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                                                                    Exhibit 4.6

                            LYONDELL CHEMICAL COMPANY
                RESTRICTED STOCK PLAN FOR NON-EMPLOYEE DIRECTORS

1.   Purpose.

     The Restricted Stock Plan for Non-Employee Directors of Lyondell Chemical
     Company (the "Plan") is intended to provide non-employee directors of
     Lyondell Chemical Company (the "Company") with an increased proprietary
     interest in the Company's success and progress by granting them shares of
     the Company's Common Stock ("Common Stock") that are restricted according
     to the terms and conditions set forth below ("Restricted Shares"). The Plan
     is intended to increase the alignment of non-employee directors with the
     Company's shareholders in terms of both risk and reward.

2.   Administration.

     The Plan is administered by a committee (the "Committee") of independent
     members of the Company's Board of Directors (the "Board") designated by the
     Board. The Committee shall have all necessary authority and discretion to
     interpret any Plan provision or to determine any question regarding
     Restricted Shares grants under this Plan. The Committee's determination or
     interpretations shall be final, conclusive and binding on all persons.

3.   Eligibility.

     All current or subsequently elected members of the Company's Board of
     Directors who are not current employees of the Company or any of its
     subsidiaries ("Eligible Directors") shall be eligible to participate in the
     Plan.

4.   Grants.

     (a) Awards. Eligible Directors shall receive an annual incentive award
         divided equally into a Restricted Shares award and an associated
         Deferred Cash Payment (as defined in Section 6). The Committee shall
         determine the amount of the award annually in its discretion, and may
         vary among Eligible Directors. The date on when Committee determines
         the annual incentive award amount is the "Grant Date."

     (b) Terms. Restricted Share awards to Eligible Directors shall be on the
         terms and conditions the Committee determines from time to time and
         with the restrictions set forth in Section 5. Deferred Cash Payments
         shall be subject to Section 6.

     (c) Number of Restricted Shares. The number of Restricted Shares granted
         shall be determined by dividing the dollar amount of the portion of the
         award allocable to Restricted Shares by the closing price of a share of
         Common Stock on the last trading day of the calendar year before the
         calendar year when the Grant Date occurs.

     (d) New Directors. A person who becomes an Eligible Director after the
         Grant Date for a calendar year shall receive a prorated annual
         Restricted Share award, based on the number of remaining months in the
         calendar year after the first day of the month when the person became
         an Eligible Director. The number of Restricted Shares awarded shall be
         determined by dividing the prorated amount allocable to the partial
         year by the closing price of a share of Common Stock on the first
         trading day of the month after the month when the person became an
         Eligible Director.

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5.   Terms and Conditions of Restricted Shares.

     (a) General. Each Restricted Share award shall be subject to the
         restrictions under subsection (b) for the Restricted Period. Restricted
         Shares awarded under the Plan prior to January 1, 2003 shall have the
         terms and restrictions set forth in the Plan on the date those
         Restricted Shares were awarded and in the applicable granting
         agreement.

     (b) Restrictions. The Restricted Shares shall be subject to a substantial
         risk of forfeiture until the Restricted Period expires. An Eligible
         Director shall have all ownership rights and privileges of a
         shareholder for the Restricted Shares, including the right to receive
         dividends and the right to vote such Restricted Shares, but the
         following restrictions shall apply: (i) an Eligible Director shall not
         be entitled to delivery of the certificate until the Restricted Period
         expires, (ii) none of the Restricted Shares may be sold, transferred,
         assigned, pledged, or otherwise encumbered or disposed of during the
         Restricted Period, and (iii) all Restricted Shares grants shall be
         forfeited and all rights of an Eligible Director to Restricted Shares
         shall terminate without further obligation on the Company's part if the
         Eligible Director terminates service prior to the date the Restricted
         Period lapses.

     (c) Restricted Period. The Restricted Period for any award of Restricted
         Shares shall begin on the Grant Date and shall lapse on the tenth
         anniversary of the Grant Date or, if earlier, the date specified in
         subsection (d).

         During the Restricted Period, the Restricted Shares may be held as a
         stock certificate representing the number of Restricted Shares awarded
         and may be registered in each Eligible Director's name but held in
         custody in the Plan's custody for the Eligible Director's account and
         not released to the Eligible Director until the Restricted Shares
         become vested when the Restricted Period lapses.

     (d) Termination of Directorship. If an Eligible Director ceases to be a
         Company director due to Disability, Death, Retirement, Change of
         Control or failure to be re-nominated to serve for any reason other
         than Cause, the Restricted Period shall lapse and the Restricted Shares
         granted to that Eligible Director shall vest immediately. If an
         Eligible Director ceases to be a director of the Company for any other
         reason, the Eligible Director shall forfeit immediately all Restricted
         Shares, unless a majority of the Board, other than the Eligible
         Director, determines that termination of director service is in the
         Company's best interest approves the lapse of the Restricted Period and
         vests the Restricted Shares. On vesting, except as provided in Section
         7, all restrictions on those Restricted Shares shall lapse and a
         certificate for those shares shall be delivered to the Eligible
         Director, or the Eligible Director's beneficiary or estate, according
         to subsection (e).

         For purposes of this section, the following definitions apply:

         (i)  "Disability" shall mean a permanent and total disability as
              defined in Section 22(e)(3) of the Internal Revenue Code.

         (ii) "Retirement" shall mean ceasing to be a Company director (i) on or
              after age 72 or (ii) at any time prior to age 72 with the consent
              of a majority of Board members, other than the Eligible Director.

         (iii)"Change of Control" shall mean a change of control as defined in
              the Company's Elective Deferral Plan for Non-Employee Directors,
              as in effect from time to time.

         (iv) "Cause" shall mean failure to diligently and prudently carry out
              the duties of a director, as determined by a majority of the Board
              members other than the affected director.

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     (e) Delivery of Restricted Shares. At the end of the Restricted Period, a
         stock certificate for the number of Restricted Shares shall be
         delivered free of all restrictions to the Eligible Director or the
         Eligible Director's beneficiary or estate, as the case may be.

6.   Deferred Cash Payment.

     Each Eligible Director shall receive a cash payment (the "Deferred Cash
     Payment") from the Company within thirty business days after the date
     Restricted Shares vest when the Restricted Period lapses or, if applicable,
     after the date Restricted Shares are forfeited. The amount of the Deferred
     Cash Payment shall be equal to the closing price per share of Common Stock
     on the trading date coincident with or next following the date the
     Restricted Shares vest or are forfeited, multiplied by the number of vested
     or forfeited Restricted Shares.

7.   Regulatory Compliance.

     An Eligible Director or an Eligible Director's beneficiary or estate shall
     not receive or sell any Common Stock granted pursuant to this Plan until
     all appropriate listing, registration and qualification requirements and
     consents and approvals have been satisfied or obtained, free of any
     condition unacceptable to the Board.

     The Committee shall have the authority to remove any or all of the
     restrictions on the Restricted Shares, including restrictions under the
     Restricted Period, whenever it determines that such action is appropriate
     as a result of changes in applicable laws or other circumstances after the
     grant date.

8.   Shares Reserved Under the Plan.

     The shares of Common Stock covered by grants under this Plan as Restricted
     Shares will not exceed 200,000 shares in the aggregate, subject to
     adjustment as provided below, according and subject to Rule 16b-3 of the
     Securities and Exchange Act of 1934 ("Exchange Act"), as amended.
     Restricted Shares may be originally issued or treasury shares or a
     combination of both.

     Any shares of Common Stock granted as Restricted Shares that are
     terminated, forfeited or surrendered or which expire for any reason will
     not be available again for issuance under this Plan, if any Eligible
     Director received any of the benefits of shares ownership before
     termination, forfeiture or surrender.

     If a recapitalization, stock split, stock dividend, combination or exchange
     of shares, merger, consolidation, rights offering, separation,
     reorganization or liquidation, or any other change in the Company's
     corporate structure or shares occurs, the Committee may make equitable
     adjustments in the number and class of shares authorized to be granted as
     Restricted Shares, as it deems appropriate to prevent dilution or
     enlargement of rights. Shares issued as a consequence of any such change
     shall be issued subject to the same restrictions and provisions applicable
     to the original Restricted Shares grant.

9.   Plan Termination or Amendment.

     The Committee at any time may terminate the Plan and from time to time may
     alter or amend all or any part of the Plan (including any amendment deemed
     necessary to ensure that the Company complies with any regulatory
     requirement in Section 7) without shareholder approval. No Plan termination
     or amendment may impair the rights of an Eligible Director to awards of
     Restricted Shares and associated Deferred Cash Payments granted under the
     Plan without the Director's consent. In addition, no Plan amendment shall
     be made without the approval of the Company's shareholders to the extent
     such approval is required by law or agreement or if such amendment would:

     (a) materially increase the benefits accruing to Eligible Directors under
         the Plan;

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     (b) materially increase the number of shares of Common Stock authorized for
         grant under Section 8 of the Plan;

     (c) materially modify the requirements for participation in the Plan, as
         provided under Section 3 of the Plan;

     (d) allow the creation of types of awards other than as provided under
         Section 4 of the Plan; or

     (e) change any of the provisions of this Section 9.

10.  Miscellaneous.

     Nothing in the Plan shall be deemed to create any Board obligation to
     nominate any director for reelection by the Company's shareholders.

     The Company shall have the right to require that an Eligible Director pay
     any taxes required by law on share issuance or delivery when the
     restrictions lapse before any Restricted Shares are issued or delivered.

11.  Governing Law.

     The Plan shall be construed according to the law of the State of Texas if
     federal law does not supersede and preempt state law.

12.  Effective Date.

     The Plan was originally effective on June 1, 1996, and was amended and
     restated effective October 16, 1998. The Plan is amended and restated
     effective January 1, 2003, subject to shareholder approval of the Plan at
     the Company's 2003 Annual Meeting of Shareholders.