Oil removal from water by sorption on hydrophobic cotton fibers. 2. Study of sorption properties in dynamic mode

The recovery of oil from an oil-in-water emulsion, during a flow through a bed of cotton rendered hydrophobic by acylation of cellulose was defined by sorption and coalescence phenomena. During percolation, the column hold-up (difference between injected and rejected oil) became constant at the equilibrium volume, i.e., as soon as the instant oil concentration in the effluent (C) was equal to the oil concentration in the initial emulsion (C-0). This equilibrium permitted the measurement of the cotton sorption capacity (SC), which increased with C-0 up to the cotton saturation. The oil-water separation improved at a lower temperature, lower flow, a deeper medium, and larger oil drops. The system was modeled as a piston flow-through in order to generalize the results.