George, please be careful using "furfurol" or "furfural". In chemical sense this isn't the same: furfurOL is an alcohol and has an -OH hydroxyl group, while furfurAL is an aldehyde and has an -H atom attached to carbonyl group thus forming an -CHO group. If the details of the refining process described in your text are unknown, I would use "furfurol" just as it stands in Polish text:
"selective refinement with furfurol"

For your information:
nice PowerPoint presentations describing the differences between alcohols, ethers, aldehydes, ketones etc:
http://www.karentimberlake.com/alcohols,_ethers,_aldehydes,_...

Please also read the following passage:
...All of the revisions contained furfuraldehyde, termed furfurol in the FSU, in the composition and the solidification agent began to be
termed Conservant "Furfurol" (F) or simply Furfurol F as sort of a "trade name". Furfural based polymers (furans) have been used worldwide in the fabrication of polymer concrete pipes, as an organic cementing and sand consolidating material in oil wells, as floor coatings, and as chemically resistant containers. The basic
chemical in furans either furfuryl alcohol (furfurol) or furfuraldehyde (furfural) are inexpensive. Furfural can be obtained commercially from agricultural by-products such as corncobs, cottonseed hulls, oat hulls, etc. Furfurol is produced by catalytic
hydrogenation of the furfural.
http://www.dne.bnl.gov/~kalb/furf_pap.htm