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                                                                 EXHIBIT 10.51
AMENDMENT NO. 1 TO CREDIT AGREEMENT

         AMENDMENT dated as of May 15, 2000 (the "AMENDMENT") to the Revolving
Credit and Guaranty Agreement dated as of May 4, 2000 (the "CREDIT AGREEMENT")
among LAROCHE INDUSTRIES INC. (the "BORROWER"), LAROCHE FORTIER INC. (the
"GUARANTOR"), the LENDERS party thereto (the "LENDERS") and THE CHASE MANHATTAN
BANK, as Agent (the "AGENT").

                              W I T N E S S E T H :

         WHEREAS, the Borrower has requested that the Lenders agree to extend
the date provided for the delivery of certain documents; and

         WHEREAS, subject to the terms and conditions set forth herein, the
Lenders have agreed to so agree as provided for herein;

         NOW, THEREFORE, the parties hereto agree as follows:

         SECTION 1. DEFINED TERMS; REFERENCES. Unless otherwise specifically
defined herein, each term used herein that is defined in the Credit Agreement
has the meaning assigned to such term in the Credit Agreement. Each reference to
"hereof", "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Credit Agreement shall, from and after May 15, 2000, refer to
the Credit Agreement as amended hereby.

         SECTION 2. SECTION 10.15. Section 10.15 of the Credit Agreement is
amended by replacing the phrase "May 15, 2000" with the phrase "May 31, 2000 or
such later date to which the Agent shall, in its sole discretion, agree in
writing".

         SECTION 3. REPRESENTATIONS AND WARRANTIES. The Borrower represents and
warrants that, on and as of May 15, 2000 and after giving effect to this
Amendment, (i) the representations and warranties set forth in the Loan
Documents are true and correct and (ii) no Default has occurred and is
continuing.

         SECTION 4. GOVERNING LAW. This Amendment shall be governed by and
construed in accordance with the laws of the State of New York.

         SECTION 5. COUNTERPARTS. This Amendment may be signed in any number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

         SECTION 6. EFFECTIVENESS. This Amendment shall become effective on the
date on which the Agent shall have received from each of the Borrower and the
Required Lenders a counterpart hereof signed by such party or facsimile or other


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written confirmation (in form satisfactory to the Agent) that such party has
signed a counterpart hereof.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of May 15, 2000.

                                            LAROCHE INDUSTRIES INC.


                                            By:_______________________________
                                               Name:
                                               Title:

                                            LAROCHE FORTIER INC.


                                            By:_______________________________
                                               Name:
                                               Title:


                                            THE CHASE MANHATTAN BANK


                                            By:_______________________________
                                               Name:
                                               Title:


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