Evaluation of Carex Peat, Sphagnum Moss Peat, and Sphagnum Top Moss As Oil Sorbents

Abstract

Experiments were conducted to evaluate the ability of Carex peat, Sphagnum moss peat, and Sphagnum top moss to sorb (i.e., to take up and hold oil by either adsorption or absorption) Lloydminster and UHC crude oils. Pure component and mixed components of the peats and top moss were used. Experiments were carried out under ambient temperature and pressure. The sorptive capacity, sorptive rate, and height of capillary rise of oil was measured for the sorbents. The sorptive capacity of the pure Sphagnum top moss, for both oils, was significantly higher than that of the two peats. Mixtures of Sphagnum top moss and Sphagnum moss peat also had relatively high sorptive capacities. Carex peat and mixtures containing predominantly Carex peat had low sorptive capacities. The sorptive rates differed by both the oil type and sorbent. All pure component and mixed component sorbents had relatively low sorptive rates for the higher viscosity Lloydminster oil, and only slightly higher sorptive rates for the lower viscosity UHC crude oil. Mixing lower sorptive rate materials with higher sorptive rate materials resulted in lower than expected sorptive rates. In all cases, the height of capillary rise was found to be significantly higher for the mixed component sorbents than for the pure component sorbents. A preliminary cost-benefit assessment suggests that pure Sphagnum top moss, and mixtures that contain predominantly Sphagnum top moss are relatively inexpensive (0.022 to 0.031 US$/Kg oil sorbed) sorbents, and they may be competitive with common commercial oil sorbents.