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                                                                   Exhibit 4.5



















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                              AMENDED AND RESTATED
                              --------------------
                                CREDIT AGREEMENT
                                ----------------

                    THIS AMENDED AND RESTATED CREDIT AGREEMENT is entered into
as of this 2nd day of May, 1996, between Chemi-Trol Chemical Co., an Ohio 
corporation ("Borrower"), and The Fifth Third Bank of Northwestern Ohio, N.A. 
("Bank").

                    ARTICLE I. DEFINITIONS
                               -----------

                    For purposes of this Agreement, the following capitalized
terms shall have the following meanings:

                    1.1 AGREEMENT shall mean this Loan Agreement as originally
executed and as the same may from time to time be amended or supplemented.

                    1.2 BUSINESS DAY shall mean a day when commercial banks are
open for business in Findlay, Ohio.

                    1.3 CLOSING Date shall mean the date of the making of the
Loan.

                    1.4 COLLATERAL shall mean all accounts, accounts receivable,
contract rights, lease rights, instruments, documents, chattel paper, and all
obligations in any form arising out of the sale or lease of propane tanks or
other goods or inventory of Borrower or the rendition of services by Borrower;
all general intangibles, choses in action, obligations or indebtedness owed to
Borrower in connection with the foregoing; guaranties, letters of credit and
other security for any of the above; all merchandise returned to or reclaimed by
Borrower in connection with the foregoing; and all of Borrower's inventory and
work-in-process, now owned or hereafter acquired; all books and records
(including computer programs, tapes and data processing software) evidencing an
interest in or relating to the above; and all proceeds and products thereof and
all rents, revenues, issues and profits arising therefrom.

                    1.5 COLLATERAL DOCUMENTS shall mean the Notes, Security
Agreement and Financing Statements.

                    1.6 DOLLARS AND $ shall mean United States dollars or such
coin or currency of the United States of America as at the time of payment shall
be legal tender for the payment of public and private debts in the United
States.

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                    1.7 FINANCING STATEMENTS shall have the meaning provided in
Section 4.1(c) hereof.

                    1.8 Loans shall have the meaning provided in Section 2.4
hereof.

                    1.9 Notes shall have the meaning set forth in Section 2.4
hereof.

                    1.10 SECURITY AGREEMENT shall have the meaning set forth in
Section 4.1(b) hereof.

                    ARTICLE II. LOAN

                    2.1 THE LOAN. Subject to the terms and conditions of this
Agreement, Bank agrees to make loans ("Revolving Loans") to Borrower from the
date of this Agreement to, but not including May 2, 1997 ("Termination Date"),
at such times as Borrower may request, which Revolving Loans may be borrowed,
repaid and reborrowed; provided, however, that the aggregate unpaid principal
amount of the Revolving Loans shall at no time exceed Fifteen Million Dollars
($15,000,000.00). All outstanding Revolving Loans shall be secured by the
Collateral and shall be evidenced by a promissory note substantially in the form
of Exhibit A attached hereto. All notes evidencing revolving credit loans shall
be collectively referred to herein as the "Revolving Notes." Each of the
Revolving Notes shall be dated as of the date of each particular Revolving Loan.

                    2.2 INTEREST ON REVOLVING LOANS. The outstanding principal
amount of the Revolving Loans shall bear interest from the date thereof until
due and payable at an annual rate equal to the Bank's Prime Rate as in effect
from time to time less one-half percent (.50%). Interest shall be calculated on
the basis of a year of 360 days and charged for the actual number of days
elapsed.

                    2.3 PAYMENT OF REVOLVING LOANS. Interest on the Revolving
Loans shall be payable on demand, and if no demand has been made, in arrears
monthly on the second day of each month, commencing on June 2, 1996 and ending
on May 2, 1997. The aggregate unpaid principal amount of, and accrued and unpaid
interest on, all Revolving Loans shall be paid in full by Borrower on or before
May 2, 1997.

                    2.4 CONVERSION TO TERM LOANS. On or before May 2, 1997,
Borrower shall have the right to convert up to a maximum principal amount of
Seven Million Dollars ($7,000,000.00) of the Revolving Loans to Term Loans (the
"Term Loans"). Revolving Loans may only be converted to Term Loans in the event
that sufficient Collateral, as determined in the Bank's discretion, is provided
to secure each Term Loan. The principal amount of each Term Loan shall be repaid
in 36 to 60 equal installments due on the first day of each





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calendar month with the first such payment being due on the first day of the
month following the month the particular election is made to convert the
Revolving Loan into a Term Loan. The number of payments on each Term Loan shall
match the term of the account, note or lease given as Collateral at the time of
conversion. Borrower shall duly issue and deliver to Bank a note in the form of
Exhibit B (each a "Term Note" and collectively "Term Notes") in the principal
amount of the particular Term Loan. For purposes of this Agreement, the
Revolving Loans and the Term Loans shall be collectively referred to as the
"Loans", and the Revolving Notes and the Term Notes shall be collectively
referred to as the "Notes". The credit line available through the Revolving
Loans shall decrease dollar for dollar with the amount of the Term Loans.

                    2.5 INTEREST ON TERM Loans. The outstanding principal amount
of each Term Loan shall bear interest from the date thereof until due and
payable at an annual rate equal to the yield for United States Treasury
obligations having a maturity date equal to the maturity date of the Term Loans
(or the next closest maturity date thereafter) plus two hundred (200) basis
points. Interest shall be calculated on the basis of a year of 360 days and
charged for the actual number of days elapsed.

                    2.6 LATE CHARGE. Any payment on any of the Notes which is
more than ten (10) days overdue will be assessed a late charge equal to five
percent (5%) of the overdue payment.

                    2.7 DEFAULT RATE OF INTEREST. If any payment on any of the
Notes is more than thirty (30) days overdue, or in the event any other default
occurs under this Agreement or any of the Collateral Documents, Bank shall have
the right, without notice, to increase the annual rate of interest on the entire
unpaid principal balance to four percent (4%) above the interest rate that would
otherwise be in effect until the entire amount of principal and/or interest then
due has been paid in full or the default is cured.

                    2.8 SECURITY. The Revolving Loans and the Term Loans shall
be secured by a first security interest in the Collateral, which shall be
evidenced by the Security Agreement and Financing Statements. In addition, as
the granting of the Loans is an amendment and restatement of the Loans granted
in the Credit Agreement between the parties dated April 1, 1994, as the same has
been amended by an Amendment to Credit Agreement dated as of May 1, 1995, and a
Second Amendment to Credit Agreement dated as of June 12, 1995, the financing
statements executed in connection with the Security Agreement dated May 1, 1995
between the parties also secure the Revolving Loans and the Term Loans.

                    ARTICLE III. REPRESENTATIONS AND WARRANTIES OF BORROWER

                    Borrower hereby warrants and represents to Bank the
following:





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                    3.1 ORGANIZATION AND QUALIFICATION. The Borrower is duly
organized and validly existing under the laws of the State of Ohio, has the
power and authority to carry on its business and to enter into and perform this
Agreement and is qualified and licensed to do business in each jurisdiction in
which such qualification or licensing is required and where failure to qualify
would have a material adverse effect on the financial condition or operations of
Borrower.

                    3.2 DUE AUTHORIZATION. The execution, delivery and
performance by Borrower of this Agreement, the Security Agreement, Financing
Statements and the Notes have been duly authorized by all necessary corporate
action, and to the best of Borrower's knowledge will not contravene any law or
any governmental rule or order binding on Borrower, or the articles of
incorporation or bylaws of Borrower, nor violate any agreement or instrument by
which Borrower is bound nor result in the creation of a Lien on any assets of
Borrower except the Lien to Bank granted in the Security Agreement.

                    3.3 LITIGATION. There are no material suits or proceedings
pending or threatened (to the best of Borrower's knowledge) against or affecting
Borrower, and no proceedings before any governmental body pending or threatened
(to the best of Borrower's knowledge) against Borrower not previously disclosed
to Bank.

                    3.4 LAWS AND TAXES. To the best of Borrower's knowledge,
Borrower is in material compliance with all laws applicable to it, has filed all
required tax returns and has paid all taxes shown to be due and payable on those
returns.

                    3.5 FINANCIAL CONDITION. All financial information relating
to Borrower which has been or may hereafter be delivered to Bank is true and
correct in all material respects and all audited financial statements have been
prepared in accordance with generally accepted accounting principles (where
applicable to such financial information) consistently applied. Borrower does
not have any material obligations or liabilities of any kind not disclosed in
that financial information, and there has been no material adverse change in the
financial condition of Borrower since the submission of the most recent
financial information to Bank.

                    ARTICLE IV. CONDITIONS PRECEDENT

                    4.1 EXTENSION OF CREDIT. The obligation of Bank to make any
Loan hereunder is subject to the fulfillment to Bank's satisfaction of each of
the following conditions prior to the making of such Loan:

                    (a) PROMISSORY NOTES. Bank shall have received the Notes,
                    duly executed and delivered by Borrower;



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                    (b) SECURITY AGREEMENT. Bank shall have received an Amended
                    and Restated Security Agreement ("Security Agreement"),
                    duly executed and delivered by Borrower, in a form approved
                    by Bank;

                    (c) FINANCING STATEMENTS. Bank shall have received executed
                    copies of proper financing statements (Form UCC-1), in form
                    and substance satisfactory to Bank, to be duly filed under
                    the Uniform Commercial Code in all jurisdictions as may be
                    necessary, or in Bank's opinion, desirable to perfect Bank's
                    security interests created under the Security Agreement, and
                    all filings, recordings and other actions that are necessary
                    or advisable, in the opinion of Bank, in order to establish,
                    protect, preserve and perfect Bank's security interests and
                    liens as legal, valid and enforceable first security
                    interests and liens in such collateral, and Bank shall have
                    received evidence thereof in form and substance satisfactory
                    to it;

                    (d) UCC SEARCH RESULTS. Bank shall have received certified
                    copies of Requests for Information (Form UCC-11) from the
                    appropriate governmental entities listing all other
                    effective financing statements which name Borrower as debtor
                    and which are filed in the jurisdictions referred to in
                    paragraph (c), together with copies of all such other
                    financing statements (none of which shall cover the
                    Collateral purported to be covered by the Security
                    Agreement);

                    (e) ORGANIZATIONAL DOCUMENTS. Bank shall have received a
                    certificate of good standing from the Ohio Secretary of
                    State, dated within thirty (30) days of closing.

                    (f) CORPORATE RESOLUTION. The Borrower shall have furnished
                    to Bank a statement of the Borrower's Secretary, certifying
                    the resolutions of Borrower's board of directors authorizing
                    and approving the borrowing provided for herein, and setting
                    forth the officers authorized to execute this Agreement and
                    all documents connected herewith.

                    (g) ADDITIONAL DOCUMENTS. Bank shall have received from the
                    Borrower such additional documents as reasonably deemed
                    necessary by Bank in order for Bank to deem itself secure.

                    ARTICLE V. AFFIRMATIVE COVENANTS
                               ---------------------

                    Borrower covenants that until the payment in full of the
Loans and fulfillment of all of its obligations hereunder, Borrower shall comply
with the following covenants, any of which may be waived by Bank at any time:



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                    5.1 ACCOUNTING RECORDS. Borrower shall maintain adequate
books and accounts in accordance with generally accepted accounting principles
consistently applied, and permit any representative of Bank, at any reasonable
time, upon reasonable notice, to inspect, audit and examine such books and
inspect any of its properties and shall furnish Bank with all information
regarding the business and its finances promptly upon Bank's request.

                    5.2 PROCEEDS. Borrower will use the proceeds of the Loans
for general corporate purposes, and will furnish Bank such evidence as it may
reasonably require with respect to such use.

                    5.3 FINANCIAL STATEMENTS. As long as any portion of the
Loans remains outstanding, Borrower will furnish Bank:

                    (a) Within forty-five (45) days after the end of each
                    quarter, a copy of its financial statements for that quarter
                    and for the year to date in a form reasonably acceptable to
                    Bank, prepared and certified as complete and correct,
                    subject to changes resulting from year-end adjustments, by
                    the principal financial officer of Borrower.

                    (b) Within ninety (90) days after the end of each fiscal
                    year, a copy of its financial statements for that year
                    audited by a firm of independent certified public
                    accountants acceptable to Bank (which acceptance will not be
                    unreasonably withheld), and accompanied by a standard audit
                    opinion of such accountants without significant
                    qualification.

                    (c) Upon request, copies of all federal, state and local
                    income tax returns and such other information as Bank may
                    reasonably request.

                    5.4 FILINGS. Borrower shall from time to time record,
register and file all such notices, statements and other documents and take such
other steps, including, but not limited to, the amendment of the financing
statements prepared under the Security Agreement, as may be necessary or
advisable to render fully valid and enforceable under all applicable laws the
rights, liens and priorities of Bank with respect to all security from time to
time furnished under this Agreement or the Security Agreement or intended to be
so furnished, in each case in such form and at such times as shall be
satisfactory to Bank.

                    5.5 REORGANIZATION. Borrower shall notify Bank in advance of
any change in its name and shall not participate in any merger, consolidation or
reorganization without prior written approval of Bank, which approval shall not
be unreasonably withheld.




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                    5.6 ADVANCES; GUARANTIES. Borrower shall not advance any
monies to, guaranty any obligation of or make any payment for the benefit of
any other person or entity other than in the ordinary course of business.

                    5.7 DEPOSITS. Borrower shall maintain its primary deposit
accounts with Bank during the term hereof.

                    5.8 PLEDGE OR ENCUMBRANCE OF ASSETS. Borrower will not
create, incur, assume or permit to exist any further lien in any of the
Collateral.

                    5.9 DELIVERY OF NOTES AND LEASES. Borrower shall deliver to
Bank and Bank shall hold all notes received from Borrower's customers for
products sold or services rendered which are pledged as Collateral. In addition,
Borrower shall provide Bank with copies of all customer leases which are pledged
as Collateral.

                    5.10 QUARTERLY REVIEW. Bank shall have the right to review
the Collateral on a quarterly basis to be assured of its adequacy. Borrower
shall give Bank access to all Collateral and associated records in order to
allow Bank to conduct its review. In the event that Bank determines, upon any
quarterly review, that the Collateral is insufficient to support its
corresponding Term Loan, Borrower shall be required to pay down the Term Loan
until the value of the collateral is equal to or greater than the Loan balance,
or give additional Collateral to Bank which is sufficient to assure that the
Collateral value equals or is greater than the corresponding Term Loan balance.

                    5.11 FINANCIAL LEVELS AND RATIOS. Borrower shall maintain
and end each fiscal year with the following financial levels and ratios: (a)
Debt to Worth not to exceed 1.8:1; Minimum Tangible Net Worth of not less than
$18,500,000.00; Working Capital of not less than $13,000,000.00; Current Ratio
of not less than 1.5:1.

                    ARTICLE VI. DEFAULT

                    6.1 DEFAULT. If Borrower fails to comply with any of the
covenants made by Borrower in this Agreement or any of the Collateral
Documents, or if any of the conditions of Article IV fail to be satisfied, or
if at any time any representation or warranty made by Borrower herein or in any
other instrument or document delivered to Bank in connection herewith shall be
incorrect, then in any such event, all obligations of Bank to make any further
Loan advances shall cease (if Bank so elects) and the Notes, at Bank's option,
shall become immediately due and payable.




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                    6.2 REMEDIES. Upon Borrower's default, Bank may avail itself
of any and all remedies available to it at law or in equity, and all such
remedies shall be cumulative and none shall be deemed exclusive of any other;
further, and not in limitation of the foregoing, Bank may terminate this
Agreement and demand full payment of the Borrower's indebtedness to it; and may
utilize any remedy available to it under the terms and provisions of the
Collateral Documents.

                    ARTICLE VII. MISCELLANEOUS

                    7.1 WAIVERS. Any waiver, permit, consent or approval by Bank
of any breach of any provision, condition or covenant of this Agreement or the
Collateral Documents must be in writing and shall be effective only to the
extent it is set forth in writing. No waiver of a specific breach shall operate
as a waiver of any other or future breach.

                    7.2 FAILURE OR DELAY. No failure or delay on the part of
Bank in the exercise of any power, right or privilege under this Agreement or
the Collateral Documents shall operate as a wavier thereof, nor shall any
single or partial exercise of any such power, right or privilege preclude other
or further exercise of any other power, right or privilege.

                    7.3 CUMULATIVE RIGHTS. All rights and remedies existing
under this Agreement and the Collateral Documents are cumulative to, and not
exclusive of, any rights or remedies otherwise available under applicable law.

                    7.4 SEVERABILITY. Any provision of this Agreement or the
Collateral Documents which is prohibited or unenforceable in any jurisdiction
shall be, only as to such jurisdiction, ineffective to the extent of such
prohibition or unenforceable, but all the remaining provisions of this
Agreement and the Collateral Documents shall remain valid.

                    7.5 SUCCESSORS AND ASSIGNS. This Agreement shall be binding
upon and shall inure to the benefit of Bank and Borrower and their respective
successors and assigns; provided, however, that Borrower may not assign or
transfer its rights or obligations under this Agreement without the prior
written consent of Bank.

                    7.6 NOTICES. Any notice which either party may be required
or may desire to give to the other party under any provision of this Agreement
or the Collateral Documents shall be in writing and shall be deemed to have been
given or made when deposited in the mail, postage prepaid, and addressed as
follows:




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To Borrower:         Chemi-Trol Chemical Co.
                     2776 C.R. 69
                     Gibsonburg, Ohio 43431
                     Attention: Robert W. Woolf, President

To Bank:            The Fifth Third Bank of Northwestern Ohio, N.A. 
                     337 South Main Street
                     Findlay, Ohio 45840
                     Attention: Commercial Lending Department

Bank and Borrower may change the addresses to which all notices, requests and
other communications are to be sent by giving written notice of such address
change to the other party in conformity with this paragraph, but such change
shall not be effective until notice of such change has been received by the
other party.

                    7.7 COSTS, EXPENSES AND ATTORNEYS' Fees. Borrower shall be
responsible and reimburse Bank for all costs and expenses, including, but not
limited to, reasonable attorneys' fees and expenses (which counsel may be Bank
employees) expended or incurred by Bank in the preparation, negotiation,
enforcement and/or amendment of this Agreement or the Collateral Documents, in
collecting any sum which becomes due Bank on the Notes, or under this Agreement
or the Collateral Documents, or in the protection, preservation or enforcement
of any rights of Bank in connection with this Agreement or the Collateral
Documents. Borrower also shall be responsible for all other reasonable costs and
expenses incurred in connection with the Loans, including but not limited to:
loan fees; insurance premiums; UCC, judgment and lien search costs; and
recording costs. Borrower shall promptly reimburse Bank for all such costs and
expenses paid by Bank.

                    7.8 GOVERNING LAW. The validity, construction and effect of
this Agreement and the Collateral Documents shall be governed by the laws of the
State of Ohio.

                    7.9 COMPLETE AGREEMENT. This written Agreement, together
with the exhibits to this Agreement and the Collateral Documents, is intended by
the parties as a final expression of their agreement and is intended as a
complete statement of the terms and conditions of their agreement. This
Agreement can only be amended in a writing executed by both parties.




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                    IN WITNESS WHEREOF, Bank and Borrower have caused this
Agreement to be duly executed on the day and year first written above.


                                  THE FIFTH THIRD BANK OF       
                                  NORTHWESTERN OHIO, N.A.       
                                                              
                                  By: /s/ Jeffrey C. Shrader                    
                                      --------------------------- 
                                  Title: Vice President         
                                         ------------------------ 
                                                              
                                  CHEMI-TROL CHEMICAL CO.       
                                                              
                                  By: /s/ Arthur F. Doust
                                      --------------------------- 
                                  Title: C.E.O.                       
                                         ------------------------ 
                                                              
                                  By: /s/ Robert W. Woolf           
                                      --------------------------- 
                                  Title: President
                                         ------------------------              
                                








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