I doubt if you would be able to clean it up.

in fact, the ratio of 260/280 is not a critical concern in library preparation. first you need to check if concentration of your DNA sample is too high (in which case you need to make a series dilution and test diluted sample), or too low. Most importantly you need to do an gel electrophoresis to confirm both effective DNA concentration and intactness of DNA, which plays  a more direct and critical  role in success sequencing