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                                                                   Exhibit 10.21




July 14, 1998


Stephen M. Schuster

--------------------------

--------------------------

Dear Steve:

     The following sets forth the terms and conditions of our "Agreement"
concerning your separation from employment and retainer:

1.   Due to the consolidation of the Envirodyne corporate office with the
management of Viskase Corporation ("Viskase") many of your responsibilities will
be eliminated or significantly reduced. Consequently, your employment with
Envirodyne Industries, Inc. ("Envirodyne") will be involuntarily terminated and
your last day of active employment will be Friday, July 31, 1998. Except as
specified herein your payroll and employee benefits from Envirodyne will cease
as of July 31, 1998.

2.   Effective August 1, 1998 you are engaged and retained by Envirodyne and
Viskase as an independent contractor to serve as needed and as available as Vice
President, Secretary and General Counsel of Envirodyne and Vice President of
Viskase and its subsidiaries from August 1, 1998 to July 31, 2000. In this
capacity you will report to me on such matters, duties and responsibilities as
assigned, oversee the legal function and represent Envirodyne in legal matters
before the Board of Directors. For your commitment and services you will be paid
an annual retainer of Fifty Thousand Dollars ($50,000) and a pro rata portion
thereof for any period less than a full year. Envirodyne and Viskase jointly and
severally agree to pay you this retainer monthly in twelve equal monthly
installments, payable on the first working day of each month. Viskase will also
reimburse you for all your reasonable out of pocket expenses in providing such
services including, without limitation, charges, disbursements, professional
licenses and association dues upon submission of a standard expense report form.
This retainer may be terminated by Envirodyne at any time after January 31, 2000
upon at least ninety (90) days prior written notice which notice may not be
given prior to January 31, 2000. You may terminate this retainer at any time
upon ninety days (90) prior written notice to Envirodyne. A Change of Control
(as defined in the Severance Policy) during the term of this retainer shall
result in the immediate termination of this retainer.

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3.   Pursuant to the Envirodyne Corporate Office Severance Policy ("Severance
Policy"), you would be eligible to receive on July 31, 1998 certain benefits due
to the elimination of the Envirodyne corporate office and your involuntary
separation from employment. Those severance benefits include, among other
things, twenty-four (24) months of salary and target bonus under the Envirodyne
Corporate Office Management Incentive Plan ("MIP"). The amount of such benefits
("Severance Benefit") are:

    Separation Pay ($14666.67/mo x 24 mos.)  = $  352,000
    Target Bonus ($176,000 x 40%)            = $   70,400
                                               ----------
    Total Severance Benefit                    $  422,400
                                               ==========

     In lieu of such Severance Benefit upon termination of employment, as part
of this Agreement, Envirodyne and Viskase jointly and severally agree to pay the
Severance Benefit of Four Hundred Twenty-Two Thousand Four Hundred Dollars
($422,400) to you in single lump sum, upon the first of the following to occur:
(a) July 31, 2000; (b) a Change of Control (as defined in the Severance Policy)
of Envirodyne or Viskase; (c) your death or permanent disability; (d)
termination of this Agreement by either party hereto; or (e) Envirodyne's or
Viskase's default in or failure to perform any of their respective obligations
under this Agreement.

4.   You will receive a pro rata bonus under the MIP for fiscal year 1998. This
payment will be made to you upon the completion of the independent audit but not
later than March 15, 1999.

5.   Currently, you have options for 66,250 shares of Envirodyne common stock,
38,117 of which are vested and 28,113 are unvested. While engaged under this
Agreement, your vested options will remain exercisable per the terms and
conditions of the Envirodyne Stock Option Plan; unvested options will not
expire, will remain in place and will vest according to your Option Agreements;
any unvested options would vest immediately in the event of the sale or Change
of Control of Envirodyne or Viskase. As so modified by this Agreement, the
Option Agreements with you shall remain in full force and effect.

6.   Your rights to indemnification and advancement of expenses as currently
provided in Envirodyne's By-Laws for the period you serve as an officer of
Envirodyne remain in effect. Envirodyne and Viskase shall each indemnify and
hold you harmless from and against any and all claims, liabilities, losses,
costs, damages or expenses (including attorney's fees) arising out of or in
connection with (i) Envirodyne's or Viskase's failure to perform any obligation
under this Agreement, (ii) any action taken by you at the request of Envirodyne
or Viskase, (iii) any other claim


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relating to your services hereunder which claim is not based upon any act or
omission adjudicated to constitute willful misconduct, fraud or dishonesty. In
addition, Envirodyne and Viskase each agree to advance your expenses as
currently provided for officers in Envirodyne's By-Laws. Notwithstanding
anything to the contrary contained herein, neither Envirodyne or Viskase shall
be required to indemnify you for any act or omission performed by you which
shall have been adjudicated to constitute willful misconduct, fraud or
dishonesty. Your activities under this Agreement will be covered under the
Envirodyne Directors and Officers liability insurance policy.

7.   This Agreement constitutes the entire agreement between the parties with
respect to the subject matter herein and shall be binding upon and inure to the
benefit of the parties and their respective successors, heirs and assigns.

     I have executed this Agreement as President and Chief Executive Officer of
Envirodyne and Viskase and am authorized to do so. If you are in agreement with
the foregoing, please sign the enclosed executed copy of this Agreement and
return it, whereupon this Agreement shall be legally binding on the parties
hereto.

                                        Very truly yours,


                                        ENVIRODYNE INDUSTRIES, INC.


                                        By:
                                           -------------------------------
                                           F. Edward Gustafson
                                           President and Chief
                                           Executive Officer


                                        VISKASE CORPORATION

                                        By:
                                           -------------------------------
                                           F. Edward Gustafson
                                           President and Chief
                                           Executive Officer


Accepted and agreed
this____day of July, 1998


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Stephen M. Schuster

FEG:gam