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 Amendment No. Two to Registration Statement No. 333-35571 of Rentech, Inc. on Form S-3 of our report dated November 26, 1997 relating to the consolidated financial statements (which contained an explanatory paragraph relative to the going concern uncertainty) appearing in the Annual Report on Form 10-KSB/A of Rentech, Inc. for the year ended September 30, 1997 and for the nine months ended September 30, 1996, and to the reference to us under the heading "Experts" in the Prospectus, which is part of such Registration Statement. BDO Seidman, LLP January 19, 1998 Denver, Colorado