EXECUTION COPY


     This TECHNOLOGY  PURCHASE AGREEMENT (the "Agreement"),  made as of the 30th
day of June, 1997,  between  ADVANCED  PARTICLE  TECHNOLOGIES,  INC., a Delaware
corporation  ("APT"),  and  VANGKOE  INDUSTRIES,  INC.,  a  Florida  corporation
("VANGKOE");

                                   WITNESSETH:

     WHEREAS, VANGKOE is the owner of the proprietary particulate  color-coating
technology described on Exhibit A hereto (the "Technology"); and 

     WHEREAS,  APT desires to purchase,  and VANGKOE desires to sell to APT, the
Technology in accordance with the terms hereof; and

     WHEREAS, simultaneously with the execution and delivery hereof, the parties
are entering into a Distributor Agreement (the "Distributor Agreement") pursuant
to which,  among other  things,  VANGKOE will become a  distributor  of products
manufactured and color-coated by APT utilizing the Technology;


     NOW THEREFORE, in consideration of the premises and of the consideration to
be  received  by  the  parties  hereunder,  and  for  other  good  and  valuable
consideration,  the receipt and sufficiency of which is hereby acknowledged, the
parties hereby agree as follows:

     1.  Purchase and Sale of  Technology.  VANGKOE  hereby sells and assigns to
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APT, and APT hereby purchases from VANGKOE,  all of VANGKOE's  right,  title and
interest  in and to the  Technology.  The  parties  agree that for the  purposes
hereof, the term Technology shall include all formulae, inventions, know-how and
other proprietary rights constituting and embodied in the Technology,  such that
this  transfer  will  vest APT  with  complete  and  absolute  ownership  of the
Technology  and the sole  right to modify,  enhance,  improve  and  commercially
exploit the same.

     2.  Purchase  Price.  (a) The purchase  price for the  Technology  shall be
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$100,000  (with the right to receive the  additional  payments set forth below),
payable by check or wire  transfer to an account  designated  by  VANGKOE.  Such
purchase price is payable as follows:

     (i) $75,000 has been paid prior to the date hereof pursuant to the terms of
the Letter of Intent dated February 14, 1997,  between  VANGKOE and APT relating
to, among other things, the transaction contemplated hereby; and

     (ii) $60,000 will be paid simultaneously with the execution and delivery of
this Agreement.
<PAGE>

     (b) In addition,  VANGKOE will have the right to receive,  by check or wire
transfer  to an account  designated  by  VANGKOE,  an  additional  $30,000  upon
satisfactory production of all colors set forth in Section 2(d) and satisfactory
documentation  of the  related  formulas.  Such  determination  shall be made in
accordance with Section 2(c).

     (c) The parties  acknowledge that achievement of the requirements set forth
in Section  2(b) will require the  diligent  good faith  efforts of both parties
(and, with respect to VANGKOE,  the diligent good faith efforts of Bo Gimvang in
particular),  and each  party  hereby  commits to use such  diligent  good faith
efforts to cooperate to achieve the satisfaction of such requirements  within 60
days  following  the  date  hereof  or  as  soon  thereafter  as  possible.  The
determination of satisfaction of such  requirements  shall be made by APT acting
in good faith and on a  reasonable  basis.  In the event of a dispute  regarding
such  determination,  such  dispute  shall be subject to the dispute  resolution
procedure established pursuant to Section 6.2 hereof.

     (d) The parties expressly acknowledge that the payments to be made pursuant
to this  Section 2, and the good faith  efforts to achieve  the  milestones  set
forth in this Section 2, are in respect of the following colors deemed necessary
by the  parties  to  effectively  compete  in the  Market:  black,  blue,  teal,
turquoise,  jade, light blue, dark blue and the blue color required by VANGKOE's
prospective  customer  Rhino-coat.  Accordingly,  APT  acknowledges  that to the
extent that it desires  Vangkoe to provide  assistance  to develop other colors,
APT will pay for the consulting services of Vangkoe at the rate of $150 per hour
(or such other amount as shall be agreed upon by the parties). Vangkoe agrees to
use its good faith  efforts  to  provide  the  services  of Bo Gimvang  and Jeff
Koebrick in that regard to the extent possible without unreasonably  interfering
with the  abilities of such persons to perform the services  required of them to
Vangkoe.

     (e) It is expressly understood and agreed by the parties that the amount of
technology  transfer  payments  made pursuant to this section 2 include all past
research and development, out of pocket expenses and associated costs, reflected
in the lump sum payments by APT to VANGKOE hereunder.

     3.  Royalty  Payment.  If APT or its  affiliates  shall sell  color  coated
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particles  utilizing  the coating  technology  purchased by APT pursuant to this
Technology Purchase Agreement, as the same may be modified, enhanced or improved
by APT, to any  customer for use in any market other than the market (as defined
in the Distribution Agreement),  or to any customer (other than VANGKOE) for use
in the Market (in the event VANGKOE  fails to maintain its  exclusive  rights to
distribute  the  Products in the  Market),  APT or its  affiliates  shall pay to
VANGKOE a royalty  equal to $0.02 per pound of coated  material  sold during the
term of this  Agreement  and $0.01 per pound of coated  material sold during the
five-year period following the termination of this Agreement.  Such payment will
be made on a semi-annual  basis on or prior to March 31 and September 30 of each
year and shall be accompanied by reasonably  detailed  documentation  supporting
the calculation of such royalty. Such royalty shall be due regardless of whether
the coating  technology  was applied at APT's  current  St.  Augustine,  Florida
facility or at another new or existing facility of APT or any of its affiliates,
suppliers or customers.  If VANGKOE shall  disagree with the  calculation of any
semi-annual royalty


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<PAGE>

payment,  VANGKOE shall  provide  written  notice  thereof to APT within 10 days
following its receipt of the calculation and payment. VANGKOE and APT shall then
work together in good faith to resolve the dispute  within the following  30-day
period. During such period, VANGKOE shall have the right to review the books and
records of APT and its  affiliates  with respect to coated product sales and the
calculation  of the royalty  payment at the  offices of APT (or its  affiliates)
during normal  business hours and at VANGKOE's sole expense.  If the parties are
unable to resolve the dispute  within such 30-day  period,  the dispute  will be
resolved by arbitration in accordance with Section 6.2 below.

     4. Certain Additional Agreements.
        ------------------------------

     (a) VANGKOE  recognizes the highly competitive nature of the business to be
conducted by APT and the  importance of preserving  the  confidentiality  of the
Technology.  Accordingly,  as an inducement to APT to enter into this  Agreement
and in partial consideration of the amounts to be received by VANGKOE hereunder,
as  well as the  benefits  to be  realized  by  VANGKOE  under  the  Distributor
Agreement, VANGKOE agrees that (i) it will not, directly or indirectly, disclose
(verbally,  in writing or otherwise) the  particulate  color-coating  formula or
process that  constitutes  the  Technology to any third party and (ii) until the
later of the fifth  anniversary  of the date hereof and the  termination  of the
Distributor  Agreement,  it will  not,  directly  or  indirectly,  engage in the
business,  or assist any other party (except APT or its  affiliates) in engaging
in the  business,  of  manufacturing  color-coated  particles or  developing  or
selling color-coating  technologies for particles;  provided,  however, that (A)
                                                    --------   -------
the  restrictions  set forth in clause (i) above shall not apply after such time
as the formula and process  constituting the Technology enters the public domain
through the issuance of a patent or  otherwise  becomes  generally  known to the
public (as evidenced by academic or trade books, articles or journals or similar
written publicly  available  sources and (B) the restriction set forth in clause
(ii) above shall cease to apply 20 days following  notice by VANGKOE to APT of a
material  breach by APT or its affiliates of any material term of this Agreement
or the  Distributor  Agreement  (unless  such breach is cured within such 20-day
period).

     (b) VANGKOE  acknowledges and agrees that simultaneously with the execution
and delivery of this Agreement,  each of Cytech  Laboratories,  Inc. ("Cytech"),
Jeff  Koebrick  and Bo Gimvang  will sign a letter  pursuant  to which they will
agree to be bound by this Section 4.

     (c) APT and its  affiliates  acknowledge  that  Cytech  is a  research  and
development  company  controlled by Jeff Koebrick and Bo Gimvang and that Cytech
develops alkali silicate coatings for various commercial  applications.  APT and
its affiliates hereby  acknowledge that the purchase hereunder is limited to the
Technology  and that neither APT nor its affiliates has purchased or will assert
rights with respect to other alkali  silicate  coating  formulas or processes of
Cytech.(d) The parties  acknowledge that they hope to be engaged in a long-term,
mutually beneficial relationship.  Accordingly,  APT and its affiliates agree to
evaluate in good faith any potential coating technology or other technology that
could be  applicable  and  beneficial to the business to be conducted by APT and
VANGKOE  agrees to use 


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<PAGE>

its good faith efforts to provide APT and its affiliates  the first  opportunity
to review and evaluate any such  technologies  for  commercial  exploitation  on
terms to be agreed upon by the parties.

     5.  Representations and Warranties.  (a) Each party represents and warrants
         -------------------------------
to the other that such party is duly incorporated,  validly existing and in good
standing  under the laws of the State of its  incorporation.  Each party further
represents  and  warrants  to  the  other  that  the  execution,   delivery  and
performance of this Agreement and the  Distributor  Agreement have been duly and
validly  authorized  by all  necessary  corporate  action.  Each  party  further
represents  and warrants to the other that neither the  execution,  delivery nor
performance  of  this  Agreement  or the  Distributor  Agreement  will  violate,
conflict  with or cause a default  under (with or without due notice or lapse of
time)  its  Certificate  of  Incorporation  or  By-laws  or any  contract,  debt
obligation or other agreement or instrument by which it is bound.

     (b) VANGKOE  represents  and warrants to APT (and  Conversion  Technologies
International,  Inc.  ("CTI"),  which shall be a third party beneficiary of this
representation  and warranty) that (i) it has good and valid title to the shares
(the "Shares") of APT Common Stock being transferred to CTI simultaneously  with
the execution and delivery of this Agreement, (ii) the transfer of the Shares to
CTI in consideration of $0.01 per share has been duly and validly  authorized by
all necessary  corporate  action by VANGKOE and (iii) the delivery to CTI of the
certificate  representing the Shares,  together with a duly executed stock power
assigning the Shares to APT,  will be  sufficient  to transfer  ownership of the
Shares to CTI, free and clear of any claims, liens, pledges,  security interests
or other encumbrances of any nature whatsoever.

     (c) VANGKOE's  representations and warranties set forth in the letter dated
May 9, 1996, a copy of which is attached  hereto as Exhibit B, are  incorporated
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herein by reference  as if set forth  herein in their  entirety and made for the
benefit of APT as well as CTI.

     Section 6. Miscellaneous.
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     6.1 Notices.  Any notice required or permitted  hereunder shall be given in
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writing and shall be  conclusively  deemed  effective  when given upon  personal
delivery or delivery by courier, or five days after deposit in the United States
mail, by registered or certified mail, postage prepaid, addressed as follows (or
at such other address as may be designated by written notice):

     (i)          if to APT, to:

                  Advanced Particle Technologies, Inc.
                  c/o Conversion Technologies International, Inc.
                  82 Bethany Road
                  Hazlet, New Jersey  07730
                  Telephone:  (908) 888-3828
                  Telecopier: (908) 888-3930
                  Attention:   President

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<PAGE>

                              and

     (ii)         if to VANGKOE, to
                  VANGKOE Industries, Inc.
                  7 San Bartola Drive
                  St. Augustine, FL  32086
                  Telephone:  (904) 824-0111
                  Telecopier:  (904) 824-7994
                  Attention:    President

     6.2 Dispute  Resolution.  In the event of any  dispute  between the parties
         --------------------
under this  agreement,  the parties shall attempt to resolve it in good faith as
soon as  possible.  If such  dispute is not  resolved  within 20 days  following
written  notice  thereof  from one party to the other (or such number of days as
shall  be  otherwise  specified  herein),  such  dispute  shall be  resolved  by
arbitration  pursuant to the rules of the American  Arbitration  Association  or
other  mediation  procedure  agreed  to by  the  parties.  Such  arbitration  or
mediation shall take place in St. Augustine, Florida or other mutually agreeable
location.  The  arbitrator  or mediator will be instructed to attempt to resolve
the dispute within 30 days of commencement of proceedings and any award shall be
final and binding upon the parties,  unless non-binding arbitration or mediation
is  mutually  agreed  upon.  Each  party  will bear its own legal fees and other
expenses related to any such proceeding.

     6.3  Assignment.  This Agreement may not be assigned by VANGKOE without the
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prior  written  consent of APT or,  whether by  operation  of law or  otherwise,
except to a purchaser of substantially  all of the assets or business of VANGKOE
following  APT's (or its  affiliates')  refusal to  exercise  its right of first
offer under the Distributor Agreement. This Agreement may not be assigned by APT
and/or its affiliates  without the prior written consent of VANGKOE,  whether by
operation of law or  otherwise,  except to an affiliate of APT or to a purchaser
of  substantially  all of the  assets or  business  of APT  following  VANGKOE's
refusal to exercise its right of first offer under the Distributor Agreement.

     6.4 Independent  Contractors.  The parties are independent  contractors and
         -------------------------
neither party has, or will  represent  that it has,  authority to bind the other
with respect to any matter whatsoever.

     6.5  Amendments.  This  Agreement  may not be amended  without  the written
          -----------
agreement of the parties.

     6.6 Entire Agreement.  This Agreement constitutes the complete agreement of
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the parties with respect to the subject  matter hereof and  supersedes all prior
agreements of the parties, if any, whether oral or in writing,  and no course of
dealing shall alter the terms hereof.

     6.7  Severability.  In the event that any provision of this Agreement would
          -------------
be  held  in  any  jurisdiction  to be  invalid,  such  jurisdiction,  shall  be
ineffective,  without invalidating the remaining provisions of this Agreement or
affecting  the  validity  or  enforceability  of  such  


                                      -5-
<PAGE>

provision in any other  jurisdiction.  Notwithstanding  the  foregoing,  if such
provision  could be more narrowly  drawn so as not to be invalid,  prohibited or
unenforceable in such  jurisdiction,  it shall, as to such  jurisdiction,  be so
narrowly drawn,  without invalidating the remaining provisions of this Agreement
or  affecting  the  validity or  enforceability  of such  provision in any other
jurisdiction.

     6.8 Successors and Assigns.  Subject to the  limitations  set forth herein,
         -----------------------
this Agreement shall be binding on each party's successors and assigns.

     6.9  Governing  Law. This  Agreement  shall be governed by and construed in
          ---------------
accordance  with the laws of the State of  Delaware,  without  giving  effect to
principles of conflicts of laws.

     6.10 Counterparts.  This Agreement can be signed in counterpart,  with each
          -------------
such counterpart constituting an original but all such counterparts constituting
one agreement.



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<PAGE>


      IN WITNESS WHEREOF, the undersigned have entered into this Agreement as of
the date appearing on the first page hereof.


                                   ADVANCED PARTICLE
                                   TECHNOLOGIES, INC.


                                   By: /s/ Eckardt C. Beck
                                      ------------------------------
                                      Name:  Eckardt C. Beck
                                      Title: Acting President


                                   CONVERSION TECHNOLOGIES
                                   INTERNATIONAL, INC.


                                   By: /s/ Eckardt C. Beck
                                      ------------------------------
                                      Name:  Eckardt C. Beck
                                      Title: Acting President


                                   VANGKOE INDUSTRIES, INC.


                                   By: /s/ Bo Gimvang
                                      ------------------------------
                                      Bo Gimvang
                                      President


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