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                                                                    Exhibit 31.1

I, Richard K. Crump, certify that:

      1.    I have reviewed this quarterly report on Form 10-Q of Sterling
            Chemicals, Inc.;

      2.    Based on my knowledge, this report does not contain any untrue
            statement of a material fact or omit to state a material fact
            necessary to make the statements made, in light of the circumstances
            under which such statements were made, not misleading with respect
            to the period covered by this report;

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this report, fairly present in all material
            respects the financial condition, results of operations and cash
            flows of the registrant as of, and for, the periods presented in
            this report;

      4.    The registrant's other certifying officer(s) and I are responsible
            for establishing and maintaining disclosure controls and procedures
            (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
            registrant and have:

                (a) Designed such disclosure controls and procedures, or caused
                such disclosure controls and procedures to be designed under our
                supervision, to ensure that material information relating to the
                registrant, including its consolidated subsidiaries, is made
                known to us by others within those entities, particularly during
                the period in which this report is being prepared;

                (b) Evaluated the effectiveness of the registrant's disclosure
                controls and procedures and presented in this report our
                conclusions about the effectiveness of the disclosure controls
                and procedures, as of the end of the period covered by this
                report based on such evaluation; and

                (c) Disclosed in this report any change in the registrant's
                internal control over financial reporting that occurred during
                the registrant's most recent fiscal quarter (the registrant's
                fourth fiscal quarter in the case of an annual report) that has
                materially affected, or is reasonably likely to materially
                affect, the registrant's internal control over financial
                reporting; and

      5.    The registrant's other certifying officer(s) and I have disclosed,
            based on our most recent evaluation of internal control over
            financial reporting, to the registrant's auditors and the audit
            committee of the registrant's board of directors (or persons
            performing the equivalent functions):

                (a) All significant deficiencies and material weaknesses in the
                design or operation of internal control over financial reporting
                which are reasonably likely to adversely affect the registrant's
                ability to record, process, summarize and report financial
                information; and

                (b) Any fraud, whether or not material, that involves management
                or other employees who have a significant role in the
                registrant's internal control over financial reporting.

Date: August 12, 2003


                  /s/ RICHARD K. CRUMP
                  --------------------------------------------
                  Richard K. Crump

                  President and Chief Executive Officer