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                                   Exhibit 4.8

THE SECURITIES REPRESENTED BY THIS CERTIFICATE, AND THE SECURITIES ISSUED UPON
EXERCISE HEREOF, MAY NOT BE OFFERED FOR SALE, SOLD OR OTHERWISE TRANSFERRED
EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT FILED UNDER THE
SECURITIES ACT OF 1933 (THE "ACT"), OR PURSUANT TO AN EXEMPTION FROM
REGISTRATION UNDER THE ACT WHICH SHALL BE ESTABLISHED TO THE SATISFACTION OF THE
COMPANY.

             Void after 3:30 P.M., Denver Time, on January 31, 2006

                                                             Warrant to Purchase
                                                             ____________ Shares
                                                             of Common Stock

                   WARRANT TO PURCHASE SHARES OF COMMON STOCK

                                       OF

                                  RENTECH, INC.

     This Is to Certify That, FOR VALUE RECEIVED, ______________________________
or permitted assigns ("Holder"), is entitled to purchase, subject to the
provisions of this Warrant, from RENTECH, INC., a Colorado corporation
("Company"), at any time not later than 3:30 P.M., Denver time, on January 31,
2006, (the "Expiration Date") One Hundred Twenty-Six Thousand Two Hundred Fifty
(126,250) shares of common stock, having $.01 par value per share, of the
Company ("Common Stock") at an exercise price, subject to adjustment as set
forth below, of $1.00 per share. The number of shares of Common Stock to be
received upon the exercise of this Warrant and the price to be paid for a share
of Common Stock are subject to adjustment from time to time as hereinafter set
forth. The shares of the Common Stock deliverable upon such exercise, and as
adjusted from time to time, are hereinafter sometimes referred to as "Warrant
Stock" and the exercise price of a share of Common Stock in effect at any time
and as adjusted from time to time is hereinafter sometimes referred to as the
"Exercise Price."

     1. Exercise of Warrant. Subject to the provisions of Section 4 hereof, this
Warrant may be exercised in whole or in part at any time or from time to time
not later than 3:30 P.M., Denver Time, on January 31, 2006, or if that date
falls on a day on which banking institutions are authorized by law to close,
then on the next succeeding day which shall not be such a day, by presentation
and surrender hereof to the Company with the Purchase Form annexed hereto duly
executed and accompanied by payment of the Exercise Price for the number of
shares specified in such form, together with all federal and state taxes
applicable upon such exercise. If this Warrant should be exercised in part only,
the Company shall, upon surrender of this Warrant for cancellation, execute and
deliver a new Warrant evidencing the right of the Holder to purchase the balance
of the shares purchasable hereunder. Upon receipt by the Company of this Warrant
at the office or agency of the Company, in proper form for exercise, the Holder
shall be deemed to be the holder of record of the shares of Common Stock
issuable upon such exercise, notwithstanding that the stock transfer books of
the Company shall then be closed or that certificates representing such
securities shall not then be actually delivered to the Holder. The Exercise
Price shall be paid in immediately available funds by cashier's check or by wire
transfer.

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     2. Reservation of Shares. The Company hereby agrees that at all times there
shall be reserved for issuance and delivery, upon exercise of this Warrant, such
number of shares of its Common Stock as shall be required for issuance or
delivery upon exercise of this Warrant.

     3. Fractional Shares. No fractional shares or scrip representing fractional
shares shall be issued upon any exercise of this Warrant. With respect to any
fraction of a share called for upon any exercise hereof, the Company shall pay
to the Holder an amount in cash equal to such fraction multiplied by the current
market value of such fractional share, determined as follows:

          (a) If the Common Stock is listed on a national securities exchange or
     admitted to unlisted trading privileges on such exchange, the current value
     shall be the last reported sale price of the Common Stock on the composite
     tape of such exchange on the last trading day prior to the date of exercise
     of this Warrant, or if no such sale is made on such day, the average
     closing bid and asked prices for such day on the composite tape of the
     exchange; or

          (b) If the Common Stock is not so listed or admitted to unlisted
     trading privileges, the current value shall be the mean of the last
     reported bid and asked prices reported by the National Association of
     Securities Dealers Quotation System (or, if not so quoted on NASDAQ, by the
     National Quotation Bureau, Inc.) on the last trading day prior to the date
     of the exercise of this Warrant; or

          (c) If the Common Stock is not so listed or admitted to unlisted
     trading privileges and bid and asked prices are not so reported, the
     current value shall be an amount, not less than book value, determined in
     such reasonable manner as may be prescribed by the Board of Directors of
     the Company, such determination to be final and binding on the Holder.

     4. Exchange, Assignment or Loss of Warrant. This Warrant is not assignable
except to employees of the original Holder who are registered sales
representatives and who are licensed through a licensed securities broker-dealer
and who directly participated in the Company's private placement for which this
Warrant was issued. This Warrant is assignable to permitted assignees and
exchangeable, without expense, at the option of the Holder, upon presentation
and surrender hereof to the Company or at the office of its stock transfer
agent, if any, for other Warrants of different denominations entitling the
holder thereof to purchase in the aggregate the same number of shares of Common
Stock purchasable hereunder. Any such assignment shall be made by surrender of
this Warrant to the Company or at the office of its stock transfer agent, if
any, with the Assignment Form annexed hereto duly executed and funds sufficient
to pay any transfer tax; whereupon the Company shall, without charge, execute
and deliver a new Warrant in the name of the permitted assignee named in such
instrument of assignment. Upon any permitted assignment or exchange, this
Warrant promptly shall be canceled. This Warrant may be divided or combined with
other Warrants which carry the same rights upon presentation hereof at the
office of the Company or at the office of its stock transfer agent, if any,
together with a written notice specifying the denominations in which new
Warrants are to be issued and signed by the Holder hereof. The term "Warrant" as
used herein includes any Warrants issued in substitution for or replacement of
this Warrant, or into which this Warrant may be divided or exchanged. Upon
receipt by the Company of evidence satisfactory to it of the loss, theft,
destruction or mutilation of this Warrant, and (in the case of loss, theft or
destruction) of reasonably satisfactory indemnification including a surety bond,
and upon surrender and cancellation of this Warrant, if mutilated, the Company
will execute and deliver a new Warrant of like tenor and date. Any such new
Warrant executed and delivered shall constitute an additional contractual
obligation on the part of the Company, whether or not this Warrant so lost,
stolen, destroyed, or mutilated, and shall be at any time enforceable by a
Holder.

     5. Rights of the Holder. The Holder shall not, by virtue hereof, be
entitled to any rights of a shareholder of the Company, either at law or equity,
and the rights of the Holder are limited to

<PAGE>

those expressed in this Warrant and are not enforceable against the Company
except to the extent set forth herein.

     6. Anti-Dilution Provisions.

        (a) Stock Splits and Stock Dividends. Anything in this Section 6 to the
     contrary notwithstanding, in case the Company shall at any time issue
     Common Stock or securities convertible into or exercisable or exchangeable
     for Common Stock by way of dividend or other distribution on any stock of
     the Company or subdivide or combine the outstanding shares of Common Stock,
     the Exercise Price shall be proportionately decreased in the case of such
     issuance (on the day following the date fixed for determining shareholders
     entitled to receive such dividend or other distribution) or decreased in
     the case of such subdivision or increased in the case of such combination
     (on the date that such subdivision or combination shall become effective);
     provided, however, that the Exercise Price shall never be less than the par
     value per share of Common Stock.

        (b) Number of Shares Adjusted. Upon any adjustment of the Exercise
     Price, the holder of this Warrant shall thereafter (until another such
     adjustment) be entitled to purchase, at the new Exercise Price, the number
     of Shares, calculated to the nearest full share, obtained by multiplying
     the number of shares of Common Stock initially issuable upon exercise of
     this Warrant by the Exercise Price in effect on the date hereof and
     dividing the product so obtained by the new Exercise Price.

        (c) Common Stock Defined. Whenever reference is made in this Section 6
     to the issue or sale of shares of Common Stock, the term "Common Stock"
     shall mean the Common Stock of the Company of the class authorized as of
     the date hereof and any other class of stock ranking on a parity with such
     Common Stock. However, subject to the provisions of Section 9 hereof,
     shares issuable upon exercise hereof shall include only shares of the class
     designated as Common Stock of the Company as of the date hereof.

        (d) Adjustment of Number of Shares Upon Issuance of Common Stock. If and
     whenever the Company issues or sells any Common Stock for a consideration
     per share less than the Exercise Price per share at the time of such issue
     or sale, then forthwith upon such issue or sale, the number of shares of
     Warrant Stock will be increased by multiplying the number of shares of
     Warrant Stock by a fraction, (A) the numerator of which is the Exercise
     Price per share and (B) the denominator of which is the amount determined
     by dividing (a) the sum of (1) the product derived by multiplying the
     Exercise Price times the number of shares of Common Stock outstanding
     immediately prior to such issue or sale, plus (2) the aggregate
     consideration, if any, received by the Company upon such issue or sale, by
     (b) the number of shares of common Stock outstanding immediately after such
     issue or sale.

     7. Officer's Certificate. Upon request by the Holder, and if the Exercise
Price is adjusted as required by the provisions of Section 6 hereof, the Company
shall forthwith file in the custody of its Secretary or an Assistant Secretary
at its principal office, and with its stock transfer agent, if any, an officer's
certificate showing the adjusted Exercise Price determined as herein provided
and setting forth in reasonable detail the facts requiring such adjustment and
the calculation thereof. Each such officer's certificate shall be made available
at all reasonable times for inspection by the Holder and the Company shall, upon
request after each such adjustment, mail a copy of such certificate to the
Holder.

     8. Notice to Holders. If, prior to the expiration of this Warrant either by
its terms or by its exercise in full, any of the following shall occur:

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          (a) the Company shall declare a dividend or authorize any other
          distribution on its Common Stock; or

          (b) the Company shall authorize the granting to the shareholders of
          its Common Stock of rights to subscribe for or purchase any securities
          or any other similar rights; or

          (c) any reclassification, reorganization or similar change of the
          Common Stock, or any consolidation or merger to which the Company is a
          party, or the sale, lease, or exchange of any signification portion of
          the assets of the Company; or

          (d) the voluntary or involuntary dissolution, liquidation or winding
          up of the Company; or

          (e) any purchase, retirement or redemption by the Company of its
          Common Stock;

     then, and in any such case, the Company shall deliver to the Holder or
     Holders written notice thereof at least 30 days prior to the earliest
     applicable date specified below with respect to which notice is to be
     given, which notice shall state the following:

          (f) the date on which a record is to be taken for the purpose of such
          dividend, distribution or rights, or, if a record is not to be taken,
          the date as of which the shareholders of Common Stock of record to be
          entitled to such dividend, distribution or rights are to be
          determined;

          (g) the date on which such reclassification, reorganization,
          consolidation, merger, sale, transfer, dissolution, liquidation,
          winding up or purchase, retirement or redemption is expected to become
          effective, and the date, if any, as of which the Company's
          shareholders of Common Stock of record shall be entitled to exchange
          their Common Stock for securities or other property deliverable upon
          such reclassification, reorganization, consolidation, merger, sale,
          transfer, dissolution, liquidation, winding up, purchase, retirement
          or redemption; and

          (h) if any matters referred to in the foregoing clauses (a) and (b)
          are to be voted upon by shareholders of Common Stock, the date as of
          which those shareholders to be entitled to vote are to be determined.

          9.  Reclassification, Reorganization or Merger. In case of any
     reclassification, capital reorganization or other change of outstanding
     shares of Common Stock of the Company (other than a change in par value, or
     from par value to no par value, or as a result of an issuance of Common
     Stock by way of dividend or other distribution or of a subdivision or
     combination), or in case of any consolidation or merger of the Company with
     or into another corporation (other than a merger with a subsidiary in which
     merger the Company is the continuing corporation and which does not result
     in any reclassification, capital reorganization or other change of
     outstanding shares of Common Stock of the class issuable upon exercise of
     this Warrant) or in case of any sale or conveyance to another corporation
     of the property of the Company as an entirety or substantially as an
     entirety, the Company shall cause effective provision to be made so that
     the Holder shall have the right thereafter, by exercising this Warrant, to
     purchase the kind and amount of shares of stock and other securities and
     property receivable upon such reclassification, capital reorganization or
     other change, consolidation, merger, sale or conveyance as if the Holder
     had exercised this Warrant prior to such transaction. Any such provision
     shall include provision for adjustments which shall be as nearly equivalent
     as may be practicable to the adjustments provided for in this Warrant. A
     copy of such provision shall be furnished to the holder(s) of Warrants
     within ten days after execution of the appropriate agreement pertaining to
     same and, in any event, prior to any consolidation, merger, sale or
     conveyance subject to the provisions of this Section 9. The foregoing
     provisions of this Section 9 shall similarly apply to successive
     reclassifications, capital reorganizations and changes of shares of Common
     Stock and to successive consolidations, mergers, sales or conveyances.

<PAGE>

          10. Dissolution. If, at any time prior to the expiration of this
     Warrant and prior to the exercise thereof, any dissolution, liquidation or
     winding up of the Company shall be proposed, the Company shall cause at
     least 30 days' notice to be mailed by certified mail to the registered
     Holder of this Warrant Certificate at the Holder's address as it appears on
     the books of the Company. Such notice shall specify the date as of which
     holders of record of Common Stock shall participate in any distribution or
     shall be entitled to exchange their Common Stock for securities or other
     property, deliverable upon such dissolution, liquidation or winding up, as
     the case may be; to the end that, during such period of 30 days, the Holder
     of this Warrant may exercise this Warrant and purchase Common Stock (or
     other stock substituted therefor as hereinbefore provided) and be entitled
     in respect of shares so purchased to all of the rights of the other holders
     of Common Stock of the Company. In case of a dissolution, liquidation or
     winding up of the Company, all purchase rights under this Warrant shall
     terminate at the close of business on the date as of which holders of
     record of the Common Stock shall be entitled to participate in a
     distribution of the assets of the Company in connection with such
     dissolution, liquidation or winding up (provided that in no event shall
     said date be less than 30 days after completion of service by certified
     mail of notice as aforesaid). Any Warrant not exercised prior to such time
     shall be void and no rights shall exist thereunder. In any such case of
     termination of purchase rights, a statement thereof shall be included in
     the notice provided for herein.

          11. Spin-Offs. In the event the Company spins-off a subsidiary or
     stock held in another corporation as an investment by distributing to the
     shareholders of the Company, as a dividend or otherwise, the stock of the
     subsidiary or other corporation, the Company shall reserve, for the life of
     the Warrant, shares of the subsidiary or other corporation to be delivered
     to the holders of the Warrants upon exercise to the same extent as if they
     were owners of record of the Warrant Stock on the record date for payment
     of the shares of the subsidiary or other corporation.

          12. Rights.

              (a) Piggy-Back Registration. Subject to Section 12(i) below, if at
          any time during the two years following the date of this Warrant, the
          Company proposes to register any of its Common Stock under the Act in
          connection with the public offering of such securities solely for cash
          on a form that would also permit the registration of the Common Stock
          of the Holders that they acquire through exercise of this Warrant, the
          Company shall, each such time, promptly give each Holder written
          notice of such determination. Upon the written request of any Holder
          given within 20 days after mailing of any such notice by the Company,
          the Company shall use its best efforts to cause to be registered under
          the Act all of such Common Stock acquired through exercise of this
          Warrant that each such Holder has requested to be registered.

              (b) Obligations of the Company. Whenever required to use its best
          efforts to effect the registration of any Common Stock, the Company
          shall, as expeditiously as reasonably possible:

                  (A) Prepare and file with the Securities and Exchange
              Commission ("SEC") a registration statement with respect to such
              Warrant Stock and use its best efforts to cause such registration
              statement to become and remain effective; provided, however, that
              in connection with any proposed registration intended to permit an
              offering of any securities from time to time (i.e., a so-called
              "shelf registration"), the Company shall in no event be obligated
              to cause any such registration to remain effective for more than
              one year.

                  (B) Prepare and file with the SEC such amendments and
              supplements to such registration statement and the prospectus used
              in connection with such

<PAGE>

          registration statement as may be necessary to comply with the
          provisions of the Act with respect to the disposition of all
          securities covered by such registration statement.

               (C) Furnish to the Holders such numbers of copies of a
          prospectus, including a preliminary prospectus, in conformity with the
          requirements of the Act, and such other documents as they may
          reasonably request in order to facilitate the disposition of Warrant
          Stock owned by them.

               (D) Use its best efforts to register and qualify the securities
          covered by such registration statement under such other securities or
          blue-sky laws of such jurisdictions as shall be reasonably appropriate
          for the distribution of the securities covered by the registration
          statement, provided that the Company shall not be required in
          connection therewith or as a condition thereto to qualify to do
          business or to file a general consent to service of process in any
          such states or jurisdictions, and further provided that (anything in
          this Section (l) to the contrary notwithstanding with respect to the
          bearing of expenses) if any jurisdiction in which the securities shall
          be qualified shall require that expenses incurred in connection with
          the qualification of the securities in that jurisdiction be borne by
          selling shareholders pro rata, to the extent required by such
          jurisdiction.

          (c)  Furnish Information. It shall be a condition precedent to the
     obligations of the Company to take any action that the Holders shall
     furnish to the Company such information regarding them, the Warrant Stock
     held by them, and the intended method of disposition of such securities as
     the Company shall reasonably request and as shall be required in connection
     with the action to be taken by the Company.

          (d)  Company Registration Expenses. In the case of any registration
     effected pursuant to Section (12)(a), the Company shall bear any additional
     registration and qualification fees and expenses (excluding underwriters'
     discounts, commissions and expenses), and any additional costs and
     disbursements of counsel for the Company that result from the inclusion of
     securities held by the Holders in such registration; provided, however,
     that if any such cost or expense is attributable solely to one selling
     Holder and does not constitute a normal cost or expense of such a
     registration, such cost or expense shall be paid by that selling Holder. In
     addition, each selling Holder shall bear the fees and costs of its own
     counsel.

          (e)  Underwriting Requirements. In connection with any offering
     involving an underwriting of shares of Common Stock being issued by the
     Company or being sold by persons other than the Holders exercising
     piggy-back registration rights (the "Initial Sellers"), the Company shall
     not be required under Section 12(a) to include any of the Holders' Warrant
     Stock in such underwriting unless they accept the terms of the underwriting
     as agreed upon between the Company or the Initial Sellers and the
     underwriters selected by it or them, and then only in such quantity as will
     not, in the written opinion of the underwriters, jeopardize the success of
     the offering by the Company or by the Initial Sellers. If the total amount
     of securities that all Holders request to be included in such offering
     exceeds the amount of securities that the underwriters reasonably believe
     compatible with the success of the offering, the Company shall only be
     required to include in the offering so many of the securities of the
     selling Holders as the underwriters believe will not jeopardize the success
     of the offering (the securities so included to be apportioned pro rata
     among the selling Holders according to the total amount of securities owned
     by said selling Holders, or in such other proportions as shall mutually be
     agreed to by such selling Holders), provided that no such reduction shall
     be made with respect to any securities offered by the Company or the
     Initial Sellers for its or their own account.

<PAGE>

          (f)  Delay of Registration. No Holder shall have any right to take any
     action to restrain, enjoin, or otherwise delay any registration as the
     result of any controversy that might arise with respect to the
     interpretation or implementation of this Section 12.

          (g)  Indemnification. In the event any Common Stock is included in a
     registration statement:

               (A) To the extent permitted by law, the Company will indemnify
          and hold harmless each Holder requesting or joining in a registration,
          any underwriter (as defined in the Act) for it, and each such person,
          if any, who controls such Holder or underwriter within the meaning of
          the Act, against any losses, claims, damages, or liabilities, joint or
          several, to which they may become subject under the Act or otherwise,
          insofar as such losses, claims, damages, or liabilities (or actions in
          respect thereof) arise out of or are based on any untrue or alleged
          untrue statement of any material fact contained in such registration
          statement, including any preliminary prospectus or final prospectus
          contained therein or any amendments or supplements thereto, or arise
          out of or are based upon the omission or alleged omission to state
          therein a material fact required to be stated therein, or necessary to
          make the statements therein not misleading; and will reimburse each
          such Holder, such underwriter, or controlling person for any legal or
          other expenses reasonably incurred by them in connection with
          investigating or defending any such loss, claim, damage, liability, or
          action; provided, however, that the indemnity agreement contained in
          this Section 12 (g)(A) shall not apply to amounts paid in settlement
          of any such loss, claim, damage, liability, or action if such
          settlement is effected without the consent of the Company (which
          consent shall not be unreasonably withheld) nor shall the Company be
          liable in any such case for any such loss, claim, damage, liability,
          or action to the extent that it arises out of or is based upon an
          untrue statement or alleged untrue statement or omission or alleged
          omission made in connection with such registration statement,
          preliminary prospectus, final prospectus, or amendments or supplements
          thereto, in reliance upon and in conformity with written information
          furnished expressly for use in connection with such registration by
          any such Holder, underwriter, or controlling person.

               (B) To the extent permitted by law, each Holder requesting or
          joining in a registration will indemnify and hold harmless the
          Company, each of its directors, each of its officers who have signed
          the registration statement, each person, if any, who controls the
          Company within the meaning of the Act, and each agent and any
          underwriter for the Company (within the meaning of the Act) against
          any losses, claims, damages, or liabilities to which the Company or
          any such director, officer, controlling person, agent, or underwriter
          may become subject, under the Act or otherwise, insofar as such
          losses, claims, damages, or liabilities (or actions in respect
          thereto) arise out of or are based upon any untrue statement or
          alleged untrue statement of any material fact contained in such
          registration statement, including any preliminary prospectus or final
          prospectus contained therein or any amendments or supplements thereto,
          or arise out of or are based upon the omission or alleged omission to
          state therein a material fact required to be stated therein or
          necessary to make the statements therein not misleading, in each case
          to the extent, but only to the extent, that such untrue statement or
          alleged untrue statement or omission or alleged omission was made in
          such registration statement, preliminary or final prospectus, or
          amendments or supplements thereto, in reliance upon and in conformity
          with written information furnished by such Holder expressly for use in
          connection with such registration; and each such Holder will reimburse
          any legal or other expenses

<PAGE>

          reasonably incurred by the Company or any such director, officer,
          controlling person, agent, or underwriter in connection with
          investigating or defending any such loss, claim, damage, liability, or
          action; provided, however, that the indemnity agreement contained in
          this Section 12 (g)(B) shall not apply to amounts paid in settlement
          of any such loss, claim, damage, liability, or action if such
          settlement is effected without the consent of such Holder (which
          consent shall not be unreasonably withheld).

               (C) Promptly after receipt by an indemnified party under this
          Section 12(g) of notice of the commencement of any action, such
          indemnified party will, if a claim in respect thereof is to be made
          against any indemnifying party under this paragraph, notify the
          indemnifying party in writing of the commencement thereof and the
          indemnifying party shall have the right to participate in, and, to the
          extent the indemnifying party so desires, jointly with any other
          indemnifying party similarly noticed, to assume the defense thereof
          with counsel mutually satisfactory to the parties. The failure to
          notify an indemnifying party promptly of the commencement of any such
          action, if prejudicial to his ability to defend such action, shall
          relieve such indemnifying party of any liability to the indemnified
          party under this paragraph, but the omission to so notify the
          indemnifying party will not relieve him of any liability that he may
          have to any indemnified party otherwise than under this paragraph.

          (h) Termination of the Company's Obligations. The Company shall have
     no obligations pursuant to this Section 12 more than three years after the
     Expiration Date of this Agreement.

          (i) Lockup Agreement. In consideration for the Company agreeing to its
     obligations under this Section 12, each Holder agrees in connection with
     any registration of the Company's securities that, upon the request of the
     Company or the underwriters managing any underwritten offering of the
     Company's securities, not to sell, make any short sale of, loan, grant any
     option for the purchase of, or otherwise dispose of any Warrant Stock
     (other than those included in the registration) without the prior written
     consent of the Company or such underwriters, as the case may be, for such
     period of time (not to exceed 30 days from the effective date of such
     registration) as the Company or the underwriters may specify.

          (j) Notice. Any notices or certificates by the Company to the Holder
     and by the Holder to the Company shall be deemed delivered if in writing
     and delivered personally (including by telex, telecopier, telegram or other
     acknowledged receipt) or three business days following deposit in the
     United States mails, sent by registered or certified mail, return receipt
     requested, addressed as follows:

          Holder:

          Company:   Rentech, Inc.
                     1331 17/th/ Street, Suite 720
                     Denver, CO 80202
                     Attention: Chief Operating Officer

Any person may change the address for the giving of notice by providing notice
in accordance with these provisions. The change in notice shall be effective
five (5) business days thereafter.

<PAGE>

     13.  Amendments and Waivers. Any term, condition or provision of this
Warrant may be amended and the observance thereof may be waived (either
generally or in a particular instance and either retroactively or
prospectively), with the written consent of the Company and the Holders.

     14.  Entire Agreement. This Warrant constitutes the entire agreement among
the parties thereto and supersedes any and all prior agreements whether written
or oral regarding the subject matter hereof.

     15.  Transfer to Comply with the Securities Act of 1933.

          (a) This Warrant or the Warrant Stock or any other security issued or
     issuable upon exercise of this Warrant may not be offered or sold except in
     conformity with the Securities Act of 1933, as amended, and then only
     against receipt of an agreement of such person to whom such offer of sale
     is made to comply with the provisions of this Section 15 with respect to
     any resale or other disposition of such securities.

          (b) Before this Warrant may be sold, transferred, or assigned to a
     permitted assignee by the Holder, the Holder must notify the Company in
     writing at least 30 days prior to any such transfer. The Company shall the
     first right of refusal to repurchase the Warrant for an amount not less
     than the amount offered by any third party.

          (c) The Company may cause the following legend to be set forth on each
     certificate representing Warrant Stock or any other security issued or
     issuable upon exercise of this Warrant not theretofore distributed to the
     public or sold to underwriters for distribution to the public pursuant to
     Section (l) hereof, unless counsel for the Company is of the opinion as to
     any such certificate that such legend is unnecessary:

          The securities represented by this certificate may not be offered for
          sale, sold or otherwise transferred except pursuant to an effective
          registration statement made under the Securities Act of 1933 (the
          "Act"), or pursuant to an exemption from registration under the Act
          the availability of which is to be established to the satisfaction of
          the Company.

     16.  Applicable Law. This Warrant shall be governed by, and construed in
accordance with, the laws of the state of Colorado.

                                   RENTECH, INC.

ATTEST:

_______________________________    By:  _____________________________________
Ronald C. Butz, Secretary                                 Dennis L. Yakobson,
                                         President

                                   Date: January 31, 2003