(+1 using the climate unit of the global model these estimates are specified with account of the atmospheric transport and ocean currents over time At. 

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