EXHIBIT 10 (rr)


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                                   ----------

                              THE TIREX CORPORATION

                                   ----------

                            PURCHASE RIGHTS AGREEMENT

      Purchase Rights Agreement, made this 19th day of August 1998, between:

                      ENERCON America Distribution Limited
                      540 Tansy Lane
                      Westerville, Ohio 43081

                                               (the "Operator")

                                               and

                      The Tirex Corporation
                      740 St. Maurice, Suite 201
                      Montreal, Quebec
                      Canada H3C 1L5

                                               (the "Manufacturer")

      Whereas,  the  Manufacturer  and  the  Operator  are  parties  to  certain
equipment lease and purchase  agreements,  of even date herewith (the "Equipment
Lease and  Purchase  Agreements"),  between the  Manufacturer  and the  Operator
respecting the sale by the  Manufacturer and the Purchase by the Operator of the
"Purchased  Equipment" and the operating  lease,  between the  Manufacturer,  as
lessor,  and the Operator,  as lessee (the  "Operating  Lease"),  respecting the
"Leased  Equipment",  as those terms are defined in the said Equipment Lease and
Purchase Agreements.

      Whereas,  Section 4 of each of the respective Equipment Lease and Purchase
Agreements contains the terms and provisions of the respective Operating Leases,
with  Subparagraphs  4.2.2  (b) of  each  of such  Agreements  providing  to the
Operator  the sole and  exclusive  right to extend  the  terms of the  Operating
Leases yearly,  on a perpetual  basis, at a reduced rental rate, or to terminate
the said Operating Leases upon 90 days written notice to the Manufacturer.

      Whereas,  the Operator wishes to have, and the  Manufacturer has agreed to
grant to the Operator,  the right to purchase the Leased  Equipment in the event
that a voluntary or involuntary petition is filed by or against the Manufacturer
under Chapter 7 of the United States  Bankruptcy laws having for its purpose and
adjudication  of  the  Manufacturer  a  bankrupt  and  the  liquidation  of  the
Manufacturer's assets pursuant thereto.

      Now, Therefore,  in consideration for the premises and the mutual promises
made herein and in the Equipment Lease and Purchase Agreements,  it is agreed as
follows:


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1.    Definitions

      1.1 "Manufacturer" shall mean The Tirex Corporation and its successors and
assigns.

      1.2 "Operator"  shall mean ENERCON  America  Distribution  Limited and all
other  corporations,  partnerships,  or  other  entities,  now or in the  future
controlled  by, under common  control  with, or in control of,  ENERCON  America
Distribution Limited, jointly and severally.

      1.3 All other  Capitalized  terms used  herein and not  otherwise  defined
shall have the respective meanings attributed thereto in the Equipment Lease and
Purchase Agreements.

2.    Operator's Right to Purchase Leased Equipment

      2.1  To  the  extent  permitted  under  applicable   bankruptcy  laws  and
regulations,  the  Manufacturer  hereby  grants  to the  Operator  the  right to
purchase  the Leased  Equipment  in the event that a  voluntary  or  involuntary
petition is filed by or against the  Manufacturer  under Chapter 7 of the United
States   Bankruptcy  laws  having  for  its  purpose  the  adjudication  of  the
Manufacturer  as a bankrupt and the  liquidation  of the  Manufacturer's  assets
pursuant thereto, in which event:

      (a)   The   Manufacturer   shall,   within  five  business  days  of  such
            occurrence, give written notice thereof to the Operator;

      (b)   The  Operator  shall,  within five  business  days of receipt of the
            above described  notice,  advise the Manufacturer  whether or not it
            wishes to purchase the Leased Equipment.

3.    Purchase Price

      The purchase price for the Leased  Equipment  shall be the greater of: (i)
seven hundred fifty  thousand  United States  dollars (US $750,000) less $10,000
for each monthly rental  payment  (including  $12,500  initial term payments and
$6,250 extended term payments) that Operator shall  theretofore  have paid under
the Operating Lease; or (ii) $50,000.

6.    Assignment

      6.1 This  Purchase  Rights  Agreement  may not be assigned by the Operator
except as part of the assignment of the Equipment Lease and Purchase  Agreement,
which may only be  assigned  pursuant  to the  express  written  consent  of the
Manufacturer,  and any such  assignment  shall not relieve  the  Operator of its
obligations hereunder unless expressly waived in writing by the Manufacturer.

      6.2 This Purchase Rights Agreement may be transferred,  assigned, pledged,
or  hypothecated  by the  Manufacture  as part of the  sale of its  business  or
otherwise.


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7.    Notices

      All notices required or permitted to be given hereunder shall be mailed by
certified mail, or delivered by hand or by recognized  overnight  courier to the
party to whom such notice is required or permitted to be given  hereunder at the
address  set forth  above for such  party,  in all cases with  written  proof of
receipt  required.  Any such  notice  shall be deemed to have  been  given  when
received by the party to whom notice is given, as evidenced by written and dated
receipt of the  receiving  party.  Either  party may change the address to which
notice to it is to be  addressed,  by  written  notice to the  other  party,  as
provided herein.

8.    Binding Effect.

      8.1 This Purchase Rights  Agreement shall bind and inure to the benefit of
the parties hereto and their  respective legal  representatives,  successors and
assigns,  provided,  however,  that this  Agreement  cannot be  assigned  by the
Operator except in accordance with Section 6.1 hereof.  Nothing herein expressed
or implied  is  intended  or shall be  construed  to confer  upon or to give any
person,  firm or corporation  other than the parties hereto and their respective
legal representatives, successors and assigns any rights or benefits under or by
reason of this Agreement.

9.    Further Assurances

      At any time, and from time to time, after the execution of this Agreement,
each party will execute such additional  instruments and take such action as may
be  reasonably  requested by the other party to confirm or perfect  title to any
property transferred hereunder or otherwise to carry out the intent and purposes
of this Agreement.

10.   Waiver

      Any  failure  on the part of any party  hereto  to comply  with any of its
obligations,  agreements or conditions hereunder may be waived in writing by the
party to whom such compliance is owed.

11.   Brokers

      Neither  party has  employed  any  brokers or finders  with regard to this
Agreement, unless otherwise described in writing to all parties hereto.

12.   Headings

      The section and  subsection  headings in this  Agreement  are inserted for
convenience  only and shall not affect in any way the meaning or  interpretation
of this Agreement.

13.   Governing Law

      This Agreement shall be governed by the laws of the State of Delaware.


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14    Entire Agreement

      This Agreement and the premises and mutual promises in the Equipment Lease
and Purchase  Agreement  constitute the entire agreement of the parties covering
everything  agreed upon or understood  with respect to the Operator's  rights to
purchase  the  Leased  Equipment.  There  are  no  oral  promises,   conditions,
representations,  understandings,  interpretations  or  terms  of  any  kind  as
conditions or inducements to the execution hereof.

15.   Severability

      If any part of this Agreement is deemed to be unenforceable the balance of
this Agreement shall remain in full force and effect.

16.   Publicity

      All  notices  to third  parties  and all other  publicity  concerning  the
transactions  contemplated  by this  Agreement  shall be  subject  to the  prior
approval of counsel to the Manufacturer.

17.   Counterparts

      This Agreement may be executed in any number of  counterparts  and by each
party on a separate  counterpart,  each of which when so executed and  delivered
shall be an original, but all of which together shall constitute one Agreement.

      In Witness  Whereof,  the parties hereto have caused this Purchase  Rights
Agreement to be executed the day and year first above written.

whatsoever.

                                      ENERCON AMERICA DISTRIBUTION LIMITED

                                      By /s/ David L. Holmes
                                         ---------------------------------------
                                             David L. Holmes

                                      THE TIREX CORPORATION

                                      By /s/ Terence C. Byrne
                                         ---------------------------------------
                                             Terence C. Byrne, President


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