Exhibit 99.2

                          CERTIFICATION PURSUANT TO
                           18 U.S.C. SECTION 1350,
                           AS ADOPTED PURSUANT TO
                SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


In connection with the Quarterly Report of Zoltek Companies, Inc. (the
"Company") on Form 10-Q for the period ending June 30, 2002 as filed with
the Securities and Exchange Commission on the date hereof (the "Report"), I,
James F. Whalen, Chief Financial Officer of the Company, certify, pursuant
to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, to the best of my knowledge and belief, that:

          (1)  The Report fully complies with the requirements of section
               13(a) or 15(d) of the Securities Exchange Act of 1934; and

          (2)  The information contained in the Report fairly presents, in
               all material respects, the financial condition and results of
               operations of the Company.


Date: August 14, 2002                      By:     /s/  James F. Whalen
      ---------------                         --------------------------------
                                                     James F. Whalen
                                                  Chief Financial Officer