EXHIBIT 99.9

                                    FORM OF

                           LYONDELL CHEMICAL COMPANY

                         NOTICE OF GUARANTEED DELIVERY

                                      FOR

                           TENDER OF ALL OUTSTANDING

                          10 7/8% SENIOR SUBORDINATED
                                NOTES DUE 2009
                          IN EXCHANGE FOR REGISTERED
                          10 7/8% SENIOR SUBORDINATED
                                NOTES DUE 2009

     This form, or one substantially equivalent hereto, must be used by a holder
to accept the Exchange Offer of Lyondell Chemical Company (the "Issuer"),
Lyondell Chemical Worldwide, Inc. and Lyondell Chemical Nederland, Ltd.
(together, the "Subsidiary Guarantors") and to tender outstanding unregistered
10 7/8% Senior Subordinated Notes Due 2009 (the "Outstanding Notes") to The Bank
of New York, as exchange agent (the "Exchange Agent") pursuant to the guaranteed
delivery procedures described in "The Exchange Offers--Guaranteed Delivery
Procedures" of the prospectus dated           , 1999 (the "Prospectus") and in
Instruction 2 to the related Letter of Transmittal. Any holder who wishes to
tender Outstanding Notes pursuant to such guaranteed delivery procedures must
ensure that the Exchange Agent receives this Notice of Guaranteed Delivery,
properly completed and duly executed, prior to the Expiration Date (as defined
below) of the Exchange Offer. Capitalized terms used but not defined herein have
the meanings ascribed to them in the Prospectus or the Letter of Transmittal.

     THIS NOTICE OF GUARANTEED DELIVERY PERTAINS ONLY TO THE ISSUER'S OFFER TO
EXCHANGE ITS 10 7/8% SENIOR SUBORDINATED NOTES DUE 2009.  THE ISSUER IS
CONCURRENTLY MAKING SEPARATE, INDEPENDENT OFFERS TO EXCHANGE ITS UNREGISTERED
9 5/8% SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES,
SERIES B, DUE 2007 FOR A LIKE KIND AND PRINCIPAL AMOUNT OF ITS REGISTERED 9 5/8%
SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES, SERIES
B, DUE 2007, RESPECTIVELY. HOLDERS ALSO HOLDING THE ISSUER'S 9 5/8% SENIOR
SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES, SERIES B, DUE
2007 WHO WISH TO PARTICIPATE IN THE SEPARATE, INDEPENDENT EXCHANGE OFFERS
RELATING TO SUCH NOTES WILL NEED TO COMPLETE AND RETURN THE APPLICABLE
DOCUMENTATION RELATING TO SUCH NOTES.

THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
______________________, 1999, UNLESS EXTENDED (THE "EXPIRATION DATE").
OUTSTANDING NOTES TENDERED IN THE EXCHANGE OFFER MAY BE WITHDRAWN AT ANY TIME
PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE FOR THE EXCHANGE
OFFER.

                 The Exchange Agent for the Exchange Offer is:

                              THE BANK OF NEW YORK

By Courier:                  By Mail (registered or             By Hand:
                          certified mail recommended):
   THE BANK OF NEW YORK        THE BANK OF NEW YORK            101 BARCLAY ST.
      101 BARCLAY ST.       101 BARCLAY ST., FLOOR 7E   CORPORATE TRUST SERVICES
 CORPORATE TRUST SERVICES      NEW YORK, NY  10286                 WINDOW
         WINDOW                ATTN:  REORG. DEPT.              GROUND LEVEL
       GROUND LEVEL                                          NEW YORK, NY  10286
    NEW YORK, NY  10286                                      ATTN:  REORG. DEPT.
     ATTN:  REORG. DEPT.


            By Facsimile Transmission (eligible institutions only):

                                 (212) 815-4699

                       Attn:
                            ------------------------

                             Confirm by Telephone:
                                 (212) 815-2742



     DELIVERY OF THIS INSTRUMENT TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE, OR
TRANSMISSION VIA FACSIMILE TO A NUMBER OTHER THAN AS SET FORTH ABOVE, WILL NOT
CONSTITUTE A VALID DELIVERY.  THE INSTRUCTIONS ACCOMPANYING THIS NOTICE OF
GUARANTEED DELIVERY SHOULD BE READ CAREFULLY BEFORE THE NOTICE OF GUARANTEED
DELIVERY IS COMPLETED.

     THIS NOTICE OF GUARANTEED DELIVERY IS NOT TO BE USED TO GUARANTEE
SIGNATURES.  IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE
GUARANTEED BY AN "ELIGIBLE INSTITUTION" UNDER THE INSTRUCTIONS THERETO, SUCH
SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE IN THE BOX PROVIDED ON
THE LETTER OF TRANSMITTAL FOR GUARANTEE OF SIGNATURES.

Ladies and Gentlemen:

     The undersigned hereby tenders to the Issuer, in accordance with the
Issuer's offer, upon the terms and subject to the conditions set forth in the
Prospectus and the related Letter of Transmittal, receipt of which is hereby
acknowledged, the principal amount of Outstanding Notes set forth below pursuant
to the guaranteed delivery procedures set forth in the Prospectus under the
caption "The Exchange Offers--Guaranteed Delivery Procedures" and in Instruction
2 of the Letter of Transmittal.

     THIS NOTICE OF GUARANTEED DELIVERY PERTAINS ONLY TO THE ISSUER'S OFFER TO
EXCHANGE ITS 10 7/8% SENIOR SUBORDINATED NOTES DUE 2009.  THE ISSUER IS
CONCURRENTLY MAKING SEPARATE, INDEPENDENT OFFERS TO EXCHANGE ITS UNREGISTERED
9 5/8% SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES,
SERIES B, DUE 2007 FOR A LIKE KIND AND PRINCIPAL AMOUNT OF ITS REGISTERED
9 5/8% SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES,
SERIES B, DUE 2007, RESPECTIVELY. HOLDERS ALSO HOLDING THE ISSUER'S 9 5/8%
SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES, SERIES
B, DUE 2007 WHO WISH TO PARTICIPATE IN THE SEPARATE, INDEPENDENT EXCHANGE OFFERS
RELATING TO SUCH NOTES WILL NEED TO COMPLETE AND RETURN THE APPLICABLE
DOCUMENTATION RELATING TO SUCH NOTES.

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     The undersigned hereby tenders the Outstanding Notes listed below:




 Title of Series                  Certificate Number(s) (if known)       Aggregate Principal      Aggregate Principal
                                  of Outstanding Notes or Account        Amount Represented         Amount Tendered
                                  Number at the Book-entry Facility
                                                                                         
Lyondell Chemical Company
 10 7/8% Senior Subordinated
 Due 2009


                           PLEASE SIGN AND COMPLETE


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- -------------------------------------   ----------------------------------------
Name(s) of Registered Holder(s)         Signatures of Registered Holder(s) or
                                        Authorized Signatory

- -------------------------------------

- -------------------------------------
Address
                                        Dated                            , 1999
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Area Code and Telephone Number(s)

          THIS NOTICE OF GUARANTEED DELIVERY MUST BE SIGNED BY THE REGISTERED
HOLDER(S) OF OUTSTANDING NOTES EXACTLY AS THE NAME(S) OF SUCH PERSON(S)
APPEAR(S) ON CERTIFICATES FOR OUTSTANDING NOTES OR ON A SECURITY POSITION
LISTING AS THE OWNER OF OUTSTANDING NOTES, OR BY PERSON(S) AUTHORIZED TO BECOME
HOLDER(S) BY ENDORSEMENTS AND DOCUMENTS TRANSMITTED WITH THIS NOTICE OF
GUARANTEED DELIVERY.  IF SIGNATURE IS BY A TRUSTEE, EXECUTOR, ADMINISTRATOR,
GUARDIAN, ATTORNEY-IN-FACT, OFFICER OR OTHER PERSON ACTING IN A FIDUCIARY OR
REPRESENTATIVE CAPACITY, SUCH PERSON MUST PROVIDE THE FOLLOWING INFORMATION:

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                      Please print name(s) and address(es)

Name(s):

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Capacity:

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Address(es):

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                                   GUARANTEE

                    (Not to be used for signature guarantee)

          The undersigned, a firm which is a member firm of a registered
national securities exchange or of the National Association of Securities
Dealers, Inc., or is a commercial bank or trust company having an office or
correspondent in the United States, or is otherwise an "eligible guarantor
institution" within the meaning of Rule 17Ad-15 under the Securities Exchange
Act of 1934, hereby guarantees deposit with the Exchange Agent of the Letter of
Transmittal (or facsimile thereof or agent's message in lieu thereof), together
with the Outstanding Notes tendered hereby in proper form for transfer (or
confirmation of the book-entry transfer of such Outstanding Notes into the
Exchange Agent's account at the DTC described in the Prospectus under the
caption "The Exchange Offers--Book-entry Transfer" and in the Letter of
Transmittal) and any other required documents, all by 5:00 p.m., New York City
time, within five New York Stock Exchange trading days following the Expiration
Date for such series.


Name of Firm:
             ---------------------------   --------------------------------
                                           (Authorized Signature)

Address:                                   Name:
        --------------------------------        ---------------------------
              (Include Zip Code)           Title:
                                                 --------------------------
                                                   (Please Type or Print)
Area Code and Telephone Number:

- ----------------------------------------   Date:                     , 1999
                                                ---------------------

     DO NOT SEND OUTSTANDING NOTES WITH THIS FORM.  ACTUAL SURRENDER OF
OUTSTANDING NOTES MUST BE MADE PURSUANT TO, AND BE ACCOMPANIED BY, A PROPERLY
COMPLETED AND DULY EXECUTED LETTER OF TRANSMITTAL AND ANY OTHER REQUIRED
DOCUMENTS.

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                 INSTRUCTIONS FOR NOTICE OF GUARANTEED DELIVERY

     1.   DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY.  A properly completed
and duly executed copy of this Notice of Guaranteed Delivery (or facsimile
hereof or an agent's message and Notice of Guaranteed Delivery in lieu hereof)
and any other documents required by this Notice of Guaranteed Delivery with
respect to the Outstanding Notes must be received by the Exchange Agent at its
address set forth herein prior to the Expiration Date of the Exchange Offer.
THE METHOD OF DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY AND ANY OTHER
REQUIRED DOCUMENTS TO THE EXCHANGE AGENT IS AT THE ELECTION AND SOLE RISK OF THE
HOLDER, AND THE DELIVERY WILL BE DEEMED MADE ONLY WHEN ACTUALLY RECEIVED BY THE
EXCHANGE AGENT.  If delivery is by mail, registered mail with return receipt
requested, properly insured, is recommended.  As an alternative to delivery by
mail, holders may wish to consider using an overnight or hand delivery service.
In all cases, sufficient time should be allowed to ensure timely delivery.  For
a description of the guaranteed delivery procedures, see Instruction 2 of the
Letter of Transmittal.

     THIS NOTICE OF GUARANTEED DELIVERY PERTAINS ONLY TO THE ISSUER'S OFFER TO
EXCHANGE ITS 10 7/8% SENIOR SUBORDINATED NOTES DUE 2009.  THE ISSUER IS
CONCURRENTLY MAKING SEPARATE, INDEPENDENT OFFERS TO EXCHANGE ITS UNREGISTERED
9 5/8% SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES,
SERIES B, DUE 2007 FOR A LIKE KIND AND PRINCIPAL AMOUNT OF ITS REGISTERED 9 5/8%
SENIOR SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES, SERIES
B, DUE 2007, RESPECTIVELY. HOLDERS ALSO HOLDING THE ISSUER'S 9 5/8% SENIOR
SECURED NOTES, SERIES A, DUE 2007 AND 9 7/8% SENIOR SECURED NOTES, SERIES B, DUE
2007 WHO WISH TO PARTICIPATE IN THE SEPARATE, INDEPENDENT EXCHANGE OFFERS
RELATING TO SUCH NOTES WILL NEED TO COMPLETE AND RETURN THE APPLICABLE
DOCUMENTATION RELATING TO SUCH NOTES.

     2.   SIGNATURES ON THIS NOTICE OF GUARANTEED DELIVERY.  If this Notice of
Guaranteed Delivery (or facsimile hereof) is signed by the registered holder(s)
of the Outstanding Notes referred to herein, the signature(s) must correspond
exactly with the name(s) written on the face of the Outstanding Notes without
alteration, enlargement, or any change whatsoever.  If this Notice of Guaranteed
Delivery (or facsimile hereof) is signed by a participant of the DTC whose name
appears on a security position listing as the owner of the Outstanding Notes,
the signature must correspond with the name shown on the security position
listing as the owner of the Outstanding Notes.

     If this Notice of Guaranteed Delivery (or facsimile hereof) is signed by a
person other than the registered holder(s) of any Outstanding Notes listed or a
participant of the DTC, this Notice of Guaranteed Delivery must be accompanied
by appropriate bond powers, signed as the name(s) of the registered holder(s)
appear(s) on the Outstanding Notes or signed as the name(s) of the participant
shown on the DTC's security position listing.

     If this Notice of Guaranteed Delivery (or facsimile hereof) is signed by a
trustee, executor, administrator, guardian, attorney-in-fact, officer of a
corporation, or other person acting in a fiduciary or representative capacity,
such person should so indicate when signing and submit with the Letter of
Transmittal evidence satisfactory to the Exchange Agent of such person's
authority to so act.

     3.   REQUESTS FOR ASSISTANCE OR ADDITIONAL COPIES.  Questions and requests
for assistance and requests for additional copies of the Prospectus and this
Notice of Guaranteed Delivery may be directed to the Exchange Agent at the
address set forth on the cover page hereof.  Holders may also contact their
broker, dealer, commercial bank, trust company or other nominee for assistance
concerning the Exchange Offer.

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