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                                                                   EXHIBIT 10.9b


                             STERLING CHEMICALS ESOP
                               (SECOND AMENDMENT)

                  WHEREAS, there is reserved to the Chief Executive Officer of
the Company in Section 9.1 of the Sterling Chemicals ESOP (the "Plan") the right
to amend the Plan, subject to certain restrictions set forth therein; and

                  WHEREAS, the Company deems it advisable to amend the Plan;

                  NOW, THEREFORE, the Plan is hereby amended effective as of
                  August 21, 1996 as follows:

         1.       Section 4.3(g) is amended to read as follows:

                  "All Company Stock acquired by the Plan with the proceeds of
                  an Exempt Loan must be added to and maintained in the
                  Unallocated Company Stock Suspense Account. For each Plan Year
                  during the duration of the Loan, the number of shares of
                  Company Stock released shall equal the number of encumbered
                  shares held immediately before release of the current Plan
                  Year multiplied by a fraction, the numerator of which is the
                  amount of principal paid for the Plan Year and the denominator
                  of which is the sum of the numerator plus the principal to be
                  paid for all future Plan Years. In order to determine the
                  release of shares based solely on principal payments on the
                  Exempt Loan, the Exempt Loan must provide for annual payments
                  of principal and interest at a cumulative rate that is not
                  less rapid at any time than level annual payments of such
                  amounts for 10 years; interest included in the Exempt Loan
                  payment shall be disregarded only to the extent that it would
                  be determined to be interest under standard loan amortization
                  tables; and if by reason of a renewal, extension, or
                  refinancing, the sum of the expired duration of the Exempt
                  Loan, the renewal period, the extension period, and the
                  duration of the new Exempt Loan exceeds 10 years, then for
                  each Plan Year during the duration of the Exempt Loan, the
                  number of securities released must equal the number of
                  encumbered securities held immediately before release for the
                  current Plan Year multiplied by a fraction, the numerator of
                  which is the amount of principal and interest paid for the
                  year, and the denominator of which is the sum of the numerator
                  plus the principal and interest to be paid for all future
                  years. In addition, in such event the number of future years
                  under the Exempt Loan must be definitely ascertainable and
                  must be determined without taking into account any possible
                  extensions or renewal periods. If the interest rate under the
                  Exempt Loan is variable, the interest to be paid in future
                  years must be computed by using the interest rate applicable
                  as of the end of the Plan Year. If collateral includes more
                  than one class of securities, the number of securities of each
                  class to be released for a Plan Year

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                  must be determined by applying the same fraction to each
                  class. As of each Anniversary Date, the Plan must consistently
                  allocate to each Participant's Account pursuant to Section
                  4.3(b), shares and fractional shares of Company Stock
                  representing each Participant's interest in the shares
                  withdrawn from the Unallocated Company Stock Suspense Account;
                  provided, however, to the extent any cash dividends on
                  allocated shares of Company Stock have been applied to repay
                  the loan that year, the number of shares released shall first
                  be allocated to the accounts of those Participants equal in
                  amount to the cash dividends diverted from such accounts for
                  repayment of the Exempt Loan. Income earned with respect to
                  Company Stock in the Unallocated Company Stock Suspense
                  Account shall be used to repay the Exempt Loan or used to
                  purchase such Company Stock. Any income which is not so used
                  must be allocated as income of the Plan."

         2.       Section 4.6(b)(2) is amended to read as follows:

                  "Qualified Election Period means the six Plan Year period
                  beginning with the first Plan Year in which the Participant
                  first became a Qualified Participant."

                  All terms used herein that are defined in the Plan shall have
the same meanings given to such terms in the Plan, except as otherwise expressly
provided herein.

                  Except as amended and modified hereby, the Plan shall continue
in full force and effect and the Plan and this amendment shall be read, taken
and construed as one and the same instrument.

                  This amendment may be executed in several counterparts, each
of which shall be deemed an original, but all of which shall constitute but one
and the same instrument which may be evidenced by any one counterpart.

                  IN WITNESS WHEREOF, this Amendment has been executed on this
_____________, 1997, effective for all purposes as provided above.




                                    STERLING CHEMICALS, INC.


                                    By:
                                       ---------------------
                                    Name:
                                         -------------------
                                    Title:
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