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                                                                   EXHIBIT 10.41


                   LOAN EXTENSION AND MODIFICATION AGREEMENT

         THIS LOAN EXTENSION AND MODIFICATION AGREEMENT (this "Agreement"), is
made as of _______________, 2002, by and among Probex Corp., a Delaware
corporation (the "Company"), and the lenders listed on Exhibit A hereto
(individually, a "Lender", and collectively, the "Lenders").

         WHEREAS, the Company has outstanding $3 million aggregate original
principal amount of those certain convertible promissory notes (individually, a
"Note", and collectively, the "Notes") made in favor of the Lenders;

         WHEREAS, the Lenders and the Company desire to further secure the
obligations under the Notes by entering into an Intercreditor and Security
Agreement (the "Security Agreement") in the form attached as Exhibit B hereto,
which grants the Lenders a security interest in the Collateral (as defined in
the Security Agreement);

         WHEREAS, in exchange for the additional security interest granted by
the Company to the Lenders, the Company and the Lenders desire to amend the
Notes to extend the maturity date of the Notes and amend certain provisions of
that certain Security Agreement, dated as of September 7, 2001 (the "Existing
Security Agreement"), to which the Company and the Lenders are currently
parties, either directly or as a result of being a holder of a Note.

         NOW THEREFORE, for valuable consideration, the receipt and adequacy of
which are hereby acknowledged, the Lenders and the Company hereby agree as
follow:

1.       AMENDMENT TO THE NOTES. Subject to the terms and conditions of this
Agreement, each Lender hereby agrees to extend the maturity date of their
respective Note until the earlier of (i) the Qualified Financing (hereinafter
defined) or (ii) February 28, 2003. Further, upon execution hereof, the Notes
shall be amended as follows:

         (a)      The second sentence of Section 1 of the Note shall be deleted
                  in its entirety and replaced with the following sentence:

         "This Note and all accrued and unpaid interest shall be due and payable
         in one lump sum on the earlier of: (i) the Qualified Financing
         (hereinafter defined) or (ii) February 28, 2003 (the "Maturity Date")."

         (b)      Section 3 of the Note shall be deleted in its entirety and
                  replaced with the following:

                  "3. Conversion. The outstanding principal balance and all
         accrued and unpaid interest due under this Note upon the consummation
         of the Qualified Financing, shall automatically be converted into
         fully-paid and non-assessable shares of Maker's preferred or common
         stock identical in all respects as to those shares issued to the
         purchasers in the Qualified Financing. The number of shares issued to
         Payee upon conversion of this Note shall be equal to the outstanding
         principal balance and all accrued and unpaid interest due under this
         Note on the date of the consummation of the Qualified Financing divided
         by the purchase price paid to Maker by such purchasers for each share
         of Maker's stock in the Qualified Financing. For purposes of this Note,
         "Qualified Financing" shall mean project financing, whether in the form
         of debt or equity securities of Maker, aggregating at least $30 million
         to be used to construct Maker's initial


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         reprocessing facility, excluding the outstanding principal balance and
         interest due under this Note on the date of consummation thereof."

         (c)      Section 4 of the Note shall be deleted in its entirety.

2.       ISSUANCE OF WARRANTS. The Company shall issue to each Lender, for no
additional cash consideration but as consideration for extending the maturity
date of the Lender's Notes as set forth in Section 1 hereof, a warrant (the
"Warrants") to purchase that number of shares of the Company's common stock
equal to the product of (i) principal amount of the Note and (ii) 0.35. The
Warrants shall have the exercise price, be for the term and otherwise be in
substantially the form attached as Exhibit C hereto.

3.       CONSENT TO LIEN; AMENDMENT TO SECURITY AGREEMENT. Pursuant to the
Existing Security Agreement, the Lenders hereby expressly consent to the
granting of the lien and security interest pursuant to, and the incurrence of
the indebtedness contemplated by, the Existing Security Agreement. Further, upon
execution hereof, the Existing Security Agreement shall be amended as follows:

         (a)      Section 3.18 of the Existing Security Agreement shall be
                  deleted in its entirety.

         (b)      The last sentence of Section 3.12 of the Existing Security
                  Agreement shall be deleted in its entirety.

         (c)      Section 3.19 of the Existing Security Agreement shall be
                  deleted in its entirety.

         (d)      Section 3.24 of the Existing Security Agreement shall be
                  deleted in its entirety.

4.       PENALTY SHARES. The issuance of shares of the Company's common stock
for each month that the principal amount and accrued and unpaid interest due and
payable under the Notes shall be terminated as of the date hereof, but effective
retroactively to December 31, 2001.

5.       BOARD REPRESENTATION. The Lenders and the holders of those certain
promissory notes of the Company, dated as of September 13, 2001 and from
February 20, 2001 to July 15, 2001 (as amend, modified, amended and restated,
from time to time, the "Bridge Notes"), shall be entitled to appoint one member
to the Company's board of directors until the Notes and the Bridge Notes are
paid in full. Pursuant to this section, the Lenders hereby appoint Ronald J.
Tiso as their representative on the board of directors. In the event of Mr.
Tiso's death, disability, removal or resignation, and if the Notes and the
Bridge Notes are then outstanding, the Lenders shall select another individual
to serve as such representative, such person to be selected by the vote of the
holders of a majority in principal amount of the Notes and Bridge Notes
outstanding on the date of such vote.

6.       MISCELLANEOUS.

         6.1 Amendments. Except as specifically amended herein, the Existing
Security Agreement and the Notes shall remain in full force and effect,
including, without limitation, their respective priority security interest.

         6.2 No Waiver; Cumulative Remedies. No failure on the part of the
Lenders or the Company to exercise and no delay in exercising, and no course of
dealing with respect to, any right, power, or privilege under this Agreement
shall operate as a waiver thereof, nor shall any

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single or partial exercise of any right, power, or privilege under this
Agreement preclude any further exercise thereof or the exercise of any other
right, power, or privilege. The rights and remedies provided for in this
Agreement are cumulative and not exclusive of any rights and remedies provided
by law.

         6.3 Successors and Assigns. This Agreement shall be binding upon and
inure to the benefit of the Lenders and the Company and their respective heirs,
personal representatives, successors and assigns, except that the Company may
not assign any of its rights or obligations under this Agreement without the
prior written consent of the Lenders.

         6.4 Amendment; Entire Agreement. THIS AGREEMENT, THE NOTES, THE
SECURITY AGREEMENT, THE REGISTRATION RIGHTS AGREEMENT, DATED AS OF SEPTEMBER 7,
2001, BY AND AMONG THE PARTIES THERETO AND THE EXISTING SECURITY AGREEMENTS,
INCLUDING THE EXHIBITS AND SCHEDULES ATTACHED HERETO AND THERETO, EMBODIES THE
FINAL, ENTIRE AGREEMENT AMONG THE PARTIES HERETO AND SUPERSEDES ANY AND ALL
PRIOR COMMITMENTS, AGREEMENTS, REPRESENTATIONS, AND UNDERSTANDINGS, WHETHER
WRITTEN OR ORAL, RELATING TO THE SUBJECT MATTER HEREOF AND MAY NOT BE
CONTRADICTED OR VARIED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OR DISCUSSIONS OF THE PARTIES HERETO. THERE ARE NO ORAL AGREEMENTS
AMONG THE PARTIES HERETO. The provisions of this Agreement may be amended or
waived only by an instrument in writing signed by the parties hereto.

         6.5 Governing Law; Severability. THIS AGREEMENT SHALL BE DEEMED A
CONTRACT MADE UNDER THE LAWS OF THE STATE OF NEW YORK AND ACCEPTED BY LENDER IN
SAID STATE, AND ANY AND ALL CLAIMS, DEMANDS OR ACTIONS IN ANY WAY RELATING
THERETO OR INVOLVING ANY DISPUTE BETWEEN ANY OF THE PARTIES TO THIS AGREEMENT,
WHETHER ARISING IN CONTRACT OR TORT, AT LAW, IN EQUITY OR STATUTORILY, SHALL BE
CONSTRUED AND ENFORCED IN ACCORDANCE WITH AND/OR GOVERNED BY THE LAWS OF THE
STATE OF NEW YORK (EXCEPTING ITS CHOICE OF LAW RULES, OTHER THAN SECTION 5-1401
OF NEW YORK'S GENERAL OBLIGATION LAW) AND THE LAWS OF THE UNITED STATES OF
AMERICA. If any provisions of this Agreement shall be invalid or unenforceable
to any extent, the remainder of this Agreement shall not be affected thereby and
shall be enforceable to the greatest extent permitted by law. Furthermore, in
lieu of such invalid or unenforceable provisions, there shall be added
automatically as part of this Agreement, a provision or provisions as similar in
its or their terms to such invalid or unenforceable provisions as may be
possible and be legal, valid and enforceable.

         6.6 Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same agreement.

         6.7 Headings. The headings, captions and arrangements used in this
Agreement are for convenience only and shall not affect the interpretation of
this Agreement.


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         IN WITNESS WHEREOF, the Company and the Lenders have caused this
Agreement to be duly executed as of the day and year first above written.

                                         COMPANY:

                                         PROBEX CORP.,
                                         a Delaware corporation

                                         By:
                                             -----------------------------------
                                         Name:  Bruce A. Hall
                                         Title: Senior Vice President



                                         LENDERS:

                                         UNITED INFRASTRUCTURE COMPANY, LLC,
                                         a Delaware limited liability company

                                         By:
                                            ------------------------------------
                                            Nora A. Blum
                                            Vice President



                                         THE LENDERS LISTED ON SCHEDULE A HERETO

                                         By:  Zesiger Capital Group, LLC
                                              As agent and attorney-in-fact

                                              By:
                                                 -------------------------------
                                              Name:
                                                   -----------------------------
                                              Title:
                                                    ----------------------------


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                                    EXHIBIT A

                            LENDERS FOR WHICH ZESIGER
                     IS ACTING AS AGENT AND ATTORNEY-IN-FACT

A. Carey Zesiger
The Jenifer Altman Foundation
Alexa L. Zesiger
Albert L. Zesiger
Asphalt Green, Inc.
Barrie Ramsay Zesiger
Butler Family LLC
David Zesiger
Francois DeMenil
Dean Witter Foundation
Gutierrez Anderson Community Trust UDT dated June 18, 2001
HBL Charitable Unitrust
Helen Hunt
Jeanne L. Morency
Psychology Associates
Leonard Kingsley
Lazar Foundation
Peter Looram
Mary C. Anderson Revocable Trust UDT dated July 6, 1999
Murray Capital, LLC
Meehan Foundation
The Meehan Investment Partnership I, L.P.
City of Milford Pension & Retirement Fund
Domenic J. Mizio
Morgan Trust Co. of the Bahamas Ltd. as Trustee U/A/D 11/30/93
NFIB Corporate Account
Nicola Z. Mullen
Public Employee Retirement System of Idaho
City of Stamford Firemen's Pension Fund
Susan Uris Halpern
Theeuwes Family Trust, Felix Theeuwes Trustee
William B. Lazar
Wells Family LLC
Wolfson Investment Partners LP


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                                    EXHIBIT B

                  FORM OF INTERCREDITOR AND SECURITY AGREEMENT


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                                    EXHIBIT C

                                 FORM OF WARRANT