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                                                                     EXHIBIT 2.1


                       CERTIFICATE OF OWNERSHIP AND MERGER

                                     MERGING

                        STERLING CHEMICALS HOLDINGS, INC.

                                      INTO

                            STERLING CHEMICALS, INC.

           (Under Section 253 of the Delaware General Corporation Law)

         Sterling Chemicals Holdings, Inc., a Delaware corporation (the
"Corporation") hereby certifies:

         FIRST: That the Corporation owns all of the outstanding shares of each
class of the capital stock of Sterling Chemicals, Inc., originally incorporated
as STX Chemicals Corp. and the original Certificate of Incorporation of which
was filed with the Secretary of State of the State of Delaware on May 10, 1996
(the "Subsidiary").

         SECOND: That pursuant to the terms of the confirmation order (the
"Order") entered by the United States Bankruptcy Court for the Southern District
of Texas on November 21, 2002 in the reorganization proceeding styled In re
Sterling Chemicals Holdings, Inc., et al., Case No. 01-37805-H4-11, which
confirmed the Joint Plan of Reorganization of the Corporation dated October 14,
2002 (the "Joint Plan of Reorganization"), the Corporation shall, pursuant to
Section 253 of the Delaware General Corporation Law (the "DGCL"), merge with and
into the Subsidiary, with the Subsidiary to be the surviving corporation, and,
except as otherwise provided in the Joint Plan of Reorganization, the Subsidiary
shall assume all of the Corporation's liabilities and obligations in order,
among other things, to put into effect and carry out the terms of the Order and
the Joint Plan of Reorganization.

         THIRD: That upon the filing of this Certificate of Ownership and
Merger, notwithstanding Section 253(a) of the Delaware General Corporation Law,
the treatment of stockholders of the Corporation and the surviving corporation
shall be as set forth in the Joint Plan of Reorganization, as effectuated
pursuant to Section 303 of the DGCL, and as a result thereof (i) no shares of
capital stock of the Subsidiary shall be issued to the holders of any shares of
stock of the Corporation outstanding immediately prior to such filing upon
surrender of certificates therefor but instead all such shares of stock of the
Corporation shall be deemed cancelled and extinguished simultaneously with the
filing of this Certificate of Ownership and Merger; (ii) all shares of stock of
the Subsidiary outstanding immediately prior to such filing shall be deemed
cancelled and extinguished simultaneously with the filing of this Certificate of
Ownership and Merger; and (iii) the holders of Old Discount Notes shall receive
the Merger Consideration (as such terms are defined in the Joint Plan of
Reorganization).

         FOURTH: That in accordance with Section 303 of the Delaware General
Corporation Law, in lieu of resolutions of the Board of Directors authorizing
the same, the undersigned, an officer of the Corporation and the Subsidiary
authorized by the Order, has been directed to execute this Certificate of
Ownership and Merger and to file the same in the office of the Secretary of
State of the State of Delaware.

         FIFTH: That from the period after the filing of this Certificate of
Ownership and Merger until the Effective Date (as such term is defined in the
Joint Plan of Reorganization) the members of the Board of Directors of the
Corporation shall serve as the Board of Sterling Chemicals, Inc. until replaced
on the Effective Date pursuant to the Joint Plan of Reorganization.

         SIXTH: That the merger herein provided for shall become effective
at       (Delaware time) on December   , 2002.



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         IN WITNESS WHEREOF, Sterling Chemicals Holdings, Inc. and Sterling
Chemicals, Inc. have each caused their corporate seals to be affixed and this
Certificate of Ownership and Merger to be signed by David G. Elkins, their
authorized officer, this      day of December, 2002.


                                   STERLING CHEMICALS HOLDINGS, INC.



                                   By:
                                       -----------------------------------------
                                          David G. Elkins
                                          President
                                          Co-Chief Executive Officer



                                   STERLING CHEMICALS, INC.



                                   By:
                                       -----------------------------------------
                                          David G. Elkins
                                          President
                                          Co-Chief Executive Officer





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