Variety Trial and Pyrolysis Potential on Kenaf Grown in Iowa.

Kenaf (Hibiscus cannabinus L.) is a warm-season, herbaceous plant mostly used as a fiber-crop in the textile and pulp industry, but also has potential for lignocellulosic bioenergy. Midwest studies on growth and use of kenaf have been scant; however, kenaf may have potential as an alternative crop for Iowa and the Midwest. Seven kenaf varieties were grown in Boone County, IA between 2004 and 2007 and evaluated for their production potential in the Midwest.  More specifically, our questions were: 1) how do kenaf varieties perform in Iowa for yield?, 2) how does fiber morphology and quality differ among varieties and among core and bast fiber?, and 3) what potential does kenaf (bast and core) have for producing fuel using fast pyrolysis? The results show that Tainung 2 was the most productive variety in Central Iowa over multiple years. With regards to its chemical composition, bast kenaf had 8% more cellulose and 23% less hemicellulose than the core but it varied among varieties. Also, regardless of variety, core had in average more 40% lignin than bast. In general, core components were sensitive to climate conditions (year) whereas bast components were more affected by genetic variability for fiber composition. Similar to the plant morphology, the chemical composition determined by micro-pyrolysis showed that there are significant differences among varieties and between bast and core fiber. Overall, Tainung 2 would be the most promising cultivar for Central Iowa and could be grown to diversify Iowa agriculture and provide alternative feedstock to the biofuel industry.