<PAGE>
                                                                    EXHIBIT 10.1

                             SIXTH AMENDMENT TO THE
                            STERLING CHEMICALS, INC.
                           SIXTH AMENDED AND RESTATED
                           SAVINGS AND INVESTMENT PLAN


                                   WITNESSETH:


         WHEREAS, Sterling Chemicals, Inc. (the "Employer") presently maintains
the Sterling Chemicals, Inc. Sixth Amended and Restated Savings and Investment
Plan (the "Plan"); and

         WHEREAS, the Employer, pursuant to Section 16.01 of the Plan, has the
right to amend the Plan from time to time subject to certain limitations.

         NOW, THEREFORE, the Plan is hereby amended in the following manner:

         1. Effective as of the date of the execution hereof, Section 10.03(a)
of the Plan is hereby amended by adding the following paragraphs to read as
follows:

                  Participants who are terminated under a formal reduction in
         workforce or layoff program are allowed to continue to make loan
         repayments and are not subject to the involuntary cash out described in
         the paragraph above in this Section 10.03(a). However, once a
         Participant who is terminated under a formal reduction in workforce or
         layoff program defaults on a plan loan (as determined under Section
         12.16 of the Plan) or fully repays all plan loans, and such
         Participant's Account balance is $5,000 or less at that time, then the
         Plan shall distribute the Participant's entire vested Account balance
         (in accordance with Section 12.13) as soon as practicable after such
         Participant's Settlement Date (after all adjustments, if any, then
         required under this Plan have been made).

                  Notwithstanding anything in this Section 10.03 of the Plan to
         the contrary, the value of a Participant's vested Account balances
         shall be determined by including that portion of the Account balance
         that is attributable to rollover contributions (and earnings allocable
         thereto) within the meaning of sections 402(c), 403(a)(4), 403(b)(8),
         408(d)(3)(A)(ii), and 457(e)(16) of the Code.

         2. Effective as of the date of the execution hereof, Section 12.03 of
the Plan is hereby amended by adding the following sentence to read as follows:

         Additionally, Participants who are on a paid leave of absence from the
         Employer are eligible to submit loan applications to obtain a loan.
         Notwithstanding anything in this Article XII to the contrary,
         Participants who are on unpaid leave of absence or military leave of
         absence are not eligible to submit loan applications to obtain a new
         loan.

<PAGE>


         3. Effective as of the date of the execution hereof, Section 12.07 of
the Plan is hereby amended by adding the following paragraph to read as follows:

                  Notwithstanding anything in this Section 12.07 to the
         contrary, consistent with the requirements under the Servicemembers
         Civil Relief Act, any loan outstanding at the time a Participant enters
         military service (as defined under the Servicemembers Civil Relief Act)
         shall be charged a rate of interest of no more than 6 percent
         compounded annually during such period of military service, which shall
         end on the date on which the Participant is released from military
         service or dies while in military service. To obtain this 6 percent
         rate, the Participant must provide the plan with written notice and a
         copy of the military orders calling the Participant to military
         service. Upon receipt of written notice and a copy of orders calling a
         Participant to military service, the Plan shall reduce the rate of
         interest on the Participant's loan(s) to 6 percent effective as of the
         date on which the Participant is called to military service.

         4. Effective as of the date of the execution hereof, the last sentence
of Section 12.08(a) of the Plan is hereby amended in its entirety to read as
follows:

         The period of repayment for any loan shall be determined by mutual
         agreement between the Committee, or its delegate, and the Participant,
         but such period shall in no event exceed 60 months (plus the period
         that such Participant was on a leave of absence due to performing
         service in the uniformed services as provided for under Section 12.19).

         5. Effective as of the date of the execution hereof, the first sentence
of Section 12.14 of the Plan is hereby amended in its entirety to read as
follows:

         Except as provided under Section 12.19, in the event that any principal
         or interest on any loan remains outstanding at the end of 60 months,
         the Committee or its delegate shall declare the remaining unpaid loan
         balance to be a taxable distribution from this Plan for purposes of
         Section 72(p) of the Code.

         6. Effective as of the date of the execution hereof, Section 12.19 of
the Plan is hereby added in its entirety to read as follows:

                  Section 12.19. Performing Service in the Uniformed Services.
         Notwithstanding anything in this Section 12.19 to the contrary, this
         Article XII shall be applied in accordance with the requirements under
         Section 414(u) of the Code. If the Plan suspends repayments for any
         part of a period during which the Participant is performing service in
         the uniformed services (as defined in Chapter 43 of Title 38 of the
         United States Code), whether or not qualified military service (as
         defined under Section 414(u)(5) of the Code), the suspension will not
         cause the loan to be deemed distributed under Section 72(p) of the
         Code. However, the loan will not satisfy the repayment term requirement
         and level amortization


                                       2
<PAGE>


         requirement of Section 72(p)(2) of the Code unless the loan repayments
         resume upon the completion of such period of performing service in the
         uniformed services and the loan is repaid thereafter by amortization in
         substantially level installments over a period that ends not later than
         the latest permissible term of the loan (which shall include the
         original term of the loan plus the period that such Participant was on
         a leave of absence due to performing service in the uniformed
         services).

                  Upon resuming active employment after performing service in
         the uniformed services ends, the Participant shall have the following
         option with respect to the repayment of his or her outstanding loan
         balance (which shall include interest that accrued during such period
         of the military leave of absence and shall resume upon the
         Participant's completion of performing service in the uniformed
         services):

                           (a) continue the monthly installments with respect to
                  the loan in the same amount as required prior to the military
                  leave of absence and pay the full balance remaining at the end
                  of the term of the loan; or

                           (b) continue the monthly installments with respect to
                  the loan in an increased amount to include the interest that
                  accrued during the period that the Participant was on a
                  military leave of absence, which shall be amortized in
                  substantially level installments over the remaining term of
                  the loan.

         If the Participant who was on a military leave of absence fails to
         elect either option (a) or (b) above within 15 days after resuming
         active employment, then the Participant shall continue the monthly
         installments for his or her loan under option (b) above.



         IN WITNESS WHEREOF, the Employer has executed this Sixth Amendment to
the Sterling Chemicals, Inc. Sixth Amended and Restated Savings and Investment
Plan on the _____ day of ___________, 2004.


                                           STERLING CHEMICALS, INC.


                                           By:
                                                 -------------------------------

                                           Name:
                                                 -------------------------------

                                           Title:
                                                 -------------------------------


                                       3