Fast and efficient upgrading of levulinic acid into long-chain alkyl levulinate fuel additives with a tungsten salt catalyst at low temperature† Songyan Jia, *abd Jiao Ma,a Dongping Wang,a Kangjun Wang,*acd Qiang Zheng,a Chunshan Songb and Xinwen Guo b Author affiliations * Corresponding authors a College of Chemical Engineering, Shenyang University of Chemical Technology, Shenyang, Liaoning 110142, China E-mail: jiasongyan@126.com Tel: +86-24-89386342 b State Key Laboratory of Fine...