Exhibit 23.1 CONSENT OF INDEPENDENT CERTIFIED PUBLIC ACCOUNTANTS Rentech, Inc. 1331 17th Street, Suite 720 Denver, CO 80202 We consent to the incorporation by reference in Registration Statement Nos. 333-39334, 333-34890, 333-47317 and Post-Effective Amendment No. One to Registration Statement No. 333-47317, which was approved as Registration Statement No. 333-58529, of Rentech, Inc. on Form S-3, and in Registration Statement Nos. 333-95537, 033-90250, and 333-46003 of Rentech, Inc. on Form S-8, of our report dated December 12, 2001 appearing in the Annual Report on Form 10-K/A of Rentech, Inc. for the year ended September 30, 2001. We also consent to the reference to us under the heading "Experts" in the Prospectuses, which are a part of the Registration Statements. /s/ BDO Seidman, LLP - ---------------------- BDO Seidman, LLP October 23, 2002 Dallas, Texas