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     10.28  Loan Agreement and $80,000 Promissory Note dated November 3, 1997 
            between Registrant and First Union National Bank of Tennessee


                                PROMISSORY NOTE
$80,000.00                                                  November 3, 1997


Kyzen Corporation, a Utah Corporation
430 Harding Industrial Drive
Nashville, Tennessee 37211
(Individually  and collectively "Borrower")

First Union National Bank
First Union Tower
150 4th Avenue North
Nashville, Tennessee 37219
(Hereinafter referred to as the "Bank")

Borrower promises to pay to the order of Bank, in lawful money of the United
States of America, at its office indicated above or wherever else Bank may
specify, the sum of Eighty Thousand and No/100 Dollars ($80,00.00) or such sum
as may be advanced and outstanding from time to time with interest on the unpaid
principal balance at the rate and on the terms provided in this Promissory Note
(including all renewals, extensions or modifications hereof, this "Note")

SECURITY. Borrower has granted Bank a security interest. in the collateral
described in the loan Documents, including, but not limited to, (i) personal
property collateral described in that certain Security Agreement of even date
herewith and (ii) That certain Assignment of Money Market investment
Account/Instrument between Bank am Kyzen Corporation dated November 13, 1997.

INTEREST RATE. Interest shall accrue on the unpaid principal balance of this
Note from the date hereof at the rate of Bank's Prime Rate plus 1.0% as that
rate may change from time to time in accordance with changes in the Bank's Prime
Rate ("Interest Rate"). Bank's Prime Rate shall be that rate announced by Bank
from time to time as its Prime Rate and is one of several interest rate bases
used by Bank. Bank lends at both above and below Bank's prime Rate, and Borrower
acknowledges that Bank's Prime Rate is not represented or intended to be the
lowest or most favorable rate of interest offered by Bank.

DEFAULT RATE. In addition to other rights contained in this Note, if a Default
(defined herein) occurs and as long as Default continues all outstanding
Obligations shall bear interest at the Interest Rate plus 3% ("Default Rate").
The Default Rate shall also apply from acceleration until the Obligations or any
judgment is paid in full,

INTEREST AND FEE(S) COMPUTATION. (Actual/360). Interest and fees, if any, shall
be computed on the basis of a 360 day year for the actual number of days in the
applicable period ("Actual/360 Computation"). The Acnral/360 computation
determines the annual effective yield by taking the stated (nominal) rate for a
year's period and there dividing said rate by 360 to determine the daily
periodic rate to be applied for each day in the applicable period. Application
of the Actua1/360 Computation produces an annual effective rate exceeding that
of the nominal rate.

REPAYMENT TERMS. Note shall be due and payable in consecutive monthly payments
of principal and interest in the amount of $2,010.00 commencing on December 13,
1997, and on the same day of each month thereafter until fully paid. In any
event, all principal and accrued interest shall be due and payable on October,
15, 2001.

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Scheduled Payment Adjustment (for variable interest rate loans only). At Bank's
option and with notice to Borrower, the scheduled payment amount will increase
as is necessary (i) to pay all accruals of interest for the periodic and
previous periods and (ii) to maintain principal repayment according to the
amortization that would have occurred if the Interest Rate in effect on the date
of this Note had remained constant. The increased payment shall remain in effect
for as long as the original scheduled payment amount is insufficient to pay
accrued interest and principal and shall be further adjusted upward or downward
to reflect changes in the variable interest rate. The scheduled payment amount
will not be reduced below the original scheduled payment amount.

APPLICATION OF PAYMENTS. Monies received by Bank from any source for application
toward payment of the Obligations shall be applied to accrued interest and then
to principal. If a Default occurs, monies may applied to the Obligation in any
manner or order deemed appropriate by Bank.

If any payment received by Bank under this Note or other Loan Documents is
rescinded, avoided or for any reason returned by Bank because of any adverse
claim or threatened action, the returned payment shall remain payable as an
obligation of all persons liable under this Note or other Loan Documents as
though such payment has not been made.

LOAN DOCUMENTS AND OBLIGATIONS. The term "Loan Documents" used in this Note and
other Loan Documents refers to all documents executed in connection with the
loan evidenced by this Note and any prior notes which evidence all or any
portion of the loan evidenced by this Note, and any letters of credit issue
pursuant to any loan agreement executed in connection with this Note, any
applications for such letter of credit and any other documents executed in
connection therewith, and may include, without limitation, a commitment letter
that survives dosing, a loan agreement, this Note, guarantee agreements,
security agreements, security instruments, financing statements, mortgage
instruments, letters of credit and any renewals or modifications, whenever any
of the foregoing are exercised, but does not include swap agreements (as defined
in 11 U.S.C. - 101).

The term "Obligations" used in this Note refers to any and all indebtedness and
other obligations under this Note, all other obligations under any other Loan
Documents, and an obligations under any swap agreements as defined in 11 U.S.C.
- 101 between Borrower and Bank whenever executed.

LATE CHARGE. If any payments are not timely made, Borrower shall also pay to
Bank a late charge equal to 5% of each payment past due for 15 or more days.

Acceptance by Bank of any late payment without an accompanying late charge shall
nor be deemed a waiver of Bank's right to collect such late charge or to collect
a late charge for any subsequent late payment received.

ATTORNEYS' FEES AND OTHER COLLECTION COSTS. Borrower shall pay an of Bank's
reasonable expenses incurred to enforce or collect any of the Obligations,
including, without limitation, reasonable arbitration, paralegals' attorneys'
and experts' fees and expenses, whether incurred without the commencement of a
suit in any trial, arbitration, or administrative proceeding, or in any
appellate or bankruptcy proceeding.

USURY. Regardless of any other provision of this Note or other Loan Documents,
if for any reason the effective interest should exceed the maximum lawful
interest, the effective interest shall be deemed reduced to and shall be such
maximum lawful interest, and (i) the amount which would be excessive interest
shall be applied to the reduction of the principal balance of this Note and not
to the payment of interest, and (ii) if the loan evidenced by this Note has been
or is thereby paid in full, the excess shall be returned to the party paying
same, such application to the principal balance of this Note or to the refunding
of excess to be a complete settlement and acquittance thereof.

DEFAULT. If any of the following occurs a default ("Default") under this Note
shall exist: NONPAYMENT; NONPERFORMANCE. The failure of timely payment or
performance of the Obligations or Default (however denominated) under this Note
or any other Loan Documents. FALSE WARRANTY. A warranty or representation made
or deemed mate in the :Loan Documents or furnished Bank in connection with the
loan evidenced by this 

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Note proves materially false, or if of a continuing nature, becomes materially
false. CROSS DEFAULT. At Bank's option, any default in payment a performance of
any obligation under any other loans, contract; or agreements of Borrower, any
Subsidiary or Affiliate of Borrower, any general partner of the holder(s) of the
majority ownership interests of Borrower with Bank or its affiliate ("Affiliate"
shall have the meaning at defined in 11 U.S.C. - 101, except that the term
"debtor" therein shall be substituted by the term "Borrower" herein;
"Subsidiary' shall mean any corporation which more than 50% of the issued and
outstanding voting stock is owned directly or indirectly by Borrower).
CESSATION; BANKRUPTCY. The death of, appointment of guardian for, dissolution
of, termination of existence of , loss of good standing status by, appointment
of , receiver for, assignment for the benefit of creditors of, or commencement
of any bankruptcy or insolvency proceeding by or against the Borrower, its
Subsidiaries or Affiliates, if any, or any general partner of or the holder(s)
of the majority ownership interests of Borrower, or any party to the Loan
Documents. MATERIAL CAPITAL STRUCTURE OR BUSINESS ALTERATION. Without prior
written consent of Bank, (I) a material alteration in the kind or type of
Borrower's business or that of Borrower's Subsidiaries or Affiliates, if any;
(ii) the sale of substantially all of the business or assets of Borrower, any of
Borrower's Subsidiaries Or Affiliates or guarantor or a material portion (10% or
more) of such business or assets if such a sale is outside the ordinary course
of business of Borrower, or any of Borrower's Subsidiaries or Affiliates or any
guarantor or more than 50% of the outstanding stock or voting power of or in any
such entity in a single transaction or a series of transactions; (iii) the
acquisition of substantially all of the business or assets or more than 50% of
the outstanding stock or voting power of any other entity; or (v) should any
Borrower, or any of Borrower's Subsidiaries or Affiliates or guarantor enter
into any merger or consolidation.

REMEDIES UPON DEFAULT. If a Default occurs under this Note or any Loan
Documents, Bank may at any time thereafter, take the following actions: BANK
LIEN. Foreclose its security interest or lien against Borrower's accounts
without notice. ACCELERATION UPON DEFAULT. Accelerate the maturity of this Note
and all other Obligations and all of the Obligations shall be immediately due
and payable. CUMULATIVE. Exercise any right and remedies as provided under the
Note and other Loan Documents, or as provided by law or equity.

FINANCIAL AND OTHER INFORMATION. Borrower shall deliver to Bank such information
as Bank may reasonably request from time to time, including without limitation,
financial statements and information pertaining to Borrower's financial
condition. Such information shall be true, complete, and accurate.

WAIVERS AND AMENDMENTS: No waivers, amendments or modifications of this Note and
other Loan Documents shall be valid unless in writing and signed by an officer
of Bank. No waiver by Bank of any Default shall operate as a waiver of any other
Default or the same Default on a future occasion. Neither the failure nor the
delay on the part of Bank in exercising any right, power, or remedy under this
Note and other Loan Documents shall operate as a waiver thereof, nor shall a
single or partial exercise thereof preclude any other or further exercise
thereof or the exercise of any other right, power or remedy.

Each Borrower or any person liable under this Note waives presentment, protest,
notice of dishonor, demand for payment, notice of acceleration of maturity.
notice of sale and all other notices of any kind. Further, each agrees that Bank
may extend, modify or renew this Note or make a novation of the loan evidenced
by this Note for any period and grant any releases, compromise; or indulgences
with respect to any collateral securing this Note, or with respect to any other
Borrower or any other person liable under this Note or other Loan Documents, all
without notice to or consent of each Borrower or any person who may be liable
under this Note or other Loan Documents and without affecting the liability of
Borrower or any person who may be liable under this Note or Other Loan
Documents.

MISCELLANEOUS. This Note and other Loan Documents shall inure to the benefit of
and be binding upon the parties and their respective heirs, legal
representatives, successors and assigns. Bank's interests in and rights under
this Note and other Loan Documents we freely assignable, in whole or in part, by
Bank. In addition, nothing in this Note or any of the Loan Documents shall
prohibit Bank from pledging or assigning this Note or any of the Loan Documents
or any interest therein to any Federal Reserve Bank. Borrower shall not assign
its rights and interest hereunder without prior written consent of Bank, and any
attempt by Borrower to assign without Bank's prior written consent is null and
void. Any assignment shall not release Borrower from the Obligations.

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APPLICABLE LAW; CONFLICT BETWEEN DOCUMENTS. This Note and other Loan Documents
shall be governed by and construed under the laws of the state named in Bank's
address shown above without regard to that state's conflict of laws principles.
If the terms of this Note should conflict with the terms of the loan agreement
or any commitment letter and survives closing, the terms of this Note shall
control. BORROWER'S ACCOUNTS. Except as prohibited by law, Borrower grants Bank
a security interest in all of Borrower's accounts with Bank and any of its
affiliates. JURISDICTION. Borrower irrevocably agrees to non-exclusive personal
jurisdiction in the state named in Bank's address shown above. SEVERABILITY. If
any provision of this Note or of the other Loan Documents shall be prohibited or
invalid under applicable law, such provision shall be ineffective but only to
the extent of such prohibition or invalidity, without invalidating the remainder
of such provision or the remaining provisions of this Note or other such
document. NOTICES. Any notices to Borrower shall be sufficiently given, if in
writing and mailed or delivered to the Borrower's address shown above or such
other address as provided hereunder, and to Bank, if in writing and mailed or
delivered to Bank's office address shown above or such other address as Bank may
specify in writing from time to time. In the event that Borrower changes
Borrower's address at any time prior to the date the Obligations are paid in
full, Borrower agrees to promptly give written notice of said change of address
by registered or certified mail, return receipt requested, all charges prepaid.
PLURAL; CAPTIONS. All references in the Loan Documents to Borrower, guarantor,
person, document or other noun reference mean both he singular and plural form,
as the case may be, and the term "person" shall mean any individual, person or
entity. The captions contained in the Loan Documents are inserted for reference
only and shall not affect the meaning or interpretation of me Loan Documents.
BINDING CONTRACT. Borrower by execution of and Bank by acceptance of this Note
agree that each party is bound to all terms and provisions of this Note.
ADVANCES. Bank in its sole discretion may make other Advances under this Note
pursuant hereto. POSTING OF PAYMENTS. All payments received during normal
banking hours after 2:00 p.m. local time at the office of Bank first shown above
shall be deemed received at the opening of the next banking day. JOINT AND
SEVERAL OBLIGATIONS. Each Borrower is jointly and severally obligated under this
Note. FEES AND TAXES. Borrower shall promptly pay all documentary, intangible
recordation and/or similar taxes on this transaction whether assessed at closing
or arising from time to time.

ARBITRATION. Upon demand of any party hereto, whether made before or after
institution or any judicial proceeding, any dispute, claim or controversy
arising out of, connected with or relating to this Note and other Loan Documents
("Dispute") between or among parties to this Note shall be resolved by binding
arbitration as provided herein. Institution of a judicial proceeding by a party
does not waive the right of that party to demand arbitration hereunder. Disputes
may include, without limitation, tort claims, counterclaims, disputes as to
whether a matter is subject to arbitration, claims brought as class actions,
claims arising from Loan Documents executed in the future, or claims arising a
out of or connected with the transaction reflected by this Note.

Arbitration shall be conducted under and governed by the Commercial Financial
Disputes Arbitration Rules (the 'Arbitration Rules') of the American Arbitration
Association (the 'AAA') and Title 9 of the U.S. Code. All arbitration hearings
shall be conducted in the city in which the office of Bank first stated above is
located. The expedited procedures set forth in Rule 51 et seq.. of the
Arbitration Rules shall be applicable to claims of less than $1,000,000.00. All
applicable statutes of limitation shall apply to any Dispute. A judgment upon
the award may be entered in any court having jurisdiction. The panel from which
all arbitrators are selected shall be comprised of licensed attorneys. The
single arbitrator selected for expedited procedure shall be a retired judge from
the highest court of general jurisdiction state or federal, of the state where
the hearing will be conducted or if such person is not available to serve, the
single arbitrator may be a licensed attorney. Notwithstanding the foregoing, the
arbitration provision does not apply to disputes under or related to swap
agreements.

PRESERVATION AND LIMITATION OF REMEDIES. Notwithstanding the preceding binding
arbitration provisions, Bank and Borrower agree to preserve, without limitation,
certain remedies that any party hereto may employ or exercise freely,
independently or in connection with an arbitration proceeding or after an
arbitration action is brought. Bank and Borrower shall have the right to proceed
in any court of proper jurisdiction or by self-help to exercise or prosecute the
following remedies, as applicable: (i) all rights to foreclose, against any real
or personal property or other security by exercising a power of sale Under Loan
Documents or under applicable law or by judicial foreclosure and sale, including
proceeding to confirm the sale; (ii) all rights of self-help including 
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peaceful occupation of real property and collection of rents, set-off, and
peaceful possession of personal property; (iii) obtaining provisional or
ancillary remedies including injunctive relief, sequestration, garnishment,
attachment, appointment, of receiver and filing an involuntary bankruptcy
proceeding; and (iv) when applicable a judgment by confession of judgment.
Preservation of these remedies does not limit the power of an arbitrator to
grant similar remedies that may be requested by a party in Dispute.

Borrower and Bank agree that they shall not have a remedy of punitive or
exemplary damages against the other in any Dispute and1 hereby waive any right
or claim to punitive or exemplary damages they have now or which may arise in
the future in connection with any Dispute whether the Dispute is resolved by
arbitration or judicially.

IN WITNESS WHEREOF, the undersigned have signed and sealed this Note the day and
year first above written.

                                    Kyzen Corporation
                                    Taxpayer Identification Number 87-0475115

CORPORATE                           By: /s/ Benjamin D. Wolfley
SEAL                                    -----------------------------------
                                        Benjamin D. Wolfley, Treasurer