UNIT PURCHASE WARRANT To Purchase Class A Limited Liability Company Units of BLACKHAWK BIOFUELS, LLC

EXHIBIT 4.11

THIS WARRANT, AND ANY LIMITED LIABILITY COMPANY UNITS ACQUIRED UPON THE EXERCISE OF THIS WARRANT, HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ ACT ”) OR ANY OTHER APPLICABLE SECURITIES LAWS. THIS WARRANT HAS BEEN ACQUIRED FOR INVESTMENT AND NEITHER THIS WARRANT NOR ANY OF SUCH UNITS MAY BE SOLD OR TRANSFERRED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION OF THEM UNDER THE ACT AND ANY OTHER APPLICABLE SECURITIES LAW, OR RECEIPT BY THE COMPANY OF AN OPINION OF COUNSEL OR OTHER EVIDENCE ACCEPTABLE TO THE COMPANY THAT SUCH SALE OR TRANSFER IS EXEMPT FROM REGISTRATION UNDER THE ACT. NEITHER THIS WARRANT NOR ANY OF SUCH UNITS MAY BE TRANSFERRED EXCEPT UPON THE CONDITIONS SPECIFIED IN THIS WARRANT, AND NO TRANSFER OF THIS WARRANT OR ANY OF SUCH UNITS SHALL BE VALID OR EFFECTIVE UNLESS AND UNTIL SUCH CONDITIONS SHALL HAVE BEEN COMPLIED WITH. TRANSFER OF THIS WARRANT OR ANY OF SUCH UNITS IS FURTHER RESTRICTED AS PROVIDED IN THE COMPANY’S AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT DATED (THE “ OPERATING AGREEMENT ”), A COPY OF WHICH IS AVAILABLE AT THE COMPANY’S OFFICES.

UNIT PURCHASE WARRANT

To Purchase Class A

Limited Liability Company Units of

BLACKHAWK BIOFUELS, LLC

THIS CERTIFIES THAT, for value received, the receipt and sufficiency of which is hereby acknowledged:

Subject to the conditions set forth herein, REG Ventures, LLC, with its principal offices at 416 S. Bell Avenue, Ames, Iowa 50010, together with any of its registered assigns or any transferee of all or any portion of its rights hereunder (the “ Holder ” or “ Holders ”), is entitled to subscribe for and purchase from Blackhawk Biofuels, LLC, a Delaware limited liability company (the “ Company ”), at any time or from time to time after the date hereof and continuing during the Exercise Period (as hereinafter defined), Fifty-one Thousand Five Hundred Sixty-three (51,563) fully paid and nonassessable Class A limited liability company units of the Company (the “ Units ”), at an exercise price of $.01 per Unit (the “ Exercise Price ”), subject to adjustment from time to time pursuant to the provisions of this Warrant (the “ Warrant Units ”). This Warrant is subject to the following provisions, terms and conditions:

Definitions . For the purpose of the Warrants, the following terms, whether or not capitalized or underlined in the text of this Warrant, shall have the following meanings:

“ Capital Units ” shall mean any and all shares, interests, participations, or other equivalents (however designated) of capital units of the Company.

“ Company ” shall have the meaning specified in the introduction to this Warrant, and shall include any corporation or business entity resulting from the merger, consolidation, or conversion of the Company.

“ Exercise Agreement ” shall have the meaning specified in paragraph 2(a) hereof.

“ Exercise Period ” shall have the meaning specified in paragraph 2(b) hereof.

“ Exercise Price ” shall have the meaning specified in the introduction to this Warrant.

“ Trading Days ” shall mean any days during the course of which the principal securities exchange on which the Common Stock is listed or admitted to trading is open for the exchange of securities.

“ Unit(s) ” shall have the meaning specified in the introduction to this Warrant.

“ Warrant(s) ” shall mean this Warrant of even date herewith, including all amendments to any such Warrants and all warrants issued in exchange, transfer or replacement therefor.

“ Warrant Units ” shall have the meaning specified in the introduction to this Warrant.

2. Exercise of Warrant .

(a) Exercise Agreement . While this Warrant remains outstanding and exercisable in accordance with subparagraph 2(a) below, the Holder may exercise, in whole or in part, the purchase rights evidenced hereby: (i) the surrender of the Warrant, together with a completed Exercise Agreement in the form attached hereto (“ Exercise Agreement ”) to the Secretary of the Company at its principal offices, (ii) the payment to the Company of an amount equal to the aggregate Exercise Price, for the number of Warrant Units being purchased, in cash (in the form of immediately available funds in U.S. Dollars); and (iii) full compliance with the other applicable provisions of this Warrant.

(b) Exercise Period . This Warrant is exercisable at any time from and after the date hereof (the “Exercise Period”) as follows: 20% of the Warrant Units through the one (1) year period from the date of this Warrant and an additional 20% of the Warrant Units on each one (1) year anniversary of this Warrant.

(c) Issuance of Certificates . Certificates for the Warrant Units, representing the aggregate number of Units specified in said Exercise Agreement, shall be delivered to the Holder within a reasonable time, not exceeding five (5) business days, after the rights represented by this Warrant shall have been so exercised. The Unit certificate or certificates so delivered shall be in such denominations as may be requested by the holder hereof and shall be registered in the name of said Holder or such other name as shall be designated by said Holder (subject to the transfer restrictions applicable to this Warrant and to Units purchased upon exercise of this Warrant). If this Warrant shall have been exercised only in part, then, unless this Warrant has expired, the Company shall, at its expense, at the time of delivery of said Unit certificates(s), deliver to said holder a new Warrant representing the right to purchase the number of Units with respect to which this Warrant shall not then have been exercised. The Company

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shall pay all expenses and charges payable in connection with the preparation, execution and delivery of Unit certificates (and any new Warrants) pursuant to this paragraph 2 except that, in case such Unit certificates shall be registered in a name or names other than the Holder of this Warrant or such Holder’s nominee, funds sufficient to pay all Unit transfer taxes which shall be payable in connection with the execution and delivery of such Unit certificates shall be paid by the Holder to the Company at the time of delivery of such Unit certificates by the Company as mentioned above.

(d) No Fractional Shares . This Warrant shall be exercisable only for a whole number of Warrant Units. No fractions of Units, or scrip for any such fractions of Units, shall be issued upon the exercise of this Warrant.

3. Units to be Fully Paid; Reservations of Units . The Company covenants and agrees that all Warrant Units will be duly authorized and validly issued and upon issuance in accordance with the terms and conditions hereof, will be fully paid and nonassessable and free from all taxes, liens and charges with respect to the issue thereof. Without limiting the generality of the foregoing, the Company covenants and agrees that it will from time to time take all such action as may be required to assure that the par value per Warrant Unit is at all times equal to or less than the Exercise Price then in effect. The Company further covenants and agrees that during the period within which the rights represented by this Warrant may be exercised, the Company shall at all times reserve and keep available out of its authorized but unissued Units, solely for the purpose of effecting the exercise of the rights represented by this Warrant and any other Warrants, such number of its Units as shall from time to time be sufficient to effect the exercise of all then outstanding Warrants; and if at any time the number of authorized but unissued Units shall not be sufficient to effect the exercise of all then outstanding Warrants, in addition to such other remedies as shall be available to the Holder, the Company will take such corporate action as may, in the opinion of its counsel, be necessary to increase its authorized but unissued Units to such number of Units as shall be sufficient for such purposes, including, without limitation, engaging in best efforts to obtain the requisite member approval of any necessary amendment to the Certificate or Articles of Organization

4. Anti-Dilution Provisions . The number, rights and privileges of the Units issuable upon exercise of this Warrant shall be subject to the following adjustments:

a. Subdivisions, Combinations and Stock Dividends . If the Company shall at any time prior to the expiration of this Warrant subdivide its Units, by split up or otherwise, or combine its Units, or issue additional Units as a dividend with respect to any Units, the number of Warrant Units issuable on the exercise of this Warrant shall forthwith be proportionately increased in the case of a subdivision or Units dividend, or proportionately decreased in the case of a combination. Appropriate adjustments shall also be made to the Exercise Price payable per share, but the aggregate Exercise Price payable for the total number of Warrant Units purchasable under this Warrant (as adjusted) shall remain the same. Any adjustment under this subparagraph 4(a) shall become effective at the close of business on the date the subdivision or combination becomes effective, or as of the record date of such dividend, or in the event that no record date is fixed, upon the making of such dividend.

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b. Other Distributions . In the event the Company shall declare a distribution payable in securities of other persons, evidences of indebtedness issued by the Company or other persons, assets (excluding cash dividends) or options or rights not referred to in subsection 4(b), then, in each such case for the purpose of this subsection 4(b), provision shall be made by the Company such that the Holder shall receive upon exercise of this Warrant a proportionate share of any such distribution s though it were the holder of the Units as of the record date fixed for the determination of the Unit holders of the Company entitled to receive such distribution.

c. Reclassification, Reorganization and Consolidation . If the Company shall effect any reclassification or similar change of the outstanding shares of the Company’s Capital Units (other than as set forth in subparagraph 4(a) or 4(b) above), or a consolidation or merger of the Company with another corporation, this Warrant shall, after such reorganization, reclassification, consolidation, or merger, be exercisable only for the number of Capital Units or other properties, including cash, to which a holder of the number of Units deliverable upon exercise of this Warrant would have been entitled upon such re