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                                                                 EXHIBIT 10.22.4


                               SECURITY AGREEMENT

         This Security Agreement dated as of November 29, 2000 ("Security
Agreement") is between Probex Fluids Recovery, Inc., a Delaware corporation
("Debtor"), and Wilmington Trust Company ("Collateral Agent") for the benefit of
the Noteholders (the Collateral Agent and the Noteholders are hereinafter
sometimes referred to collectively as "Secured Party").


                                  INTRODUCTION

         A. The Debtor has entered into a Note Purchase Agreement of even date
herewith (as the same may be amended, modified, supplemented or restated from
time to time the "Note Purchase Agreement") with the noteholders party thereto
(together with their successors and assigns and any holder of the 7% Senior
Secured Convertible Notes, due November 28, 2004, issued thereunder (the
"Notes"), collectively referred to herein as the "Noteholders").

         B. Probex Corp., a Delaware corporation (the "Guarantor"), has entered
into a Guaranty Agreement of even date herewith (such document, as amended,
modified, supplemented or restated from time to time, collectively referred to
as the "Guaranty Agreement"), pursuant to which the Guarantor guaranteed the
debt of the Debtor owing to the Noteholders under the Note Purchase Agreement.

         C. The Debtor, the Noteholders, the Guarantor, and the Collateral
Agent, as collateral agent, have entered into an Intercreditor and Collateral
Agency Agreement of even date herewith (the "Intercreditor Agreement") (1) to
establish the relative rights of the Noteholders with respect to payment of
their respective obligations owed by the Debtor and the Guarantor, (2) to agree
as to the exercise of certain remedies with respect to the Collateral (as
defined in the Intercreditor Agreement), (3) to appoint Wilmington Trust Company
as collateral agent for the benefit of the Noteholders for the purposes of
administering the Collateral Documents (as defined in the Intercreditor
Agreement) and apportioning payments among the Noteholders, and (4) for other
purposes as set forth therein.

         D. It is a condition precedent to the effectiveness of the Note
Purchase Agreement that the Debtor shall secure its obligations under the Note
Purchase Agreement, the Collateral Documents and any other Financing Document
(in each case, as such terms are defined in the Intercreditor Agreement) by
entering into this Security Agreement.

         Therefore, the Debtor hereby agrees with the Collateral Agent on behalf
of and for the benefit of the Noteholders as follows:



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SECTION 1. Definitions. Any terms used in this Security Agreement that are
defined in the Uniform Commercial Code as in effect in the State of Texas
("UCC") shall have the meanings assigned to those terms by the UCC, whether
specified elsewhere in this Security Agreement or not.

SECTION 2. Security Interest.

         2.1. Grant of Security Interest. The Debtor hereby grants to the
Secured Party on behalf of and for the ratable benefit of the Noteholders a
first priority security interest in the Collateral (as defined in Section 2.2
below) to secure the performance and payment of (a) all obligations and amounts
due and payable by the Debtor now and hereafter existing under the Note Purchase
Agreement, the Notes, this Security Agreement, the other Collateral Documents
and any other Financing Documents (as defined in the Intercreditor Agreement),
whether for principal, interest, premiums, fees, expenses, indemnifications or
otherwise (all such obligations being collectively referred to herein as the
"Secured Obligations").

         2.2. Collateral. "Collateral" shall mean all of the Debtor' right,
title, and interest in the following, whether now owned or hereafter created or
acquired or arising:

                  (a) Accounts. All accounts whether now existing or hereafter
arising, and however evidenced or acquired, in which the Debtor now has or
hereafter acquire any rights (the term "Accounts" means and includes accounts,
accounts receivable, contract rights, including without limitation rights under
contracts for the purchase of supplies (in any such case to the extent a
security interest can be granted in particular contracts), instruments, notes,
drafts, acceptances, documents, chattel paper, any right of the Debtor to
payment for goods sold or leased for services rendered, whether arising out of
the sale of Inventory (as hereinafter defined) or otherwise and whether or not
earned by performance, and all other forms of obligations owing to the Debtor,
and all of the Debtor' rights to any merchandise (including without limitation
any returned or repossessed goods and the right of stoppage in transit) which is
represented by, arises from or is related to any of the foregoing);

                  (b) General Intangibles. All general intangibles, whether now
owned or hereafter acquired or arising, or in which the Debtor now has or
hereafter acquires any rights, including without limitation all causes of
action, goodwill and similar intangibles and all income tax refunds, all
privileges, franchises, immunities, licenses (to the extent a security interest
can be granted in particular licenses), permits and similar intangibles, any
rights to receive any payments in connection with the termination of any pension
plan or employee stock ownership plan or trust established for the benefit of
employees of the Debtor and all other intangible personal property (including
things in action) not otherwise covered by this Security Agreement;

                  (c) Inventory. All inventory, whether now owned or hereafter
acquired, and all documents of title at any time evidencing or representing any
part thereof (the term "Inventory" means and includes all goods (i) which are
held for sale or lease or are to be furnished under contracts of service or
consumed in the Debtor'



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business, or (ii) which are raw materials, work-in-progress, finished goods
(including, without limitation, supplies and related products), packaging
materials and all other materials and supplies of every nature in each case used
or usable in connection with the acquisition, manufacture, processing, supply,
servicing, storing, packing, shipping, advertising, selling, leasing or
furnishing of such goods and any constituents or parts thereof, or (iii) which
are returned or repossessed goods);

                  (d) Equipment. All equipment (as defined in Article 9 of the
UCC) wherever located, machinery, furniture, fixtures and motor vehicles, and
all parts thereof and all accessions and additions thereto (all such equipment
being the "Equipment");

                  (e) Intellectual Property. All patent applications, patents,
patentable inventions, whether or not reduced to practice, trademark
applications, trademarks, trade names, company names, business names, fictitious
names, service marks, tradestyles, logos, internet domain names or other source
or business identifiers, copyright applications, copyrights, all works of
authorship, designs, trade secrets, confidential or proprietary information,
know-how, processes, technique, research or development information, technical,
financial or customer information and any information which gives the Debtor a
commercial advantage, all licenses or agreements, whether written or oral,
granting to or by the Debtor any right of a type described herein, all
registrations and recordings thereof, including without limitation, goodwill of
the business connected with the use of or symbolized by any of the above,
registrations, recordings and applications in the United States Patent and
Trademark Office, United States Register of Copyrights or in any similar office
of agency of the United States, any State thereof or any county or any political
subdivision thereof, including, without limitation, those listed in Schedule
2.2(e) hereto (as the same may be amended from time to time), including without
limitation all renewals, reissues, divisions, continuations,
continuations-in-part, extensions, improvements, all copyrights of works based
on, incorporation in, derived from works covered by such copyrights or works of
authorship, all derivative works based on such copyrights or works of
authorship, the right to print, publish, distribute, derive and modify any of
the same thereof, all proceeds thereof including without limitation all
payments, license royalties and proceeds of infringement suits, and rights to
sue for past, present and future infringements and misappropriations and all
other rights of any kind whatsoever of the Debtor pertaining thereto or accruing
thereon, and all rights corresponding thereto throughout the world (all of the
foregoing being referred to collectively as the "Intellectual Property");

                  (f) Documents and Instruments. All documents and instruments
(each as defined in the UCC);

                  (g) Litigation Proceeds. All proceeds received by the Debtor
or to which the Debtor has any right which proceeds represent an award of
damages or a settlement from or in connection with any lawsuit brought by the
Debtor (or in which the Debtor participated) against any Person;

                  (h) Other. All other property or interests in property of any
type whatsoever in the possession of the Debtor to the extent such property is
not covered by



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the foregoing and to the extent a security interest may legally be granted in
such property or interests in property under the Uniform Commercial Code, it
being the intent of the Debtor to grant to the Secured Party a security interest
in all of the Debtor' property or interest in property, whether now owned or
hereafter acquired;

                  (i) Records. All supporting evidence and documents relating to
any of the above described property, including, without limitation, written
applications, credit information, account cards, payment records,
correspondence, delivery and installation certificates, invoice copies, delivery
receipts, notes and other evidences of indebtedness, insurance certificates and
the like, customer lists, together with all books of account, ledgers and
cabinets in which the same are reflected or maintained, all whether now existing
or hereafter arising (collectively, the "Records");

                  (j) Additions. All additions to and substitution and
replacement of any and of the foregoing, whether now existing or hereafter
arising; and

                  (k) Proceeds and Products. All proceeds and products of the
foregoing and all insurance of the foregoing and the proceeds thereof including,
without limitation, the proceeds of any business interruption insurance or any
key man life insurance policy covering the life of any officer or director of
the Debtor, whether now existing or hereafter arising.

SECTION 3. Representations and Warranties. The Debtor hereby represents and
warrants the following to the Secured Party and the Noteholders:

         3.1. The Debtor' Name Existence, Power, Authorization.

                  (a) The true and correct name of Debtor as listed on its
articles or certificate of incorporation, as applicable, is the name of Debtor
as listed on the signature pages to this Security Agreement. Debtor does not do
business and has not done business during the past five years under any trade
name or fictitious business name except as disclosed on Schedule 3.1;

                  (b) Debtor is a duly incorporated and existing corporation in
good standing under the laws of its jurisdiction of incorporation; and

                  (c) Debtor has all necessary corporate power and authority to
execute, deliver, enter into and carry out the terms of this Security Agreement.

         3.2. Inventory. All of the Inventory owned by Debtor is located at the
facilities specified on the attached Schedule 3.2. No Persons other than the
Debtor has possession of any of the Collateral. No negotiable document has been
issued to represent any Inventory.

         3.3. Accounts. The chief place of business and chief executive office
of Debtor and the office where Debtor keeps the Records are located at the
address set forth in the attached Schedule 3.3. None of the Accounts are
evidenced by a promissory note or other instrument that has not been pledged to
the Secured Party. To the best of



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Debtor's knowledge each Account constitutes the legally valid and binding
obligation of the customer obligated to pay the same arising from the sale,
lease or rendition by Debtor of goods or services. The amount represented by
Debtor to the Secured Party as owing by each customer is the correct amount
actually and unconditionally owing as of the date hereof.

         3.4. Equipment. All of the Equipment owned by Debtor is located at the
facilities specified on the attached Schedule 3.4. The Equipment is in good
working order to the extent necessary for the operation of Debtor's business.

         3.5. Intellectual Property. The Intellectual Property is subsisting and
has not been adjudged invalid or unenforceable. To the best of Debtor's
knowledge, all of the Intellectual Property is valid and enforceable. As of the
date hereof, no claim has been made that the use of any of the Intellectual
Property does or may violate the rights of any third person. Debtor has
generally used proper statutory notice in connection with its use of the
Intellectual Property and consistent standards of quality in its manufacture of
products sold under the Intellectual Property. Except as set forth on Schedule
2.2(e) hereto, no Debtor has granted any licenses, orally or in writing, which
are not terminable at will by such Debtor or which are not listed on Schedule
2.2(e). Debtor authorizes and requests that all applicable governmental offices,
including, without limitation, the Register of Copyrights, Commission of Patents
of Canada and Register of Trademarks of Canada record this document. Each of the
Debtor's material copyright rights has been identified to Secured Party and has
been registered at the United States Copyright Office.

         3.6. Other Liens. Debtor is the record and beneficial owner of all of
the Collateral free and clear of any Lien, except for the security interests
created by this Security Agreement and other Liens permitted by the Note
Purchase Agreement. No effective financing statement or other instrument similar
in effect covering all or any part of the Collateral is on file in any recording
office, except such as may have been filed in connection with (a) Liens created
by this Security Agreement or (b) other Liens permitted by the Note Purchase
Agreement.

         3.7. Lien Priority and Perfection. The security interest in the
Collateral created pursuant to this Security Agreement creates a valid, binding,
and first priority security interest in the Collateral, securing the payment,
performance and observance of the Secured Obligations, and such security
interests will be perfected first priority security interests upon the filing of
appropriate financing statements naming Debtor as debtor and Secured Party as
secured party in the jurisdictions set forth on the attached Schedule 3.7, in
each case only to the extent such interest may be perfected by the filing of a
financing statement under the UCC.

         3.8. Authorizations and Approvals. No other authorization, approval, or
other action by, and no notice to or filing with, any Governmental Authority is
necessary to grant the security interests contemplated hereby, or to allow
Debtor to perform (other than authorizations, approvals or actions required in
the performance of its business generally and which it expects to obtain in the
ordinary course of its business) its



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obligations hereunder, or to permit the Secured Party or any Noteholder to
exercise its rights and remedies hereunder.

         3.9. Accurate Information. All information supplied to the Secured
Party or any Noteholder by or on behalf of the Debtor with respect to the
Collateral is accurate and complete in all material respects as of the date
hereof.

SECTION 4. Debtor' Covenants.

         4.1. Further Assurances. Debtor agrees that at any time, at such
Debtor's expense, such Debtor shall promptly execute and deliver all further
instruments and documents and take all further action that may be necessary and
that the Secured Party or any Noteholder may reasonably request in order to
perfect and protect any security interest granted or purported to be granted
hereby or to enable the Secured Party or any Noteholder to exercise and enforce
its rights and remedies hereunder with respect to any Collateral. Without
limiting the generality of the foregoing, Debtor will, at the Secured Party's
request, (a) deliver and pledge to the Secured Party, duly indorsed or
accompanied by duly executed instruments of transfer or assignment, all in form
and substance satisfactory to the Secured Party, any instrument, document or
chattel paper representing any Account or arising as a result of the disposition
of any Collateral, and (b) execute and file such financing or continuation
statements, or amendments thereto, and such other instruments or notices as may
be reasonably necessary, and as the Secured Party may reasonably request, in
order to perfect and preserve the security interests granted or purported to be
granted hereby. Debtor shall furnish to the Secured Party from time to time any
statements and schedules further identifying and describing the Collateral and
such other reports in connection with the Collateral as the Secured Party may
reasonably request.

         4.2. Accounts and Inventory. Debtor shall use its commercially
reasonable efforts to collect payments on the Accounts when due. Debtor shall
perform its obligations under each contract related to or giving rise to any
Account. Except for Inventory in transit in the ordinary course of business,
Debtor shall keep all of the Inventory at the locations listed on Schedule 3.2.
Debtor shall not permit any negotiable document to represent any Inventory.
Debtor shall maintain and protect the Inventory and promptly furnish to the
Secured Party a statement regarding any material loss or damage to the
Inventory.

         4.3. Equipment. Debtor shall cause the Equipment to be maintained and
preserved in good working order, ordinary wear and tear excepted, and shall make
or cause to be made all repairs, replacements, and other improvements which in
each case are necessary or desirable to maintain the Equipment in good working
order for the needs of Debtor's business.

         4.4. Intellectual Property.

         (a) Debtor shall annually provide an accurate update of Schedule 2.2(e)
to the Secured Party, and, if any additional Intellectual Property is listed,
sign any



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documents reasonably requested by the Secured Party to fully perfect the Secured
Party's security interest in such additionally listed Intellectual Property and,
if any previously listed Intellectual Property is not listed on the annual
update to Schedule 2.2(e) or is listed with information that materially and
adversely affects its value, such Debtor shall provide the reasons why such
Intellectual Property is no longer listed or the reasons for such diminishment
of value (as applicable).

                  (b) Debtor shall use proper statutory notice in connection
with its use of the Intellectual Property and consistent standards of quality in
its manufacture of products sold under the Intellectual Property.

                  (c) No Debtor shall take any action, or permit any action to
be taken by others, including licensees, or fail to take any action or permit
any other to fail to take any action which would materially and adversely affect
the Intellectual Property.

                  (d) Whenever any of the Intellectual Property is used by or on
behalf of Debtor in a country where affixing a trademark notice is mandatory,
such Debtor shall affix or cause to be affixed a notice that the mark is a
trademark, a service mark or is registered, which notice shall be in a form
accepted or required by the trademark marking laws of such country in which the
mark is so used.

                  (e) Debtor shall promptly notify the Secured Party, in
writing, of any suit, action or proceeding brought against such Debtor relating
to, concerned with or affecting the Intellectual Property and shall, on request,
deliver to the Secured Party a copy of all pleadings, papers, order or decrees
theretofore and thereafter filed in any such suit.

                  (f) If requested by Secured Party, Debtor will identify its
unregistered copyrightable works to Secured Party and if requested by Secured
Party, file United States copyright applications for the works identified by
Secured Party for registration. Debtor shall use commercially reasonable efforts
to protect its trade secrets proprietary information and the like from
unauthorized use or disclosure.

                  (g) Debtor shall have the duty, if commercially reasonable, to
prosecute diligently any trademark applications with respect to the Intellectual
Property pending as of the date of this Security Agreement or thereafter to make
federal application on registrable but unregistered Intellectual Property if
requested by Secured Party, to file and prosecute opposition and cancellation
proceedings, to diligently maintain a suit to stop any infringement or any other
suit, action or proceedings brought against such Debtor relating to, concerned
with or affecting the Intellectual Property and to do any and all acts which are
necessary or desirable to preserve and maintain all rights in the Intellectual
Property. Upon request, such Debtor shall provide the Secured Party with a
complete status report of all Intellectual Property and upon request by the
Secured Party, such Debtor shall deliver to Secured Party, copies of any such
Intellectual Property and other documents concerned with or related to the
prosecution, protection, maintenance, enforcement and issuance of the
Intellectual Property.



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                  (h) Debtor agrees that it will not enter into any agreement
(including any license agreement) which is inconsistent with such Debtor's
obligations under this Security Agreement without the Secured Party's prior
written consent.

                  (i) Until the occurrence and continuance of an Event of
Default under the Note Purchase Agreement (collectively, an "Event of Default"),
the Secured Party hereby grants to Debtor the exclusive, nontransferable right
and license to use the Intellectual Property on and in connection with products
sold by the Debtor, for Debtor's own benefit and account and for none other.
Except as permitted in the Note Purchase Agreement, Debtor agrees not to sell or
assign its interest in, or grant any sublicense under, the license granted to
such Debtor hereunder, without the prior written consent of the Secured Party.

                  (j) Debtor shall not abandon any Intellectual Property without
the written consent of the Secured Party.

         4.5. Insurance.

                  (a) Policies and Certificates. Debtor shall, at its own
expense, maintain, or cause to be maintained, insurance with respect to the
Inventory and Equipment of such Debtor in such amounts, against such risks, in
such form, and with such insurers, as the Note Purchase Agreement requires. In
addition, upon request by the Secured Party, such Debtor shall deliver
certificates evidencing renewal of such insurance and evidence that the premiums
have been paid before termination of any insurance policies representing such
insurance. Upon request, Debtor shall deliver certificates evidencing such
insurance and copies of the underlying policies as they are available. If such
insurance is not maintained in full force and effect, the Secured Party at its
option may procure such insurance at such Debtor's expense. All policies
representing property insurance shall name the Secured Party as an additional
loss payee in a form satisfactory to the Secured Party. All policies
representing liability insurance shall name the Secured Party and the other
Noteholders, as additional named insured parties in a form satisfactory to the
Secured Party.

                  (b) Notice of Casualty Events, Etc. Immediately upon obtaining
knowledge thereof, Debtor shall notify the Secured Party of any material
casualty to the Collateral, including all casualties to the Collateral where the
aggregate damage to the Collateral would reasonably be expected to exceed
$1,000,000. With respect to any potential claims under any property insurance
maintained by such Debtor in excess of such amount, after the occurrence and
during the continuance of an Event of Default, the Secured Party shall make
proof of loss under, settle and adjust any claims under, and receive the
proceeds under any such property insurance or direct the Debtor to take such
actions at the direction of the Secured Party, and the expenses incurred by the
Secured Party in the adjustment and collection of such proceeds shall be paid by
the Debtor. The Secured Party shall not be liable or responsible for failure to
collect or exercise diligence in the collection of any proceeds.



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                  (c) Payments. With respect to any casualty to the Collateral,
after the occurrence and during the continuance of an Event of Default, all
proceeds of such casualty, including any property insurance proceeds, proceeds
from actions, and any other proceeds, whether or not above the amounts specified
above, are assigned to the Secured Party and shall be paid directly to the
Secured Party and applied in accordance with paragraph (d) below. In the event
that any such proceeds are paid to Debtor in violation of the foregoing, such
Debtor shall hold the proceeds in trust for the Secured Party, segregate the
proceeds from the other funds of such Debtor, and promptly pay the proceeds to
the Secured Party with any necessary endorsement. Upon the request of the
Secured Party, after the occurrence and during the continuance of an Event of
Default, Debtor shall execute and deliver to the Secured Party any additional
assignments and other documents as may be necessary or desirable to enable the
Secured Party to directly collect the proceeds.

                  (d) Application of Proceeds. With respect to the proceeds of
any casualty required to be paid to the Secured Party hereunder, after the
occurrence and during the continuance of an Event of Default, the Secured Party
may, subject to the terms of the Intercreditor Agreement, either retain the
proceeds and apply such proceeds as provided for in Section 5.7 or may disburse
the proceeds to the Debtor for the purpose of repairing, replacing, and
restoring the damaged Collateral.

         4.6. Transfer of Collateral; Release of Security Interest. Debtor shall
not sell, assign (by operation of law or otherwise), or otherwise dispose of any
of the Collateral (other than Inventory sold in the normal course of business),
except as permitted by the Note Purchase Agreement. The Secured Party shall
promptly, at the relevant Debtor's expense, execute and deliver all further
instruments and documents, and take all further action that such Debtor may
reasonably request in order to release its security interest in any Collateral
which is disposed of in accordance with the terms of the Note Purchase
Agreement.

         4.7. Change of Name. Debtor shall notify the Secured Party in writing
15 days prior to (a) any new location of any Property comprising a part of the
Collateral in which such Debtor is granting a security interest to the Secured
Party under the terms of this Security Agreement, or (b) any change in the
Debtor's name, identity or corporate structure, location of its chief executive
office, chief place of business or office where such Debtor keeps its records
concerning the Collateral.

         4.8. Defaults. Debtor shall notify Secured Party if there exists an
Event of Default (as defined herein).

         4.9. Claims. Debtor shall promptly notify the Secured Party of the
existence of any material claims, liens, security interests, rights or other
encumbrances with respect to any of the Collateral.

         4.10. Material Adverse Effect. Debtor shall promptly notify the Secured
Party in the event of any change in the nature or value of the Collateral which
could result in a



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Material Adverse Effect or which change could materially and adversely affect
the security interest of the Collateral Agent in the Collateral.

         4.11. Expenses. Debtor shall promptly pay all expenses incurred in
connection with the maintenance, preservation or other handling of the
Collateral and all taxes which are or may become a lien on the Collateral
promptly when due, unless such expenses, taxes or liens are being contested in
good faith by appropriate proceedings and no proceeding to enforce any tax liens
against the Collateral has begun, and in any event reimburse the Secured Party
for any expenses which it might incur in satisfying such expenses, liens or
taxes, which the Secured Party may reasonably incur, in its sole discretion, to
protect the Collateral.

SECTION 5. Events of Default. Any of the following events shall be an Event of
Default:

                  (a) the occurrence of any "Event of Default" as defined in the
Note Purchase Agreement;

                  (b) the failure of Debtor to pay any obligation due and
payable pursuant to the terms of this Security Agreement within three Business
Days after such payment is due; or

                  (c) the failure of Debtor to perform or observe any term or
provision of this Security Agreement, and such failure shall continue unremedied
for a period of 30 days after the earlier of (i) such Event of Default first
becomes known to any officer of Debtor or (ii) notice to Debtor by the Secured
Party of the occurrence of such Event of Default.

SECTION 6. Remedies. If any Event of Default shall have occurred and remain
uncured, and subject at all times to the terms of the Intercreditor Agreement:

         6.1. UCC Remedies. To the extent permitted by law, the Secured Party
may exercise in respect of the Collateral, in addition to other rights and
remedies provided for in this Security Agreement or otherwise available to it,
all the rights and remedies of a secured party under the UCC (whether or not the
UCC applies to the affected Collateral).

         6.2. Assembly of Collateral. The Secured Party may require Debtor to,
at such Debtor's expense, promptly assemble all or part of the Collateral and
make it available to the Secured Party at a place to be designated by the
Secured Party. The Secured Party may occupy any premises owned or leased by
Debtor where the Collateral or any part thereof is assembled for a reasonable
period in order to effectuate its rights and remedies hereunder or under law,
without obligation to such Debtor in respect of such occupation. The Secured
Party shall have no obligation to take any action to assemble or otherwise take
control of the Collateral, whether for the purposes of sale or otherwise.

         6.3. Sale of Collateral. Upon at least ten Business Days prior written
notice to the Debtor of the time and place of any proposed sale or other
disposition, the Secured Party may sell all or part of the Collateral at a
public or private sale, at any of the Secured



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Party's offices or elsewhere, for cash, on credit, or for future delivery, and
upon such other terms as is commercially reasonable. The Secured Party shall not
be obligated to make any sale of Collateral regardless of notice of sale having
been given. The Secured Party may adjourn any public or private sale from
time-to-time by announcement at the time and place fixed therefor, and such sale
may, without further notice, be made at the time and place to which it was so
adjourned.

         6.4. Accounts. The Secured Party may, or may direct Debtor to, take any
action the Secured Party deems necessary or advisable to enforce collection of
the Accounts including, without limitation, notifying the account Debtor or
obligors under any Accounts of the assignment of such Accounts to the Secured
Party and directing such account Debtor or obligors to make payment of all
amounts due or to become due directly to the Secured Party. Upon such
notification and direction, and at the expense of the Debtor, the Secured Party
may enforce collection of any such Accounts, and adjust, settle, or compromise
the amount or payment thereof in the same manner and to the same extent as the
Debtor might have done. After receipt by Debtor of the notice referred to above,
all amounts and proceeds (including instruments) received by such Debtor in
respect of the Accounts shall be received in trust for the benefit of the
Secured Party hereunder, shall be segregated from other funds of Debtor, and
shall promptly be paid over to the Secured Party in the same form as so received
(with any necessary endorsement) to be held as Collateral. Debtor shall not
adjust, settle, or compromise the amount or payment of any receivable, or
release wholly or partly any account debtor or obligor thereof, or allow any
credit or discount thereon except in the ordinary course of business in
accordance with past practices.

         6.5. Special Provisions for Collateral Located in Louisiana. The
following shall apply if the foreclosure rights and remedies are governed by the
laws of Louisiana. Upon the existence and during the continuance of an Event of
Default, the Secured Party shall have the right to cause the Collateral to be
seized and sold under Louisiana executory or ordinary process, at the Secured
Party's sole option, without appraisement, appraisement being hereby expressly
waived, as an entirety or in portions as the Secured Party may determine, to the
highest bidder for cash, and otherwise exercise the rights, powers and remedies
afforded herein and under applicable Louisiana law. For purposes of Louisiana
executory process, the Debtor acknowledges the Secured Obligations and does
hereby confess judgment in favor of the Secured Party for the full amount of the
Secured Obligations not paid when due. Any and all declarations of fact made by
authentic act before a notary public in the presence of two witnesses by a
person declaring that such facts lie within his knowledge shall constitute
authentic evidence of such facts for the purpose of executory process. Each of
the Debtor hereby waives: (a) the benefit of appraisement as provided in
Louisiana Code of Civil Procedure Articles 2332, 2336, 2723 and 2724, and all
other laws conferring the same; (b) the demand and three days' delay accorded by
Louisiana Code of Civil Procedure Articles 2639 and 2721; (c) the notice of
seizure required by Louisiana Code of Civil Procedure Articles 2293 and 2721;
(d) the three days' delay provided by Louisiana Code of Civil Procedure Articles
2331 and 2722; and (e) the benefit of the other provisions of Louisiana Code of
Civil Procedure Articles 2331, 2722 and 2723, not specifically mentioned above.
In the event the Collateral or any part thereof is seized as an incident to an
action for the



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recognition or enforcement of this Security Agreement by executory process,
ordinary process, sequestration, writ of fieri facias, or otherwise, each of the
Debtor and Secured Party agrees that the court issuing any such order shall, if
petitioned for by the Secured Party, direct the applicable sheriff to appoint as
a keeper of the Collateral, the Secured Party or any agent designated by the
Secured Party or any person named by the Secured Party at the time such seizure
is effected. This designation of a keeper will be pursuant to Louisiana Revised
Statutes 9:5136-9:5140.2 and the Secured Party or its agent shall be entitled to
all the rights and benefits of a keeper afforded thereunder as the same may be
amended. It is hereby agreed that the keeper shall be entitled to receive as
compensation, in excess of its costs and expenses incurred in the administration
or preservation of the Collateral, an amount equal to $100.00 per day, which
shall be payable on the first business day of each month. Such amounts shall
also be included in the Secured Obligations. The Secured Party shall not be
obligated to petition the court for the appointment of a keeper.

         6.6. Application of Collateral. The proceeds of any sale, or other
realization upon all or any part of the Collateral shall be applied by the
Secured Party in accordance with the terms of Section 3.3(a) of the
Intercreditor Agreement.

SECTION 7. Secured Party as Attorney-in-Fact for Debtor.

         7.1. Attorney-In-Fact. The Debtor hereby irrevocably appoints the
Secured Party as the Debtor's attorney-in-fact, with full authority to, after
the occurrence and during the continuance of an Event of Default, to act for the
Debtor and in the name of the Debtor, in the Secured Party's discretion upon the
occurrence and during the continuance of Default, to file one or more financing
or continuation statements, and amendments thereto, relative to all or any part
of the Collateral without the signature of the Debtor where permitted by law, to
receive, endorse, and collect any drafts or other instruments, documents, and
chattel paper which are part of the Collateral, and to ask, demand, collect, sue
for, recover, compromise, receive, and give acquittance and receipts for moneys
due and to become due under or in respect of any of the Collateral and to grant
or issue any exclusive or non-exclusive license under the Intellectual Property
and to file any claims or take any action or institute any proceedings which the
Secured Party may reasonably deem necessary or desirable for the collection of
any of the Collateral or otherwise to enforce the rights of the Secured Party
with respect to any of the Collateral.

         The power of attorney granted hereby is coupled with an interest and is
irrevocable.

         7.2. Secured Party Performance. If Debtor fails to perform any covenant
contained herein, the Secured Party may itself perform, or cause performance of,
such covenant, and such Debtor shall pay for the reasonable expenses of the
Secured Party incurred in connection therewith in accordance with Section 8.1.

         7.3. Secured Party's Duties. The powers conferred on the Secured Party
under this Security Agreement are solely to protect its interest in the
Collateral and shall not impose any duty upon it to exercise any such powers.
Except for the reasonable care of



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any Collateral in its possession and the accounting for monies or other property
actually received by it hereunder, the Secured Party shall have no duty as to
any Collateral or as to the taking of any necessary steps to preserve rights
against prior parties or any other rights pertaining to any Collateral. The
Secured Party shall be deemed to have exercised reasonable care as to the
custody and preservation of the Collateral in its possession if the Collateral
is accorded treatment substantially equal to that which the Secured Party
accords its own property.

SECTION 8. Miscellaneous.

         8.1. Expenses. Debtor shall upon demand pay to the Secured Party for
its benefit and the benefit of the other Noteholders the amount without
duplication of any reasonable expenses, including the reasonable fees and
disbursements of its counsel and of any experts and agents, which the Secured
Party and the other Noteholders may incur in connection with (a) the custody,
preservation, use, or operation of, or the sale, collection, or other
realization of, any of the Collateral, (b) the exercise or enforcement of any of
the rights of the Secured Party or any other Noteholder hereunder, and (c) the
failure by such Debtor to perform or observe any of the provisions hereof.

         8.2. Amendments; Etc. No amendment or waiver of any provision of this
Security Agreement nor consent to any departure by Debtor from the terms of this
Security Agreement shall be effective unless the same shall be in writing and
signed by the Debtor and the Secured Party, as collateral agent on behalf of the
Noteholders, pursuant to the Intercreditor Agreement, and then such waiver or
consent shall be effective only in the specific instance and for the specific
purpose for which given.

         8.3. Addresses for Notices. All notices and other communications
provided for hereunder shall be made as provided in the Note Purchase Agreement.
All such notices and other communications shall be effective as provided in the
Note Purchase Agreement.

         8.4. Continuing Security Interest; Transfer of Interest. This Security
Agreement shall create a continuing security interest in the Collateral and
shall (a) remain in full force and effect until indefeasible payment in full and
termination of the Secured Obligations (other than indemnification obligations),
(b) be binding upon the Debtor, the Secured Party, the Noteholders and their
respective successors, and assigns, and (c) inure, together with the rights and
remedies of the Secured Party hereunder, to the benefit of, and be binding upon,
the Secured Party, the Noteholders, and their respective successors,
transferees, and assigns. Without limiting the generality of the foregoing
clause, when any Noteholder assigns or otherwise transfers any interest held by
it under the Note Purchase Agreement to any other Person pursuant to the terms
of the Note Purchase Agreement that other Person shall thereupon become vested
with all the benefits held by such Noteholder under this Security Agreement.
Upon the indefeasible payment in full and termination of the Secured
Obligations, the security interest granted hereby shall terminate and all rights
to the Collateral shall revert to the Debtor to the extent such Collateral shall
not have been sold or otherwise applied pursuant to the terms hereof.



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         8.5. Waiver of Rights of Appraisement. The Debtor hereby expressly
waive the rights of appraisement, notice, or delay and expressly agrees to the
immediate seizure of the Collateral in the event of suit thereon.

         8.6. Waiver of Jury Trial. THE DEBTOR AGREES TO WAIVE THEIR RESPECTIVE
RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT
OF THIS SECURITY AGREEMENT OR ANY DEALINGS RELATING TO THE SUBJECT MATTER OF THE
TRANSACTIONS CONTEMPLATED HEREBY. THE SCOPE OF THIS WAIVER IS INTENDED TO BE
ALL-ENCOMPASSING OF ANY AND ALL DISPUTES THAT MAY BE FILED IN ANY COURT AND THAT
RELATE TO THE SUBJECT MATTER OF SUCH TRANSACTIONS, INCLUDING WITHOUT LIMITATION,
CONTRACT CLAIMS, TORT CLAIMS, BREACH OF DUTY CLAIMS AND ALL OTHER COMMON LAW AND
STATUTORY CLAIMS. THE SECURED PARTY AND THE DEBTOR EACH ACKNOWLEDGE THAT THIS
WAIVER IS A MATERIAL INDUCEMENT IN ENTERING INTO THIS SECURITY AGREEMENT, AND
THAT EACH WILL CONTINUE TO RELY ON THE WAIVER IN THEIR RELATED FUTURE DEALINGS.
THE DEBTOR FURTHER WARRANT AND REPRESENT THAT EACH HAS REVIEWED THIS WAIVER WITH
ITS LEGAL COUNSEL, AND THAT DEBTOR KNOWINGLY AND VOLUNTARILY WAIVES ITS JURY
TRIAL RIGHTS FOLLOWING CONSULTATION WITH LEGAL COUNSEL. IN THE EVENT OF
LITIGATION, THIS SECURITY AGREEMENT MAY BE FILED AS A WRITTEN CONSENT TO A TRIAL
BY THE COURT.

         8.7. Choice of Law. This Security Agreement shall be governed by and
construed and enforced in accordance with the laws of the State of Texas,
without giving effect to any conflict of laws provisions thereof, except to the
extent that the validity or perfection of the security interests hereunder, or
remedies hereunder, in respect of any particular Collateral are governed by the
laws of a jurisdiction other than the State of Texas. Notwithstanding anything
to the contrary in this Section, the rights, duties, immunities, indemnities and
standard of care of Wilmington Trust Company, individually, and as Collateral
Agent and Secured Party shall be governed by and construed in accordance with
the laws of the State of Delaware.

                          [Signatures on the next page]



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         The parties hereto have caused this Security Agreement to be duly
executed as of the date first above written.


                            DEBTOR:

                            Probex Fluids Recovery, Inc., a Delaware corporation


                            By: /s/  BRUCE A. HALL
                               -------------------------------------------------
                               Name: Bruce A. Hall
                               Title: Vice President


                            Address:    13355 Noel Road, Suite 1200
                                        Dallas, Texas 75240
                            Attention:  Bruce Hall
                                             Telecopy No. 972/980-8545



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                              COLLATERAL AGENT:

                              WILMINGTON TRUST COMPANY


                              By: /s/ JOSEPH B. FEIL
                                  ----------------------------------------------
                              Name: Joseph B. Feil
                              Title: Senior Financial Services Officer

                              Address:   Wilmington Trust Company
                                         1100 North Market Street
                                         Rodney Square North
                                         Wilmington, DE 19890-0001
                              Attention: Corporate Trust Administration - Probex



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                        [SCHEDULES INTENTIONALLY OMITTED]





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