One way trip from Kansai airport to Fukuoka

I arrive at Kansai at 7am early March and have to get to Fukuoka to start touring around Kyushu island for 5 days before making my way back to Osaka (stopping at Hiroshima and Okayama)for my return flight?I will get the JR Sanyo pass for 7 days from Fukuoka to Osaka.
Please advise what is the best way to get to Fukuoka when I arrive in Kansai airport.
Thank you

I will get the JR Sanyo pass for 7 days from Fukuoka to Osaka.

The pass was discontinued in February 2015!

There is now the Sanyo Sanin Pass:
http://www.japan-guide.com/e/e2361_sanyo_sanin.html

The pass will be more expensive than regular shinkansen tickets unless you make some detours.

Please advise what is the best way to get to Fukuoka when I arrive in Kansai airport.

Your two best options are flying there or taking the shinkansen. Since you are already at Kansai Airport, I recommend flying:
http://www.japan-guide.com/e/e4802.html?aFROM=2157_2161

You don't say how you are touring. The rail passes mentioned above are only good up to Hakata Station. If you are going to travel by rail, then a JR Kyushu Rail Pass would fit your plans nicely. There is one type just for northern Kyushu and one for the whole island.
http://www.japan-guide.com/e/e2361_05.html
For a trip of just 5 days, I'd say sticking to northern Kyushu is probably more cost and time effective. There are many good place to see within the area - Fukuoka, Nagasaki, Beppu, and Kumamoto are just a few.
Nagasaki has the most variety and definitely worth a day and overnight. Mt Inasa has a mountaintop view over the city that is one of the best in Japan, plus there are numerous historical places to visit.
https://www.youtube.com/playlist?list=PL7LcPcmoSg-gbw2yXNLK92siHyNqSNx...
Fukuoka has a number of good places as well, including some of Japan's oldest temples, and even newer ones that are truly marvelous.
https://www.youtube.com/playlist?list=PL7LcPcmoSg-j4RLa6iC7ayvBAbOn8-0...
Beppu is famous for its hot springs as well as its Hells Tour, and nearby monkey park/aquarium.
https://www.youtube.com/playlist?list=PL7LcPcmoSg-hOggZamc2lUNTr46ApKX...
And Kumamoto has its castle, Suizenji Garden, and other sights that are worth it. Aso will probably be off limits still near the crater, but other areas are likely to be open.