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                                                                     Exhibit 4.5

                            Stock Option Agreement
                            ----------------------
                                 CONFIDENTIAL

  This Stock Option Agreement (the "Agreement") made effective as of the 3rd day
of February, 1999, by and between Syntroleum Corporation, a Kansas corporation
("Syntroleum") and W. John Hutton ("Grantee"), evidences the grant by Syntroleum
of an option (the "Option") to Grantee to purchase shares of Syntroleum common
stock, par value $0.01 per share ("Common Stock"), pursuant to action of the
Board of Directors on February 3, 1999 (the "Date of Grant") and Grantee's
acceptance of the Option in accordance with the provisions of the Syntroleum
1993 Stock Option and Incentive Plan (the "Plan"). Syntroleum and Grantee agree
as follows.

  1.   Grant of Option and Exercise Price.  Syntroleum grants to Grantee the
       ----------------------------------
Option to purchase 8,000 shares of Common Stock at an exercise price of $6.88
per share, the Fair Market Value (as defined in the Plan) of Syntroleum Common
Stock on the Date of Grant, subject to the terms and conditions of this
Agreement and of the Plan, the provisions of which are incorporated into this
Agreement by this reference.  The shares subject to the Option are intended to
be Incentive Stock Option (ISO) shares as described in Section 422(b) of the
Internal Revenue Code of 1986, as amended.

  2.   Vesting.  Except as otherwise provided in Section 3 of this Agreement or
       -------                                   ---------
in the Plan, the Option shall vest as follows:  (a) the right to exercise the
Option and purchase 2,667 shares shall vest on the first annual anniversary of
the Date of Grant, (b) the right to exercise the Option and purchase 2,667
shares shall vest on the second annual anniversary of the Date of Grant, and (c)
the right to exercise the Option and purchase the remaining 2,666 shares shall
vest on the third annual anniversary of the Date of Grant.

  3.   Exercise Period.  The Option may be exercised from time to time with
       ---------------
respect to all or any number of the then vested, unexercised shares on any
regular business day of Syntroleum at its then executive offices, until the
earliest to occur of the following dates:  (a) the tenth anniversary of the Date
of Grant; (b) 12 months after the date of Grantee's termination of employment
with Syntroleum by reason of death or disability; (c) the third annual
anniversary of Grantee's retirement; or (d) the date 30 days following the date
upon which Grantee's employment with Syntroleum terminates for any reason other
than those described in subsections (b) or (c) of this Section 3.
                                                       ---------

  4.   Exercise.
       --------

  4.01 During the period that the Option is exercisable, it may be exercised in
full or in part by Grantee or, in the event or Grantee's death, by the person or
persons to whom the Option was transferred by will or the laws of decent and
distribution, by delivering or mailing written notice of the exercise to the
Secretary of Syntroleum.  The written notice shall be signed by each person
entitled to exercise the Option and shall specify the address and Social
Security number of each such person.  If any person other than Grantee purports
to be entitled to exercise all or any portion of the Option, the written notice
shall be accompanied by proof, satisfactory to Syntroleum, of that entitlement.

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                      Syntroleum - Stock Option Agreement
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                                 CONFIDENTIAL


  4.02  Subject to the provisions of Section 4.04 and 4.05, the written notice
                                     ------------     ----
shall be accompanied by full payment of the exercise price for the shares as to
which the Option is exercised either (i) in cash, (ii) in shares of Common Stock
evidenced by certificates either endorsed or with stock powers attached
transferring ownership to Syntroleum, with the aggregate Fair Market Value (as
defined in the Plan) equal to said exercise price on the date the written notice
is received by the Secretary, or (iii) in any combination of cash and such
shares.

  4.03  Notwithstanding the provisions of Section 4.02, shares acquired through
                                          ------------
the exercise of an ISO granted under the Plan may be used as payment at exercise
under this Agreement only if such shares have been held for at least 12 months
following such acquisition.

  4.04  In lieu of payment of the exercise price by way of delivery of
certificate(s) evidencing shares of Common Stock, Grantee may furnish a
notarized statement reciting the number of shares being purchased under the
Option and the number of Syntroleum shares owned by Grantee which may be freely
delivered as payment of all or a portion of the exercise price, all pursuant to
rules adopted by and subject to the consent of the Committee.  Subject to the
consent of the Committee, Grantee will be issued a certificate for new shares of
Common Stock representing the number of shares as to which the Option is
exercised, less the number of shares described in the notarized statement as
constituting payment under the Option.

  4.05  In the event Grantee pays the Option exercise price by delivery of a
notarized statement of ownership or by surrendering his right to exercise a
portion of the Option as described in Sections 4.04 and 4.05, the number of
                                      -------------     ----
shares remaining subject to the Option shall be reduced not only by the number
of new shares issued upon exercise of the Option but also by the number of
previously owned shares listed on the notarized statement of ownership and
deemed to be surrendered as payment of the exercise price or, as applicable, by
the number of shares in connection with which Grantee has surrendered his right
to exercise the Option.

  4.06  The written notice of exercise will be effective and the Option shall be
deemed exercised to the extent specified in the notice on the date that the
written notice (together with required payment of the exercise price) is
received by the Secretary of Syntroleum at its executive offices during regular
business hours.

  5.    Transfer of Shares; Tax Withholding. As soon as practicable after
        -----------------------------------
receipt of an effective written notice of exercise and full payment of the
exercise price as provided in Section 4 above, the Secretary of Syntroleum shall
                              ---------
cause ownership of the appropriate number of shares of Syntroleum Common Stock
to be issued to the person or persons exercising the Option by having a
certificate or certificates for such number of shares registered in the name of
such person or persons and shall have each certificate delivered to the
appropriate person. Each such certificate shall bear a legend describing, to the
extent applicable, (a) Syntroleum's right of first refusal, if any, in the event
such person desires or attempts to transfer such shares, and (b) the
restrictions imposed by applicable state and federal securities laws, as
described in Section 6.03. Notwithstanding the foregoing, if Syntroleum
             ------------
requires reimbursement of any tax required by law to be withheld with respect to
shares of Syntroleum Common Stock, the Secretary shall not transfer ownership of
shares until the required payment is made.

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                      Syntroleum - Stock Option Agreement
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                                 CONFIDENTIAL


  6.    Miscellaneous.
        -------------

  6.01  The rights under this Agreement may not be transferred except by will or
the laws of descent and distribution.  The rights under this Agreement may be
exercised during the lifetime of Grantee only by Grantee (or by his guardian or
legal representative).  The terms of the Option shall be binding upon the
executors, administrators, heirs, successors, and assigns of Grantee.

  6.02  Authorized leaves of absence from Syntroleum shall not constitute a
termination of employment for purposes of this Agreement.  For purposes of this
Agreement, an authorized leave of absence shall be an absence while Grantee is
on military leave, sick leave, or other bona fide leave of absence so long as
Grantee's right to employment with Syntroleum is guaranteed by statute,
contract, or company policy.

  6.03  The Option may not be exercised if the issuance of shares of
Syntroleum's Common Stock upon such exercise of the Option would constitute a
violation of any applicable federal or state securities or other law or
regulation.

  6.04  Grantee shall have no rights as a stockholder with respect to any shares
covered by the Option until the date of the actual issuance of the shares.  No
adjustment shall be made for dividends (ordinary or extraordinary, whether in
cash, securities or other property) or distributions or other rights for which
the record date is prior to the date the shares or any part thereof are issued
pursuant to exercise of all or any part of the Option.

  6.05  Grantee agrees not to disclose to any person, directly or indirectly,
the terms of this Agreement or any other matters relating to the Option or the
shares, including the number of shares subject to the Option or purchased
hereunder, without the prior consent of Syntroleum.

  6.06  The existence of the Option granted in this Agreement shall not affect
in any way the right or the power of Syntroleum or its stockholders to make or
authorize any or all adjustments, recapitalizations, reorganizations or other
changes in Syntroleum's capital structure or its business, or any merger or
consolidation of Syntroleum, or any issue of bonds, debentures, preferred or
prior preference stocks ahead of or affecting the Common Stock or the rights
thereof, or the dissolution or liquidation of Syntroleum or any sale or transfer
of all or any part of its assets or business, or any other corporate act or
preceding, whether of a similar character or otherwise.

  6.07  Every notice or other communication relating to this Agreement shall be
in writing and shall be mailed to or delivered to the party for whom it is
intended at such address as may from time to time be designated by it in a
notice mailed or delivered to the other party as herein provided, however, that
unless and until some other address be so designated, all notices or
communications by Grantee to Syntroleum shall be mailed or delivered to
Syntroleum at the offices of its Secretary at Suite 1100, 1350 S. Boulder,
Tulsa, Oklahoma 74119, and all notice or communications by Syntroleum to Grantee
may be given to Grantee personally or may be mailed to him.

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                      Syntroleum - Stock Option Agreement
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                                 CONFIDENTIAL


  6.08  The validity and effect of this Agreement and the rights and obligations
of the parties, and all other persons affected by this Agreement shall be
construed and determined in accordance with the laws of the State of Oklahoma.

  IN WITNESS WHEREOF, Syntroleum, by its duly authorized officer, and Grantee
have signed this Agreement as of the date first above written.


                                    COMPANY:

                                    SYNTROLEUM CORPORATION


                                By: /s/ MARK A. AGEE
                                    ____________________________
                                    Mark A. Agee, President

                                    Syntroleum Corporation.
                                    1350 S. Boulder, Ste. 1100
                                    Tulsa, Oklahoma 74119


                                    GRANTEE:


                                    /s/ W. JOHN HUTTON
                                    ____________________________
                                    W. John Hutton

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