EXHIBIT 2.0 OMG-Ferro Purchase Agreement

Exhibit 2.0

OMG-FERRO PURCHASE AGREEMENT

     THIS OMG-FERRO PURCHASE AGREEMENT (the “Agreement”) is made as of August 31, 2001 by and between OM Group, Inc., a Delaware corporation (“OMG”) and Ferro Corporation, an Ohio corporation (“Ferro”) (each of OMG and Ferro a “Party” and together, the “Parties”).

     WHEREAS, pursuant to that certain Purchase Agreement dated 23/24 April 2001 (the “OMG Purchase Agreement”) by and among OMG, dmc² Degussa Metals Catalysts Cerdec AG (“dmc²”) and Degussa AG (“Degussa”), dmc² agreed to sell to OMG, and OMG agreed to purchase, the business and operations of dmc²;

     WHEREAS, as part of the transactions contemplated by the OMG Purchase Agreement, Degussa, dmc² and OMG AG & Co. KG (“OMG KG”) entered into that certain Spin-off and Acquisition Agreement dated as of 11 June 2001 (the “OMG Spin-off Agreement”) whereby certain of the assets and liabilities of dmc² were spun-off to OMG KG with effect as of January 1, 2001;

     WHEREAS, as part of the transactions contemplated by the OMG Purchase Agreement as amended and restated, OMG and designated affiliates acquired on 10 August 2001 (i) all of the interests in OMG KG, and (ii) all of the shares of the non-German subsidiaries and other associated companies of dmc² (the “Transferred Businesses”) (the “OMG Closing”);

     WHEREAS, pursuant to that certain Heads of Agreement dated 23 April 2001 (the “Heads of Agreement”) by and between OMG and Ferro, the Parties have agreed that, as soon as practicable following the closing of the transactions contemplated in the OMG Purchase Agreement, OMG shall sell, transfer and assign to Ferro, and Ferro shall purchase and accept from OMG, certain of the Transferred Businesses as initially defined in the Heads of Agreement (each business being a “Ferro Business” and collectively “Ferro Businesses”), including all rights and obligations of OMG under the OMG Purchase Agreement related to the Ferro Businesses;

     WHEREAS, pursuant to the Heads of Agreement, the Parties agreed on many terms of the transfer of the Ferro Businesses, and this OMG-Ferro Purchase Agreement is intended to supplement and to be read in conjunction with and, except as expressly provided herein, not to supercede the Heads of Agreement; and

     WHEREAS, OMG and Ferro now wish to effect the sale, transfer and assignment of the Ferro Businesses;

     NOW THEREFORE, in consideration of the agreements herein contained, the parties agree as follows:

     1.     Transfer of the Ferro Businesses.

     1.1 Transaction Entities. Reference to “OMG” and “Ferro” (and “Party” or “Parties,” as appropriate throughout this Agreement) shall include, if the context permits, the affiliates of each of OMG and Ferro actually holding or intended to hold the Ferro Businesses.

     1.2 Sale. Subject to the provisions of this Agreement and the provisions of the Heads of Agreement, OMG hereby sells to Ferro and specifically to the Ferro affiliates designated on Annex 1.3(a) hereto, and Ferro hereby buys from OMG with effect as of the Closing Date (as defined in Section 6 below), all of OMG’s actual and beneficial interests in the Ferro Businesses. The sale of the Ferro Businesses shall include all rights and obligations attached to the Ferro Businesses as intended under the Heads of Agreement.

     1.3 Transfers.

     2.     Purchase Price.

     2.1 Purchase Price. The unadjusted purchase price for the Ferro Businesses shall be USD 524,493,000 (the “Purchase Price”), allocated among the Ferro Businesses as set forth on Annex 2.1 hereto.

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     2.2 Price Adjustment.

     2.3 Payments. On the Closing Date, Ferro, on behalf of the Ferro buyers listed on Annex 1.3(a), shall pay to OMG the Purchase Price via wire transfer of immediately available funds to such account or accounts as OMG shall have identified to Ferro at least three days prior to the Closing Date. Upon receipt of the Purchase Price, OMG shall deliver an executed Receipt in the form of Annex 2.3 hereto.

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     3.     Representations and Warranties.

     3.1 Representations and Warranties of Both Parties. Each of OMG and Ferro represents and warrants to the other that the representations and warranties contained in the Heads of Agreement are and will be true, accurate and complete as of the date hereof and as of the Closing Date.

     3.2 Representations and Warranties of OMG. OMG represents and warrants to Ferro that since the OMG Closing, and except to the extent Ferro has directed the operation of such businesses, OMG has operated the Ferro Businesses in accordance with the provisions of Section 5.7 of the Heads of Agreement and, to its knowledge, existing management at the Ferro Businesses has operated them in accordance with such provisions.

     4.     Agreements On Certain Subsidiaries.

     4.1 dmc² Istanbul and dmc² Portugesa. The parties agree that as soon as practicable after the date hereof they will or will cause their subsidiaries to enter into an agency agreement between each of dmc² Istanbul Degussa Megal Katalizör, Seramik Boyalari Ticaret Limited Sirketi (“dmc² Istanbul”) and Degussa Metais e Catalizadores e Cerâmicas Lda. (“dmc² Portugesa”) on one hand, and OMG or its designee, on the other hand, with respect to the OMG Businesses and Associated Assets operated by each of dmc² Istanbul and dmc² Portugesa, pursuant to which the employees of each company engaged historically in the operation of the OMG Businesses (understood by the parties to number not more than one or several employees in each company) shall remain employed by each company and shall sell products of the OMG Businesses owned by OMG. The parties agree further that title to the Closing Date inventory of the OMG Businesses and Associated Assets conducted by each company shall be transferred to OMG or its designee.

     4.2 dmc² China. The parties shall reach a fair agreement so that the assets of dmc² Degussa Metals Catalysts Cerdec China Limited (“dmc² China”) transferred on the date hereof pursuant to this Agreement to Ferro’s designee that are currently stored in the warehouse of dmc² China OMG shall remain stored in such warehouse for the period of time that is reasonably necessary for their removal from the warehouse through sale in the ordinary course of business. The Parties also agree to reach an equitable agreement for a sublease of facility space or agency agreement or other arrangement with the Ferro Businesses with respect to certain production or technical service assets that the Parties may agree not to remove from the dmc² China premises immediately. Between the date hereof and such transfers, OMG shall cause dmc² China to operate all aspects of the Ferro Businesses for the account and benefit of the Ferro Businesses.

     4.3 dmc² Taiwan. As soon as practicable after the date hereof, Ferro shall cause dmc² Taiwan to effect the transfer to OMG or its designee all of its right, title and interest in the OMG Businesses and Associated Assets operated or owned by it. On the date hereof the parties believe that such assets include the company’s employment relationship with one employee and inventory and stock. In addition, the parties agree that the employee of dmc² Taiwan who spends less than half of his time conducting sales for the OMG Businesses would train a designated OMG employee and provide to OMG information about customer contacts. Between the date

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hereof and such transfer date, Ferro shall cause dmc² Taiwan to operate all aspects of the OMG Businesses for the account and benefit of the OMG Businesses and Associated Assets.

     4.4 dmc² Italia and Italbras. The parties agree as follows with respect to the shares of dmc² Italia and its wholly-owned subsidiary, Italbras:

     5.     Covenants by Parties.

     5.1 Shared Facilities. Certain aspects of the separation of the Transferred Businesses into the Ferro Businesses and those OMG Businesses and Associated Assets retained by OMG in those sites at which both Ferro and OMG conduct business (listed on Annex 1.3(a)) will not be complete on the Closing Date. As set forth in Annex 1.3(a), as of and after the Closing Date the Parties and any other joint venture partners may enter into additional agreements for the split of such businesses. Such agreements shall also include, as necessary, definitive agreements for shared environmental, information technology, employee benefits and other services, as well as leases of real property.

     5.2 Good Faith Cooperation. The parties agree to cooperate with each other in good faith to effect the transfers contemplated herein, agreeing on tax-efficient structures for the transfers and assignments, lodging timely requests and applications with governmental and other bodies for the issuance or transfer of any permits and other authorizations, and entering into any additional contracts necessary to reflect the details and specific agreements contained in the Heads of Agreement or this Agreement as deemed necessary or appropriate by the Parties. The Parties shall observe with respect to all government regulatory authorities the procedures outlined in Section 5.6(c) of the Heads of Agreement for interactions with any Antitrust Authority.

     5.3 Further Assurance.

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     5.4 Third-Party Consents and Approvals.

     5.5 Employees and Employee Benefits.

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     5.6 Suretyship. OMG and Ferro each guarantees to the other the obligations of any nominee transferring or accepting transfer of the Ferro Businesses hereunder, including any indemnification obligations hereunder.

     5.7 Information Duty. Each Party shall give the other Party copies of all relevant documents and the opportunity to take part in all significant meetings and negotiations if that Party has a claim that materially affects both OMG and Ferro Businesses or if the claim relates to any of the Ferro Businesses. As between the Parties, any settlement, waiver or acknowledgement agreed on or declared by either Party shall not constitute proof of the factual or legal situation underlying the settlement, waiver or acknowledgement.

     5.8 Third Party Claims. Following the Closing Date, and upon written request of the other party, Ferro and OMG shall use all reasonable efforts to maintain and enforce any third-party indemnities or obligations available to either Ferro or OMG in respect of the Transferred Businesses, even if the indemnity or obligation being maintained or enforced would benefit only the other Party; provided that if one Party would receive benefit, that Party will bear the cost of pursuing the indemnity or claim.

     5.9 Non Competition. For a period of five (5) years from the Closing Date, each of OMG and Ferro agrees that it will not, and that it will cause its subsidiaries not to, develop, produce, market or sell (or assist any other person or entity to do so) products or services substantially similar to the products and services sold or provided as of the Closing Date by any of the Transferred Businesses acquired by the other of them for as long as the other holds a particular Transferred Business (a “Competing Business”). Nothing in this Section 4.9 will restrict the Parties from (i) owning, directly or indirectly, up to five percent (5%) of the outstanding shares of a publicly traded company engaged in a Competing Business, or (ii) from acquiring, directly or indirectly, an interest in an entity with a Competing Business if the revenues earned by such entity in the most recent fiscal year from the Competing Business do not exceed twenty-five percent (25%) of the total revenues earned by such entity for such period. The rights granted pursuant to this Section 4.9 shall not be assignable.

     5.10 Degussa License. OMG hereby grants to Ferro a sublicense to use the “Degussa License,” as defined in the OMG Purchase Agreement, pursuant to the terms set forth in Section 13.8 thereof.

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     5.11 Confidentiality. Each Party agrees to treat as confidential, except as otherwise required by law, any proprietary information about the Transferred Businesses acquired by the other Party, whether furnished to it by the other Party or by dmc² AG or Degussa, and whether furnished before or after the date of this Agreement and whether furnished in oral or written form (the “Information”). Notwithstanding the foregoing, Information may be disclosed by a Party to its officers, directors, employees, subsidiaries, affiliates and other agents or representatives (“Affiliates”) who (i) need to know the Information for the mutual business purposes contemplated in this Agreement or the Heads of Agreement and (ii) are informed of the confidential nature of the Information and agree to keep the Information confidential. The parties agree that the term “Information” does not include information which can be shown to have been (i) previously known on a nonconfidential basis by the disclosing Party, (ii) in the public domain through no fault of the disclosing Party or its Affiliates or (iii) independently developed by or on behalf of such Party without reference to the Information.

     5.12 Agency for Indemnification Purposes. Pursuant to Section 5.1 of the Heads of Agreement, OMG hereby appoints Ferro as its agent with full authority to pursue enforcement of OMG’s rights to indemnification under the OMG Purchase Agreement with respect to the Transferred Businesses.

     5.13 Insurance Coverage.

     6.     Conditions to Obligations of Parties. The obligations of OMG to consummate the transfer of the Ferro Businesses are subject to the satisfaction on or prior to the Closing Date of the conditions set forth in Section 5.1 hereof. The obligations of Ferro to consummate the transfer of the Ferro Businesses are subject to the satisfaction on or prior to the Closing Date of the conditions set forth in Section 5.2 hereof.

     6.1 OMG Closing Conditions. The obligations of OMG to consummate the transfer of the Ferro Businesses are subject to the satisfaction on or prior to the Closing Date of the following conditions:

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     6.2 Ferro Closing Conditions. The obligations of Ferro to consummate the transfer of the Ferro Businesses are subject to the satisfaction on or prior to the Closing Date of the following conditions:

     7.     Notices. Notices hereunder shall be provided in the manner described in the Heads of Agreement.

     8.     Governing Law and Resolution of Disputes.

     8.1 Governing Law. The validity, interpretation, and performance of this Agreement will be determined in accordance with the laws of the State of Ohio.

     8.2 Resolution of Disputes.

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     9.     Counterparts. This Agreement may be executed in two or more counterparts, each of which will be deemed an original, but all of which together shall constitute but one and the same instrument.

     10.     Headings. The headings, subheadings, and captions in this Agreement and in any exhibit hereto are for reference purposes only and are not intended to affect the meaning or interpretation of this Agreement.

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     11.     Exhibits and Annexes. The exhibits and annexes attached hereto and the other documents delivered pursuant hereto are hereby made a part of this Agreement as if set forth in full herein.

     12.     Entire Agreement. Except as otherwise provided herein, the OMG Purchase Agreement or in the Heads of Agreement, this Agreement and local transfer agreements and other agreements contemplated herein (“Transfer Instruments”) contain the entire agreement between the parties hereto with respect to its subject matter and supersedes all negotiations, prior discussions, agreements, arrangements, and understandings, written or oral, relating to the subject matter of this Agreement.

     13.     Supremacy of Agreement. Ferro and OMG each agree that each of the Transfer Instruments is made pursuant to, and subject to the limitations contained in, this Agreement, the OMG Purchase Agreement and the Heads of Agreement. In the event of a conflict between the terms of any Transfer Instrument and the terms of this Agreement, the terms of this Agreement shall govern, supersede and prevail.

     14.     Successors and Assigns. This Agreement will be binding upon OMG and Ferro and their respective successors and assigns. Notwithstanding the immediately preceding sentence, each party may assign its rights and delegate its duties under this Agreement to any of its subsidiaries or affiliated companies.

     15.     Severability. If any provision of this Agreement is held to be unenforceable, invalid, or void to any extent for any reason, that provision shall remain in force and effect to the maximum extent allowable, if any, and the enforceability and validity of the remaining provisions of this Agreement shall not be affected thereby.

     16.     No Third Party Beneficiaries. None of the parties hereto intends that any person not a party hereto shall be a third-party beneficiary of any provision of this Agreement and nothing contained herein shall be construed or deemed to confer any benefit or right upon any third party.

     IN WITNESS WHEREOF, each of the parties has caused this Agreement to be duly executed and delivered as of the day and year first above written.

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