EXH 10.10

                 AGREEMENT FOR PLANT DESIGN STUDY AND MARKETING


         This  Agreement is made and entered  into as of July 22,  2000,  by and
between  RENTECH,  INC., a  corporation  organized  under the laws of the United
States  (Rentech),  and COMART,  a business  entity  organized under the laws of
Italy (Comart).

         The circumstances leading to this Agreement are as follows:

         A.   Rentech  has   developed  a   synthesis   gas-to-liquids   process
incorporating  Fischer-Tropsch  technology  with a  slurry  reaction  bed and an
iron-based catalyst known as the Rentech Gas-To-Liquids  Technology (Rentech GTL
Technology).  The Rentech GTL Technology is useful for converting carbon-bearing
gases into various liquid  hydrocarbons such as synthetic diesel fuel,  naphtha,
waxes, and other liquid hydrocarbon products.

         B.  Comart  wishes to obtain  certain  rights to market the Rentech GTL
Technology  for use with  natural gas  feedstocks.  Comart also wishes to engage
Rentech  to assist in the  preparation  of a basic  design  for a generic  1,000
barrel per day plant to use the Rentech GTL  Technology  to convert  natural gas
into liquid hydrocarbon products.

         Now,  therefore,  in consideration of the background  circumstances and
the following covenants, the parties agree as follows:

         1.  Marketing  Rights.  Rentech grants Comart  non-exclusive  rights to
market  Rentech's  licenses to use the Rentech  GTL  Technology  anywhere in the
world,  except  India,  for plants using  natural gas as  feedstock  that have a
production  capacity  of up to 2,000  barrels  per day of  liquid  hydrocarbons.
Rentech also grants Comart the exclusive  right to market  Rentech's  license to
use the Rentech GTL  Technology  anywhere in the world  except  India for plants
that may be  constructed  by ENI SpA and Edison SpA using  only  natural  gas as
feedstock.  Comart shall have no authority,  nor shall it represent  that it has
authority,  to bind or  commit  Rentech  to a  license  agreement  or any  other
obligation or commitment with any party. Rentech retains and reserves all rights
to determine the terms and provisions of its license agreements, catalyst supply
contracts  and  all  other  agreements  related  to the use of the  Rentech  GTL
Technology.

         2.   Cooperation.   If  Comart  obtains  one  or  more  customers  that
demonstrate  bona fide interest to Rentech in using the Rentech GTL  Technology,
Comer and Rentech will jointly consider the  opportunity.  If Rentech decides to
pursue the  opportunity,  Rentech  will conduct its own  negotiations,  with the
assistance of Comart, with the prospective  customer.  Rentech will negotiate in
good faith with each Comart  customer in an effort to reach  agreement  with the
customer as to the terms of a license  agreement and related  agreements for use
of the Rentech GTL  Technology  for each specific site proposed by the customer.
If Rentech and the customer agree upon mutually  acceptable terms,  Rentech will
provide a license  to the  customer,  or where  appropriate  a license to Comart
allowing Comart to grant a sub-license to the customer,  for each specific site.
To recognize the marketing costs  associated with this Agreement,  Rentech shall
pay to Comart, as its sole  compensation,  15% of any royalties Rentech actually
receives under a license  agreement from  production of liquid  hydrocarbons  in
plants originated by Comart.

         3. Technical Scope.



         3.1 Plant  Design  Study -  Technical  Support.  Rentech  will  conduct
engineering  services  for Comart to help to  prepare  the basic  designs  for a
generic  plant (one that is not intended  for any  specific  site or natural gas
feedstock)  including  process flow diagrams for a 1,000 barrel per day plant to
use the Rentech GTL  Technology to convert  natural gas into liquid  hydrocarbon
products such as synthetic  diesel fuel,  naphtha and waxes.  The design for the
generic plant will  emphasize  efficiency of capital costs and operating  costs,
which will  nevertheless  depend in part upon the location for any plant, with a
goal of obtaining the maximum ratio of performance to cost. If Comart  requests,
Rentech will also prepare  alternate  process flow  diagrams to enable Comart to
compare the capital and operating costs of the alternative configurations to use
various natural gas feedstocks.

         3.2 Plant  Design  Study - Fees.  For the  engineering  services  to be
carried out by Rentech in support of Comart,  as  described  in  paragraph  3.1,
Rentech will invoice  Comart  monthly for  materials and  engineering  services.
Rentech's  invoices  will  include  a  description  and the  actual  cost of the
materials  used and the  designation of level of experience of each engineer who
provided  services and the time spent by each on the plant design study.  Comart
agrees to pay for the cost of any  travel or other  out-of-pocket  costs and for
the cost of engineering services at the rates described in Appendix A.

         Comart agrees to pay Rentech's  invoices for materials and  engineering
services  within 30 days from the date of receipt of each  invoice  according to
Comart's regular month-end  payment schedule for its accounts payable.  Interest
shall accrue at the four percentage  points over the official Euro LIBOR rate in
effect at the time on sums not paid when due. Comart will pay Rentech's costs of
collection for unpaid sums, including attorneys?  fees and costs, and reasonable
travel  expenses.  All  payments  to  Rentech  will be in U.S.  dollars  by wire
transfer  to its  designated  bank  account.  Upon  default  by Comart in timely
payment  or in any other  obligation  under  this  Agreement,  Rentech  may,  in
addition to any other remedies available to it at law or in equity,  discontinue
all its  work  under  this  Agreement  and  hold as its  property  all  payments
previously  made by Comart as well as all work  product of Rentech  not  already
paid for by Comart.

         3.3 Fischer-Tropsch (FT) Synthesis Reactor Module. A Schedule A package
for  the FT  Synthesis  Reactor  Module  will be  prepared  by  Rentech  and its
subcontractors in accordance with the scope of work set forth in Appendix B. The
fixed cost for the Schedule A package,  including  deliverables  and the payment
terms, are set forth in Appendix B.

         3.4. Rentech will not start the work on the plant design study until it
receives  written  notice  to do so  from  Comart  that  includes  the  chemical
composition of the proposed  feedstock gas and the basis of the design  selected
by Comart, together with payment of the sum described in Appendix B.

         4. Waiver of License Fee.  Comart  understands  and agrees that Rentech
cannot license its technology in violation of any  restrictions  or prohibitions
imposed by the laws of the United  States.  No license  from Rentech is required
for it to conduct the plant design study for Comart. Accordingly, Rentech waives
its  customary  charge of a license fee for the  purposes  of this plant  design
study.  Rentech will require that a license  agreement  providing for payment of
license fees and  royalties and other  consideration  to Rentech be entered into
between it and anyone to whom the Rentech GTL  Technology  is  licensed.  In the
event of a change in  business  approach  to  accomplish  the  purposes  of this
Agreement,  Rentech and Comart will negotiate a new agreement to reflect the new
approach.



         5. Use of the  Plant  Design  Study.  Comart  will use the  information
provided  by the  plant  design  study to obtain  capital  cost  estimates  from
contractors  and suppliers of its choice for  construction of a 1,000 barrel per
day plant using the  Rentech GTL  Technology  for  conversion  of natural gas to
liquid hydrocarbons. Comart agrees to keep the capital cost estimates it obtains
confidential  and not to  disclose  them to  anyone  other  than  its  potential
customers.  The parties agree that the engineering drawings and other depictions
of the Fischer-Tropsch (FT) Synthesis Reactor Module that are proprietary,  such
as the internal  designs,  aspects,  configurations,  operating  conditions  and
functions of the reactor  module,  and catalyst  volume and  separation of waxes
from catalyst,  will remain in Rentech's possession and will not be removed from
the United  States  until a license  agreement  has been  executed  by  Rentech.
Rentech and Comart  will  cooperate  to enable  Comart and its  contractors  and
suppliers  to  examine  and  study  these  engineering   drawings  at  Rentech's
facilities in Denver, Colorado, provided that no copies or other duplications of
them may be made.

         6.  Export  Licenses.  Any and all  obligations  of Rentech  under this
Agreement to provide Comart with any technical services or information,  for any
purpose  or  pursuant  to  any  other  contract   between  them,  are  expressly
conditioned   upon  Rentech   obtaining   any  and  all  export  and   re-expert
authorizations  and  licenses  that may from time to time be  required of it for
such purposes under United States law. Rentech agrees to use its best efforts to
obtain  authorizations  and licenses required of it, but its inability to obtain
such  authorizations  and  licenses  shall  not  constitute  a  breach  of  this
Agreement.  If  Rentech is unable to obtain  such  authorizations  or  licenses,
Comart may, but is not required to, attempt to do so at its expense.

         7.  Reservation of Rights by Rentech.  Rentech  reserves the right,  by
itself or with  others,  to  develop,  design,  construct,  license and sell all
synthesis  gas  reactors  for use of the Rentech GTL  Technology  and to prepare
their  designs and  specifications,  including  without  limitation,  processes,
plans,  flow  sheets,  drawings  related  to  the  internal  designs,   aspects,
configurations,  operating  conditions  and functions of the reactors,  catalyst
volume and catalyst  recovery.  Rentech also  reserves  ownership of any and all
rights to all proprietary  information and other know-how,  technology and trade
secrets contained in the process flow diagrams,  heat and mass balance diagrams,
process plans, engineering designs and specifications, instrumentation drawings,
computer  software  programs  and  source  and object  codes,  construction  and
fabrication  standards and  specifications,  operating  standards and procedures
provided by Rentech in the  drawings for the plant design study or in the course
of  presenting  the plant design  study.  Comart will own the plant design study
drawings.

         8. Term. The term of this Agreement shall extent for two (2) years from
the date stated in the introductory  paragraph.  The term shall be automatically
renewed for additional  successive  periods of one (1) year each,  unless either
party gives the other written notice  ninety(90) days before the end of the term
then in effect that it does not wish to extend the term.  The  obligation to pay
any fees or other sums of money for obligations  entered into before  expiration
of hits Agreement will survive termination of this Agreement.

         9. Confidentiality.

         9.1 Information  That Is Confidential;  Obligation of  Confidentiality.
Comart agrees that the terms of this  Agreement are to be strictly  confidential
except to the  extent  required  to be  disclosed  by law.  In  addition  to the
provisions of any separate,  additional  agreements of  confidentiality  between



them,  Comart agrees that all information that it receives from Rentech relating
to the Rentech GTL  Technology;  (i) the results of the plant design study,  all
aspects of the design and operating  process of synthesis  gas reactor  modules;
(ii)  formulas  for the use and  induction  of  Rentech's  catalyst;  (iii)  the
designs,  plans and  prospects  of Rentech for  development  of plants using the
Rentech  GTL  Technology,  and  (iv)  all  other  know-how,  trade  secrets  and
proprietary  information  of Rentech  including  processes,  formulas,  software
programs  and source  and object  code,  improvements,  inventions,  techniques,
induction  procedures,  designs and plans for  Rentech  plants,  forecasts,  new
products,  customer lists,  information regarding prospective financing sources,
feedstocks,  competitors,  fee and royalty amounts  charged by Rentech,  and (v)
non-published   financial   information   relating   to  Rentech   (Confidential
Information) shall be considered  confidential,  except as specified in the next
section  of  this  Agreement.   In  addition,   all  information   described  as
confidential in other written confidentiality agreements executed by the parties
shall be  considered  confidential,  except as  specified in the next section of
this Agreement. Comart agrees that it shall neither use such information, except
pursuant to and in accordance  with the terms and conditions of this  Agreement,
nor disclose such  information to anyone except to its employees and agents that
Comart  determines need to know in connection with the  development,  financing,
construction  or operation  of any plant  licensed by Rentech to use the Rentech
GTL  technology and whose  knowledge of such  information is necessary to effect
the  purposes  of  this  Agreement.   Comart  may  only  disclose   Confidential
Information  to such  person if (i) such person has  executed a  confidentiality
agreement  maintained by Comart in substantially the form of these provisions on
confidentiality,  or (ii) Comart has taken other reasonable steps to ensure that
such person will maintain the  confidentiality  of the Confidential  Information
during  the  term  of  this  Agreement,  and for  the  additional  period  after
termination or expiration of this Agreement  until such time as the  information
ceases being  Confidential  Information  pursuant to the  provisions of the next
section.   Comart  shall  maintain  the   confidentiality  of  the  Confidential
Information  during the  continuance of this Agreement and thereafter  until the
information  ceases being  confidential  pursuant to the  provisions of the next
section.

         9.2 Exception to Confidentiality.  It is agreed, as an exception to the
foregoing  obligations of confidentiality,  that information  received by Comart
from Rentech as a result of this Agreement shall not be considered confidential,
and Comart  shall not be limited in  disclosing  the same,  if and to the extent
that the information, as shown by competent evidence, (i) is or becomes, through
no fault of the party  obligated  to  maintain  confidentiality,  in the  public
domain;  (ii) is lawfully obtained by Comart from a source other than Rentech or
its agents;  (iii) was already  known by Comart at the time of its  receipt,  as
shown by reasonable  proof filed with Rentech within a reasonable time after its
receipt;  or (iv)  required  to be  disclosed  by law or order  of any  court or
governmental  authority  having  jurisdiction.  Disclosures  that are  specific,
including   but  not  limited  to  operating   conditions   such  as  pressures,
temperatures,  formulas,  procedures  and other like  standards and  conditions,
shall not be deemed to be within the foregoing  exceptions  merely  because they
are  embraced  by general  disclosures  available  to the  general  public or in
Comart's  possession.  Additionally,  any  combination  of features shall not be
deemed to be within the  foregoing  exceptions  merely  because  the  individual
features are available to the general  public or in Comart's  possession  unless
the  combination  itself and its  principle  of operation  are  available to the
general public.

         9.3 Published  Disclosure.  It is agreed that the disclosure of certain
information  by  Rentech  in a  publication,  such as in  letters  patent  or by



otherwise  placing  it in the  public  domain,  will  not free  Comart  from its
obligation to maintain in confidence any information not specifically  disclosed
in or fairly  ascertainable  from the publication or other disclosure,  such as,
for example,  the fact that  information in the publication or any portion of it
is or is not used by  either  party.  Comart  shall  have the  right to  publish
information or articles pertaining to the Rentech GTL Technology, and its liquid
hydrocarbon  products only if such  information is not  confidential,  and, with
respect  to  Confidential  Information,  only upon  prior  written  approval  by
Rentech, which Rentech may withhold in its absolute discretion.

         9.4 Non-Use after  Termination.  Comart shall not use the  Confidential
Information  after  termination or expiration of this Agreement unless and until
such time as the information ceases being Confidential  Information  pursuant to
the provisions of this section.

         10.  Consequential  Damages. In no event shall either Comart or Rentech
be  liable  to the  other,  whether  arising  under  contract,  tort  (including
negligence),  or  otherwise,  for loss of  anticipated  profits or  revenue,  or
opportunities  if the  design  prepared  for  Comart  is not  used in any  plant
constructed to use the Rentech GTL  Technology.  Comart assumes the risk that it
may not be able to find  customers  who can obtain a license from  Rentech,  for
legal reasons or otherwise. Comart will in any event pay the sums due to Rentech
for the plant design  study.  Rentech makes no  warranties,  express or implied,
with respect to use of the Rentech GTL Technology.

         11.  Applicable  Law. This agreement shall be governed by and construed
in accordance with the laws of the state of Colorado,  United States of America,
(without regard to conflicts of law). All suits,  actions or proceedings arising
out of or related to this agreement (related  proceedings) shall be brought in a
court of competent  jurisdiction  located in Denver  County,  Colorado,  each of
which courts  shall be an  appropriate  forum for all such related  proceedings.
Each party hereby waives any objection  which it ay now or hereafter have to the
jurisdiction of any such court over, or the laying of venue in any such court or
any such related proceeding.

         12.  Compliance.  Comart and Rentech agree to strictly  comply with all
applicable  laws,  regulations  and  orders of the  United  States.  Each  party
acknowledges  and agrees that certain laws of the United  States,  including the
foreign Corrupt  Practices Act, (15 U.S.C.  Sections 78dd-1 et seq.),  prohibits
any person  subject to the  jurisdiction  of the United  States  from making any
payment of money or anything of value,  directly or  indirectly,  to any foreign
government official, foreign political party, or candidate for foreign political
office  for  the  purpose  of  obtaining  or  retraining  business.  Each  party
represents and warrants that, in the performance of its  obligations  under this
Agreement, it has not made, and will not make, any such proscribed payment. Each
party shall  indemnify  and hold the other party and its  affiliates,  officers,
directors,  agents and employees harmless against any and all claims, losses and
liabilities attributable to any breach of this provision.

         13. Invalidity of Provision. If any of the provisions of this Agreement
shall be held by a court or administrative  agency of competent  jurisdiction to
contravene  the laws of any  country,  it is  agreed  that  such  invalidity  or
illegality  should not invalidate the whole Agreement,  but this Agreement shall
be construed as if it did not contain the  provision  or  provisions  held to be
invalid or illegal in the particular jurisdiction concerned, and insofar as such
construction  does not affect the substance of this Agreement and the rights and
obligations  of  the  parties  hereto,   it  shall  be  construed  and  enforced
accordingly.  In the event,  however,  that such invalidity or illegality  shall
substantially  alter the  relationship  between  the parties  hereto,  affecting
adversely the interest of either party,  then the parties hereto shall negotiate
a mutually acceptable alternative provision not conflicting with such laws.



         14.   Notices.   Any  notice,   payment,   request,   demand  or  other
communication  hereunder  shall be in  writing  and shall be deemed to have been
duly given when (i) delivered personally, upon personal delivery to the party to
be notified; or (ii) one business day after sent by facsimile  transmission with
confirmation  by the  sending  party's  facsimile  machine  that the message was
received by the party to be notified, or (iii) seven business days after sent by
airmail,  registered  or  certified  mail,  postage  paid,  to the  party  to be
notified, at the address set forth below:

  Rentech, Inc.:                COMART:
  Dennis L. Yakobson, President      Massimillano Guglielminetti, Vice
                                     President
  Rentech, Inc.                 Comart
  1331 17th St., Suite 720      Via Raffaello Sanzio 2d
  Denver, Colorado 80202             21013 Gallarate (VA) - Italy

Either party may change its address,  facsimile number or  representative  to be
notified by written notice to the other party.

         15.  Assignment.  Neither  party  shall  transfer  or assign any of its
rights,  liabilities,  or obligations  under this Agreement  without the express
written  consent  of the other  party,  other than to one of its  subsidiary  or
affiliated companies;  provided,  however, that the assigning party shall not be
relieved of any of its  obligations  under this  Agreement.  This  Agreement  is
binding upon the successors and permitted assigns of the parties.

         16.  Expenses.  Except as may be  otherwise  agreed to in writing  each
party shall be responsible  for and bear its own costs and expenses  incurred in
connection with the performance of its obligations under this Agreement.

         17.  Miscellaneous.   This  Agreement  contains  every  obligation  and
understanding  between the Parties  relating  to the subject  matter  hereof and
merges all prior discussions, negotiations and agreements, if any, between them,
except for the Pre-Bid Agreement between them dated May 24, 2000. Neither of the
parties  shall  be  bound  by  any  conditions,   definitions,   understandings,
warranties or  representations  relating to the subject matter hereof other than
as expressly  provided for or referred to in this Agreement.  This Agreement can
be amended only by written  instrument  properly  executed by the  parties;  any
purported  amendment not in writing and properly executed shall be null and void
and of no effect.

         18.   Counterparts.   This   Agreement   may  be  executed  in  several
counterparts,  and all copies so executed shall  constitute but one and the same
agreement, which shall be binding on all the parties hereto notwithstanding that
less  than  all  of the  parties  may  have  signed  the  original  or the  same
counterpart.



         IN WITNESS WHEREOF,  the Parties have executed this Agreement as of the
date herein above first stated.

RENTECH, INC.                 COMART

By:  /s/ Dennis L. Yakobson            By: /s/ Massimillano Guglielminetti
- ---------------------------            -----------------------------------
Name:  Dennis L. Yakobson              Name:  Massimillano Guglielminetti
Its: President                         Its: Vice President





APPENDIX A

Charges for Engineering Services


Designation of Engineer or Technician        Hourly Rate

Senior Scientist                             $293/hour
Senior Engineer                              $250/hour
Engineer                                     $152/hour

Rentech estimates that the cost of these engineering services will not exceed US
$50,000.



APPENDIX B

SCHEDULE A

         The following  outline  describes the  information to be provided.  The
fixed cost of Rentech, Inc. for the following Schedule A package is US $250,000.
One-half  of the  payment  (US  $125,000)  is due at the  start of this task and
one-half  (US  $125,000)  upon  submittal of the Schedule A package to Comart or
other payment terms as may be negotiated between the parties.