
                                                                Exhibit 10n

The omitted portions  indicated by brackets have been separately filed with
the  Securities  and  Exchange   Commission   pursuant  to  a  request  for
confidential treatment under Rule 406, promulgated under the Securities Act
of 1933, as amended.

                        JOINT DEVELOPMENT AGREEMENT
                        ---------------------------


     This Agreement is effective as of the 11th day of November 1996 by and
among Engelhard Corporation ("Engelhard") having a place of business at 101
Wood Avenue,  Iselin,  New Jersey 08830;  Clean Diesel  Technologies,  Inc.
("CDT")  having a place of  business  at 300  Atlantic  Street,  Suite 702,
Stamford,  Connecticut 06901; and Nalco Fuel Tech ("NFT") having a place of
business at 1001 Frontenac Road, Naperville, Illinois 60563.

     Engelhard has developed NOx reduction  catalysts and systems which can
reduce  NOx  emissions  in the  exhaust  stream  of diesel  engines  in the
presence of an amine-based  reagent through selective  catalytic  reduction
(SCR).

     CDT and NFT have  independently  developed and own  reagents,  reagent
injection  techniques,  injector designs,  metering  systems,  and computer
models that, in conjunction with an NOx reduction catalyst,  will reduce NOx
emissions from diesel engines.

     CDT,  NFT  and  Engelhard  wish  to  collaborate  on the  development,
demonstration,  and commercialization of a urea-based SCR System for use on
diesel engine power  generator sets  manufactured by Cummins Engine Company
("Cummins").

     Therefore, the parties agree as follows:

     1.  Engelhard,  CDT, and NFT will  collaborate  on the  selection  and
     testing of Engelhard  catalysts and reactors in  conjunction  with the
     CDT and NFT supplied reagent,  injectors, and metering equipment prior
     to the  prototype  testing of the System.  Pre-prototype  testing will
     take place at the Engelhard  engine lab during 1996 to define  overall
     system performance.

     2.  CDT and NFT will  share  confidential  Cummins  engine  data  with
     Engelhard for catalyst  selection and design,  based on  authorization
     from Cummins.  This sharing is contingent upon Engelhard  holding such
     information in strict confidence,  in accordance with the requirements
     of CDT's and NFT's Confidentiality Agreement with Cummins.

     3. Prototype testing of the System will take place in conjunction with
     Cummins on an engine  supplied by Cummins during 1997.  Engelhard will
     provide  catalysts  and  reactors  and CDT and NFT  will  provide  the
     reagent and  injection/metering  system. The timing and responsibility
     for testing shall be agreed by the parties in advance.

     4. Upon successful  completion of prototype  testing of the System and
     based on  agreement  by the  parties  with  Cummins  to  proceed  with
     commercialization  of the System, the parties shall support commercial
     performance and durability testing of the System as mutually agreed by
     the parties with Cummins.  Engelhard will provide catalyst and reactor
     and  CDT  and NFT  will  provide  the  injection/metering  system  and
     reagent.

          Unless  otherwise  agreed by the parties in  writing,  the direct
     cost of the engine,  engine operations,  emissions  monitor,  and data
     collection  during the  durability  testing  shall not exceed $[ ] per
     party, with each party paying one-third of the total.

     5.  Upon   successful   completion  of   durability   testing  to  the
     satisfaction  of the parties and Cummins,  the parties shall negotiate
     with Cummins for supply of  commercial  Systems.  CDT and NFT shall be
     the overall System supplier, with catalyst and reactor supplied to CDT
     and NFT by Engelhard based on mutually agreed price and terms.

     6. Parties confirm that they agree not to analyze or have analyzed any
     chemical   reagents,   injectors,   metering  equipment  or  catalysts
     (hereinafter   "Samples")   provided  by  one  party  to  another  for
     evaluation  during this  Agreement,  and that all such Samples will be
     provided  free of charge and shall be returned to the party  providing
     such Samples at the end of each test.

     7. (a) Each party shall have equal  access to the test results for all
     tests conducted in accordance  with this  Agreement.  Data and results
     resulting from the work completed during this program ("Subject Data")
     shall be jointly  owned by the  parties,  but no party  shall have the
     right to publish  or  disclose  such data  without  the prior  written
     consent of the other parties,  which consent will not be  unreasonably
     withheld.  Any  inventions  first  jointly  conceived  and  reduced to
     practice  from  the  work  completed  under  this  program   ("Subject
     Inventions") shall be owned by the parties. Any patents resulting from
     Subject  Inventions  will  be  owned  by NFT if  related  to  metering
     equipment or reagents,  and by Engelhard if related to catalyst.  Each
     of the two other  parties to this  agreement  shall  have a  worldwide
     royalty-free  license to make,  use, and sell subject to payment of a
     one-third  share  of  reasonable   patent   preparation,   filing  and
     maintenance costs. Any inventions  individually  conceived during this
     program or conceived  and reduced to practice  outside of this program
     will in no event be Subject Inventions. 

     (b) All inventions,  patents, patent applications,  data, know-how and
     other  intellectual  property in the  possession of or owned by any of
     the parties  prior to the Test shall remain the property of such party
     and no grant of any right or license  whatsoever  thereunder to any of
     the  other   parties  is   intended   hereby  or  should  be  implied,
     notwithstanding  that rights in any such intellectual  property may be
     necessary to enable a party to practice a Subject Invention. No rights
     or  obligations  other than those  expressly  recited herein are to be
     implied from this Agreement. Except as provided above, and relating to
     Subject  Inventions  and Subject Data,  no license is hereby  granted,
     directly or indirectly,  under any know-how or patent now or hereafter
     held by or licensed by any of the parties.

     9. This  Agreement  shall be governed by and  construed in  accordance
     with the internal  laws of the State of New Jersey  without  regard to
     the principle of conflict of laws.

     10. This Agreement  constitutes the entire  understanding  between the
     parties hereto with respect to the subject matter indicated above, and
     its terms may not be  changed or amended  except by an  instrument  in
     writing.


     IN WITNESS  WHEREOF,  the parties  have caused  this  Agreement  to be
signed in triplicate by their duly authorized representatives.


CLEAN DIESEL TECHNOLOGIES, INC.           ENGELHARD CORPORATION

By:                                       By:
   ------------------------------            ------------------------------

Name:  James M. Valentine                 Name:
     ----------------------------              ----------------------------

Title: Chief Operating Officer            Title:
      ---------------------------               ---------------------------

Date:                                     Date:
     ----------------------------              ----------------------------


NALCO FUEL TECH

By:
   ------------------------------

Name:
     ----------------------------
Title:
      ---------------------------
Date:
     ----------------------------
