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                                                                     Exhibit 4.1

                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                            LYONDELL CHEMICAL COMPANY

                        Under Sections 242 and 245 of the
                        Delaware General Corporation Law

         LYONDELL CHEMICAL COMPANY (the "Company"), a corporation organized and
existing under and by virtue of the General Corporation Law of the State of
Delaware, does hereby certify that:

         1. The current name of the corporation is Lyondell Chemical Company.
The name under which the Company was originally incorporated was Lyondell
Petrochemical Corporation. The original Certificate of Incorporation of the
Company (as heretofore amended, the "Certificate of Incorporation") was filed
with the Secretary of State of the State of Delaware on November 15, 1985.

         2. The restatement of and amendments to the Certificate of
Incorporation have been duly adopted by a resolution of the Board of Directors
of the Company (the "Board of Directors") proposing and declaring advisable this
Amended and Restated Certificate of Incorporation, and the Company's
stockholders have duly approved and adopted the Amended and Restated Certificate
of Incorporation, all in accordance with the provisions of Sections 242 and 245
of the General Corporation Law of the State of Delaware.

         3. This Amended and Restated Certificate of Incorporation restates and
amends the Certificate of Incorporation of the Company in its entirety. The
amendments to the Certificate of Incorporation effected by this Amended and
Restated Certificate of Incorporation include, but are not limited to,
amendments to increase the number of authorized shares of capital stock that the
Company shall have the authority to issue, to provide for a Series B of common
stock, to add provisions relating to dividends, liquidation and voting with
respect to the common stock and the Series B common stock of the Company and to
delete former Article VIII.

         4. The capital of the Company shall not be reduced under or by reason
of the foregoing amendments to the Certificate of Incorporation.

         5. The Certificate of Incorporation is hereby superseded by this
Amended and Restated Certificate of Incorporation, which shall henceforth be the
Certificate of Incorporation of the Company.

         6. The text of the Restated Certificate of Incorporation is hereby
restated and amended to read in its entirety as follows (hereinafter, the
Amended and Restated Certificate of

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Incorporation, as it may be further amended or restated from time to time, is
referred to as the "Amended and Restated Certificate of Incorporation").

                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                    ARTICLE I
                                      Name

         The name of the Company is LYONDELL CHEMICAL COMPANY.

                                   ARTICLE II
                          Address and Registered Agent

         The address of the Company's registered office in the State of Delaware
is Corporation Trust Center, 1209 Orange Street, Wilmington, County of New
Castle, Delaware, 19801. The name of the registered agent at such address is The
Corporation Trust Company.

                                   ARTICLE III
                             Description of Business

         The nature of the business or purposes to be conducted or promoted is
to engage in any lawful act or activity for which corporations may be organized
under the General Corporation law of Delaware.

                                   ARTICLE IV
                                  Capital Stock

         The aggregate number of shares of capital stock that the Company shall
have authority to issue is 500,000,000, divided into two classes as follows:

         (1) 420,000,000 shares of common stock issued in two series with the
first series consisting of 340,000,000 shares, par value $1.00 per share
("Common Stock"), and the second series consisting of 80,000,000 shares of
Series B common stock, par value $1.00 per share ("Series B Common Stock"); and

         (2) 80,000,000 shares of preferred stock, par value $.01 per share
("Preferred Stock").

         (3) Shares of any class or series of capital stock of the Company may
be issued for such consideration and for such corporate purposes as the Board of
Directors may from time to time determine. Except as may be provided otherwise
in any certificate of designation for any series of preferred stock, the number
of authorized shares of any class or series of capital stock of the Company may
be increased or decreased (but not below the number of shares thereof then
outstanding) by the affirmative vote of holders of at least a majority of the
then outstanding Voting Stock (as defined below), voting as a single class. The
term "Voting Stock" shall mean all outstanding shares of all classes and series
of capital stock of the Company entitled to vote generally in the election of
Directors of the Company, considered as one class;

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and, if the Company shall have outstanding at any time shares of Voting Stock
entitled to more or less than one vote for any such share, each reference in
this Amended and Restated Certificate of Incorporation to a proportion or
percentage in voting power of Voting Stock shall be calculated by reference to
the portion or percentage of all votes entitled to be cast by holders of all
such shares generally in the election of Directors of the Company.

         The following is a statement of the powers, preferences and rights, and
the qualifications, limitations or restrictions, of the Preferred Stock, the
Common Stock and the Series B Common Stock.

                           SECTION I. PREFERRED STOCK

         Preferred Stock may be issued from time to time in one or more series.
The Board of Directors is hereby expressly authorized from time to time to
provide for the issuance of Preferred Stock in one or more series, and to
establish and fix by resolution or resolutions providing for the issuance of
each such series the number of shares to be included in such series and the
voting and other powers, designations, preferences and relative, participating,
optional or other special rights, and qualifications, limitations or
restrictions thereof, of each such series, to the full extent now or hereafter
permitted by law, subject to any other provision of this Amended and Restated
Certificate of Incorporation. The number of authorized shares of Preferred Stock
may be increased or decreased (but not below the number of shares thereof then
outstanding) by the affirmative vote of the holders of stock of the Company
entitled to vote thereon having a majority of the votes entitled to be cast,
without a separate vote of the holders of the Preferred Stock, or any series
thereof, unless a separate vote of any of such holders is required pursuant to
the resolution or resolutions establishing any such series of Preferred Stock.

                            SECTION II. COMMON STOCK

         (1) Common Stock and Series B Common Stock Otherwise Identical. Except
as otherwise set forth in this Article IV, the relative powers, preferences and
participating, optional or other special rights, and the qualifications,
limitations or restrictions of the Common Stock and the Series B Common Stock
shall be identical in all respects. The shares of Common Stock shall constitute
one series of common stock and the shares of Series B Common Stock shall
constitute a second series of common stock, and together the two series shall
constitute one class of common stock.

         (2) Dividends.

                (a) Subject to any requirements with respect to preferential or
     participating dividends as shall be provided by the express terms of any
     outstanding series of Preferred Stock and subject to Section II(2)(b),
     holders of the Common Stock and the Series B Common Stock shall be entitled
     to receive such dividends thereon, if any, as may be declared from time to
     time by the Board of Directors.

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             (b) The Board of Directors shall not declare any dividend on the
     Common Stock without declaring a dividend in the same amount and form per
     share on the Series B Common Stock; provided, however, in the event a cash
     dividend is declared on the Common Stock, the Company may, at its option
     and in its sole discretion, declare and pay the corresponding dividend on
     shares of Series B Common Stock by issuance of additional shares of fully
     paid and nonassessable shares of Series B Common Stock ("PIK Dividend").
     Any such PIK Dividend shall be declared at the same time and shall have the
     same record date as the corresponding cash dividend on Common Stock, but
     the payment date for any dividend on Series B Common Stock that is paid in
     the form of shares of Series B Common Stock shall be 10 Business Days (as
     defined below) after the payment date for the corresponding cash dividend
     on shares of Common Stock, in order that the number of shares may be
     calculated pursuant to the following sentence. The number of shares of
     Series B Common Stock to be issued in lieu of cash shall be determined by
     dividing the amount of the cash dividend per share declared with respect to
     the Common Stock by the average (calculated to the nearest thousandth) of
     the Daily Prices (as defined below) of the Common Stock for the ten
     consecutive Business Days commencing four Business Days prior to the
     payment date for the cash dividend on the Common Stock and ending five
     Business Days thereafter. For purposes of this calculation, (i) the "Daily
     Price" for any day shall mean the average (calculated to the nearest
     thousandth) of the high and low per share sales prices of the Common Stock
     on such day for sales conducted regular way, as such high and low per share
     sales prices are reported on www.nysenet.com or, if not reported thereby,
     another authoritative source and (ii) "Business Day" shall mean any day on
     which the New York Stock Exchange, Inc. is open for trading. No fractional
     shares of Series B Common Stock shall be issued as a dividend pursuant to
     the foregoing method of valuation. Instead, the aggregate number of shares
     of Series B Common Stock issuable to each record holder in accordance with
     the foregoing method of valuation shall be rounded to the nearest whole
     number. The payment of dividends to holders of Series B Common Stock in
     shares of Series B Common Stock as set forth above shall constitute full
     payment of such dividend.

         (3) Liquidation. In the event of liquidation, dissolution or winding-up
of the Company, whether voluntary or involuntary, holders of the Common Stock
and the Series B Common Stock then outstanding shall be entitled to receive such
assets and properties of the Company, tangible and intangible, as are available
for distribution to stockholders of the Company ratably in proportion to the
number of shares of Common Stock and Series B Common Stock held by each holder
(such that the Common Stock and the Class B Common Stock shall be treated
identically), after there shall have been paid or set apart for payment the full
amounts necessary to satisfy any preferential or participating rights to which
holders of each outstanding series of Preferred Stock are entitled by the
express terms of such series.

         (4) Reorganization or Merger. In the case of any reorganization,
consolidation or merger involving the Company -- except as otherwise approved by
the affirmative vote of a majority of the outstanding shares of the Common
Stock, voting as a separate class, and the affirmative vote of a majority of the
outstanding shares of Series B Common stock, voting as a separate class -- each
holder of a share of Common Stock or Series B

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Common Stock shall be entitled to receive with respect to that share the same
kind and amount of shares of stock and other securities and property (including
cash) upon the reorganization, consolidation or merger as shall be received by a
holder of a share of the other series; provided, however, that the foregoing
shall not apply to (i) any merger in which the Company is the continuing
corporation and which does not result in any distribution of shares of stock or
other securities or property (including cash) to the holders of, or any
reclassification or change in, the outstanding shares of Common Stock or Series
B Common Stock or (ii) any merger in which the Company merges with or into a
wholly owned subsidiary solely for the purpose of forming a holding company,
whether such holding company is formed without a vote of the stockholders
pursuant to Section 251(g) of the General Corporation Law of Delaware or formed
with the approval of the stockholders. In the case of a merger referred to in
clause (ii), each share of Common Stock and each share of Series B Common Stock
outstanding immediately prior to such merger shall be converted into a share of
common stock of such holding company having the same respective rights, powers
and preferences, and the same respective qualifications, limitations and
restrictions thereon, as the Common Stock or the Series B Common Stock, as the
case may be, being converted in such merger.

        (5)  Voting.

             (a) The holders of shares of Common Stock and the holders of shares
     of Series B Common Stock shall be entitled to receive notice of and to
     attend all meetings of the stockholders of the Company and to vote together
     as a single class (subject to any right that may be conferred upon holders
     of Preferred Stock to vote together with holders of Common Stock and/or
     Series B Common Stock) at all such meetings on each matter submitted to a
     vote of stockholders, except as otherwise provided by this Amended and
     Restated Certificate of Incorporation or as otherwise provided by Delaware
     law with respect to matters as to which the holders of one series of shares
     of a class of the Company's capital stock are entitled to vote separately
     as a class. Each holder of shares of Common Stock and Series B Common Stock
     shall have the right to one vote for each share of common stock held of
     record on the books of the Company.

             (b) Except as otherwise provided by Delaware law or Article VII
     hereof, the provisions of this Amended and Restated Certificate of
     Incorporation shall not be modified, revised, altered or amended, repealed
     or rescinded, in whole or in part, without the affirmative vote of holders
     of at least a majority of the then outstanding shares of Voting Stock,
     voting together as a single class; provided, however, that, except as
     provided in paragraph (c) of this Section II(5), any proposal to modify,
     revise, alter or amend this Amended and Restated Certificate of
     Incorporation (whether by merger, consolidation or otherwise) in any manner
     that would alter or change the powers, preferences or special rights of the
     shares of either the Common Stock or the Series B Common Stock so as to
     affect them adversely also will require the approval of the holders of
     shares having a majority of the votes entitled to be cast by the holders of
     the shares of the series so affected by the proposed amendment (or if such
     series is Series B Common Stock, shares having 80% of such votes), voting
     as a separate class. Any increase in the authorized number of shares of any
     class or classes of stock of the

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     Company, or the creation, authorization or issuance of any securities
     convertible into, or warrants, options or similar rights to purchase,
     acquire or receive, shares of any such class or classes of stock, shall be
     deemed not to affect adversely the powers, preferences or special rights of
     the shares of either the Common Stock or the Series B Common Stock.

             (c) The holders of Common Stock and Series B Common Stock shall
     vote together as a single class, and not as two separate series, on any
     proposal to approve (i) any reorganization, consolidation or merger in
     which each holder of a share of Common Stock and each holder of a share of
     Series B Common Stock shall be entitled to receive with respect to that
     share the same kind and amount of shares of stock and other securities and
     property (including cash) receivable upon the reorganization, consolidation
     or merger as shall be received by a holder of a share of the other such
     series, (ii) any merger of a type described in clauses (i) or (ii) of
     Section II(4) or (iii) any other merger in which the shares of stock
     receivable by the holders of Common Stock and Series B Common Stock
     pursuant thereto shall have the same respective rights, powers and
     preferences, and the same respective qualifications, limitations or
     restrictions, as the shares of Common Stock and the Series B Common Stock
     prior thereto.

        (6)  Conversion of Shares of Series B Common Stock into Common Stock.

             (a) Shares of Series B Common Stock may be converted into shares of
     Common Stock at the option of the holder at any time on or after the date
     of issuance of the shares or such later date as may be fixed by the Board
     of Directors in resolutions authorizing the issuance of such shares.

             (b) The Company may, at its option and in its sole discretion, at
     any time convert any or all shares of Series B Common Stock into shares of
     Common Stock.

             (c) Each share of Series B Common Stock properly submitted to the
     Company for conversion shall be converted into one share of fully paid and
     nonassessable Common Stock in accordance with the following:

                 (i) such right shall be exercised by the holder by surrender of
             the certificate representing such share of Series B Common Stock to
             be converted to the Company at any time during normal business
             hours to the office of the Secretary of the Company at the
             principal executive offices of the Company or, if an agent for the
             registration of transfer of shares of Series B Common Stock is then
             duly appointed and acting (said agent being hereinafter called the
             "Transfer Agent"), then at the office of the Transfer Agent,
             accompanied by (x) a written notice of the election by the holder
             thereof to convert, (y) instruments of transfer (if so required by
             the Company or the Transfer Agent) in a form reasonably
             satisfactory to the Company or the Transfer Agent, duly executed by
             such holder or his duly

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             authorized attorney and (z) transfer tax stamps or funds therefor,
             if required pursuant to subparagraph (iii) below;

                 (ii)  as promptly as practicable after the surrender for
             conversion of a certificate representing shares of Series B Common
             Stock in the manner provided in the foregoing paragraph and the
             payment in cash of any amount required by the provisions of
             subparagraph (iii) below or upon the Company's exercise of its
             conversion rights pursuant to Section II(6)(b), the Company will
             deliver or cause to be delivered at the office of the Company or
             the Transfer Agent to or upon the written order of the holder of
             such certificate, a certificate or certificates representing the
             number of full shares of Common Stock issuable upon such
             conversion, issued in such name or names as such holder may direct.
             Such conversion shall be deemed to have been made immediately prior
             to the close of business on the date of the surrender of the
             certificate representing shares of Series B Common Stock, and all
             rights of the holder of such shares as such holder shall cease at
             such time and the person or persons in whose name or names the
             certificate or certificates representing the shares of Common Stock
             are to be issued shall be treated for all purposes as having become
             the record holder or holders of such shares of Common Stock at such
             time; provided, however, that if any such surrender occurs on any
             date when the stock transfer books of the Company shall be closed,
             the person or persons in whose name or names the certificate or
             certificates representing shares of Common Stock are to be issued
             shall be treated for all purposes as having become the record
             holder or holders thereof and such conversion shall be deemed to
             have been made, immediately prior to the close of business on the
             next succeeding day on which such stock transfer books are open;
             and

                 (iii) the issuance of certificates for shares of Common Stock
             upon conversion of shares of Series B Common Stock shall be made
             without charge for any stamp or other similar tax in respect of
             such issuance; provided, however, that if any such certificate is
             to be issued in a name other than that of the holder of the share
             or shares of Series B Common Stock converted, the person or persons
             requesting the issuance thereof shall pay to the Company the amount
             of any applicable tax that may be payable in respect of any
             transfer involved in such issuance or shall establish to the
             satisfaction of the Company that such tax has been paid.

             (d) Notwithstanding the foregoing, there shall be no conversion of
     shares of Series B Common Stock into shares of Common Stock pursuant to the
     provisions of this Section II(6) in any time period commencing with the
     date a dividend is declared and ending on the related record date, after
     which record date conversion pursuant to Sections II(6)(a),(b) and (c)
     above may resume.

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          (7)  Outstanding Common Stock. Upon this Amended and Restated
Certificate of Incorporation becoming effective in accordance with Section 103
of the DGCL (the "Effective Time"), each share of common stock, par value $1.00
per share, that was issued and outstanding immediately prior to the Effective
Time shall automatically and without any action on the part of the holder
thereof or any other person be reclassified as one share of Common Stock.

                                    ARTICLE V
                   Annual and Special Meetings of Stockholders

          Any action required or permitted to be taken by the holders of the
stock of the Company may be effected either at a duly called annual or special
meeting of such holders or by consent in writing by such holders. Except as
otherwise required by law, special meetings of stockholders of the Company may
be called only by the written consent of the stockholders owning a majority of
the capital stock issued and outstanding and entitled to vote or by the Board of
Directors pursuant to a resolution approved by a majority of the entire Board of
Directors or by the Chairman of the Board.

                                   ARTICLE VI
                                    Directors

          (1)  The business and affairs of the Company shall be managed by the
Board of Directors, and the directors need not be elected by ballot unless
required by the By-Laws of the Company. The number of the directors of the
Company shall be fixed from time to time by, or in the manner provided in, the
By-Laws of the Company.

          (2)  Nominations for the election of directors may be made by the
Board of Directors or by any record owner of stock of the Company.

          (3)  Newly created directorships resulting from any increase in the
number of directors or any vacancy on the Board of Directors resulting from
death, resignation, disqualification, removal or other cause may be filled by
the affirmative vote of a majority of the remaining directors then in office,
even though less than a quorum of the Board of Directors, by a sole remaining
director or by the affirmative vote of the majority of all votes entitled to be
cast by the holders of stock of the Company at a duly called annual or special
meeting of such holders or by consent in writing by such holders. Any director
elected in accordance with the preceding sentence shall hold office until such
director's successor shall have been elected and qualified or until the
director's earlier resignation or removal. No decrease in the number of
directors constituting the Board of Directors shall shorten the term of any
incumbent director.

          (4)  Any one or more directors may be removed with or without cause,
by the holders of a majority of the shares then entitled to vote at an election
of directors.

          (5)  The Board of Directors shall have the power to adopt, amend and
repeal the By-Laws of the Company.

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                                   ARTICLE VII
                              Directors' Liability

          To the fullest extent permitted by the General Corporation Law of
Delaware as the same exists or may hereafter be amended, a director of the
Company shall not be liable to the Company or its stockholders for monetary
damages for breach of fiduciary duty as a director. If the General Corporation
Law of Delaware is amended to authorize corporate action further eliminating or
limiting the personal liability of directors, then the liability of a director
of the Company shall be eliminated or limited to the fullest extent permitted by
the General Corporation Law of Delaware, as so amended. Any repeal or
modification of this Article VII by the stockholders of the Company shall not
adversely affect any right or protection of a director of the Company existing
at the time of such repeal or modification or with respect to events occurring
prior to such time. Notwithstanding anything contained in this Amended and
Restated Certificate of Incorporation to the contrary, the affirmative vote of
the holders of not less than 66-2/3 percent of all votes entitled to be cast by
the holders of stock of the Company shall be required to amend or repeal this
Article VII or to adopt any provision inconsistent herewith.

                                  ARTICLE VIII
                              Other Considerations

          The Board of Directors of the Company, when evaluating any offer of a
person, other than the Company itself, to (a) make a tender or exchange offer
for any equity security of the Company, (b) merge or consolidate the Company
with another person or (c) purchase or otherwise acquire all or substantially
all of the properties and assets of the Company shall, in connection with the
exercise of its business judgment in determining what is in the best interests
of the Company and its stockholders, be entitled to give due consideration to
all factors that the Board of Directors determines to be relevant, including
without limitation the social and economic effects on the employees, customers,
suppliers and other constituents of the Company and its subsidiaries and on the
communities in which the Company and its subsidiaries operate or are located.


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          IN WITNESS WHEREOF, the Company has caused this Amended and Restated
Certificate of Incorporation to be signed by its duly authorized officer, this
21/st/ day of August, 2002


                                      LYONDELL CHEMICAL COMPANY


                                      By  /s/ KERRY A. GALVIN
                                          -------------------
                                          Name:  Kerry A. Galvin
                                          Title: Senior Vice President, General
                                                 Counsel & Secretary