PEER-REVIEWED ARTICLE bioresources.com Wong et al. (2016). “Oil absorption in plant fibers,” BioResources 11(3), 6452-6463. 6452 Impact of Fiber Treatment on the Oil Absorption Characteristics of Plant Fibers Chris Wong, a Tyler McGowan, a Sreekala G. Bajwa, b and Dilpreet S. Bajwa c, * Most plant fibers are good sorbents of oil; however, synthetic sorbents have a much higher sorption capacity (SC) than plant fibers. This study evaluated the effect of fiber treatments, specifically hot-water treatment and mercerization, on the absorption characteristics of selected plant fibers. Five common plant fibers—corn residues, soybean residues, cotton burr and stem (CBS), cattail, and oak—were evaluated for their absorption characteristics in crude oil, motor oil, deionized (DO) water, and a 80:20 mix of DO water. The fiber treatments included ground fiber (control), hot- water treatment at 80 °C for 4 h and 125 °C for 4 h, mercerization at room temp for 48 h, and mercerization at 300 °C for 1 h. The absorption capacity (AC) varied with fiber type, absorption medium, and fiber treatment. Mercerization at 300 °C increased the water absorption of soybean residue up to 8 g/g. Mercerization at room temperature and the hot-water treatment at 125 °C increased the crude oil absorption capacity. After certain treatments, the crude oil absorption capacity of CBS and corn fibers increased over 5 g/g, and the motor oil absorption capacity of cattail, corn, and soybean also increased to 4 to 5 g/g. Keywords: Plant fiber; Mercerization; Hot water treatment; Absorption; Oil; Water Contact information: a: Prairie View A&M University, Prairie View, TX, USA; b: Department of Biological & Agricultural Engineering and c: Department of Mechanical Engineering, North Dakota State University, Fargo, ND, USA; *Corresponding author: Dilpreet.bajwa@ndsu.edu INTRODUCTION The agricultural industry is a major consumer of lignocellulosic residues that are available for use in value-added products. The global production of agricultural residues from wheat straw, corn straw, rice straw, and sugarcane bagasse is estimated at 1.4 billion tons (Saini et al. 2015). In the U.S., approximately 244 million dry tons of agricultural biomass residues and wastes are available for bioenergy and byproduct applications every year (DOE 2011). There is a vast potential for developing new products and applications for these agricultural residues. Lignocellulosic fibers are good sorbents of oil, and the application of plant fibers as sorbent materials has great potential. In the last decade, there have been many major oil spills that have resulted in considerable environmental damage despite clean-up efforts. The recent incidents of shale oil spills from the Bakken formation of North Dakota have created many problems for oil clean-up (Inforum 2015). Currently, materials such as absorbents, dispersants, solidifiers, booms, and skimmers are being used for oil spill remediation (Nguyen et al. 2013). Absorbents function by completely absorbing the oil, thereby facilitating its removal from the medium (typically water) or spill area. In contrast, dispersants break down oil into smaller particles for its subsequent removal. The most commonly used absorbents include polypropylene, polyethylene, and polyurethane foams, although cellulosic materials and other natural materials, such as minerals, are also good sorbents (Deschamps et al. 2003;