
<PAGE>

                                                                      EXHIBIT 25
 
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

                          ___________________________

                                    FORM T-1

                            STATEMENT OF ELIGIBILITY
                   UNDER THE TRUST INDENTURE ACT OF 1939 OF A
                    CORPORATION DESIGNATED TO ACT AS TRUSTEE

         Check if an application to determine eligibility of a Trustee
                      pursuant to Section 305 (b)(2) ____

                            ________________________

                                 CITIBANK, N.A.
              (Exact name of trustee as specified in its charter)

                                                  13-5266470         
                                                  (I.R.S. employer   
                                                  identification no.) 

399 Park Avenue, New York, New York               10043
(Address of principal executive office)           (Zip Code)

                            _______________________

                                  Ashland Inc.
              (Exact name of obligor as specified in its charter)

Kentucky                                          61-0122250
(State or other jurisdiction of                   (I.R.S. employer
incorporation or organization)                    identification no.)

 
1000 Ashland Drive
Russell, Kentucky                                 41169
(Address of principal executive offices)          (Zip Code)

                           _________________________

                                Debt Securities
                      (Title of the indenture securities)
<PAGE>
 
Item 1.   General Information.

          Furnish the following information as to the trustee:

     (a)  Name and address of each examining or supervising authority to which
          it is subject.

          Name                                            Address
          ----                                            -------
          Comptroller of the Currency                 Washington, D.C.

          Federal Reserve Bank of New York            New York, NY
          33 Liberty Street
          New York, NY

          Federal Deposit Insurance Corporation       Washington, D.C.

     (b)  Whether it is authorized to exercise corporate trust powers.

          Yes.

Item 2.   Affiliations with Obligor.

          If the obligor is an affiliate of the trustee, describe each such
          affiliation.

          None.

Item 16.  List of Exhibits.

          List below all exhibits filed as a part of this Statement of
          Eligibility.

          Exhibits identified in parentheses below, on file with the Commission,
          are incorporated herein by reference as exhibits hereto.

          Exhibit 1 - Copy of Articles of Association of the Trustee, as now in
          effect.  (Exhibit 1 to T-1 to Registration Statement No. 2-79983)

          Exhibit 2 - Copy of certificate of authority of the Trustee to
          commence business. (Exhibit 2 to T-1 to Registration Statement No. 2-
          29577).

          Exhibit 3 - Copy of authorization of the Trustee to exercise corporate
          trust powers.  (Exhibit 3 to T-1 to Registration Statement No. 2-
          55519)

          Exhibit 4 - Copy of existing By-Laws of the Trustee. (Exhibit 4 to T-1
          to Registration Statement No. 33-34988)

          Exhibit 5 - Not applicable.
<PAGE>
 
          Exhibit 6 - The consent of the Trustee required by Section 321(b) of
          the Trust Indenture Act of 1939. (Exhibit 6 to T-1 to Registration
          Statement No. 33-19227.)

          Exhibit 7 - Copy of the latest Report of Condition of Citibank, N.A.
          (as of December 31, 1997 - attached)

          Exhibit 8 -  Not applicable.

          Exhibit 9 -  Not applicable.

                               __________________


                                   SIGNATURE

     Pursuant to the requirements of the Trust Indenture Act of 1939, the
Trustee, Citibank, N.A., a national banking association organized and existing
under the laws of the United States of America, has duly caused this statement
of eligibility to be signed on its behalf by the undersigned, thereunto duly
authorized, all in The City of New York and State of New York, on the 19th day
of March, 1998.



                                                CITIBANK, N.A.


                                                By  /s/Carol Ng
                                                    ----------------------
                                                    Carol Ng
                                                    Vice President
<PAGE>
 
                               Charter No. 1461
                          Comptroller of the Currency
                             Northeastern District
                              REPORT OF CONDITION
                                 CONSOLIDATING
                             DOMESTIC AND FOREIGN
                                SUBSIDIARIES OF

                                Citibank, N.A.

of New York in the State of New York, at the close of business on December 31,
1997, published in response to call made by Comptroller of the Currency, under
Title 12, United States Code, Section 161. Charter Number 1461 Comptroller of
the Currency Northeastern District.

                                    ASSETS
                                                                 Thousands  
                                                                 of dollars 
Cash and balances due from de-
     pository institutions:
     Noninterest-bearing balances
     and currency and coin...................................   $  7,788,000
Interest-bearing balances....................................     14,245,000
Held-to-maturity securities..................................              0
Available-for-sale securities................................     28,951,000
     Federal funds sold and
       securities purchased under
       agreements to resell..................................      9,776,000
Loans and lease financing receiv-
     ables:
     Loans and Leases, net of un-
     earned income...........................  $153,670,000
     LESS: Allowance for loan
     and lease losses........................     4,264,000
Loans and leases, net of un-
     earned income, allowance,
     and reserve.............................................    149,406,000
Trading assets...............................................     36,106,000
Premises and fixed assets (includ-
     ing capitalized leases).................................      3,338,000
Other real estate owned......................................        609,000
Investments in unconsolidated
     subsidiaries and associated com-
     panies..................................................      1,320,000
Customers' liability to this bank
     on acceptances outstanding..............................      1,726,000
Intangible assets............................................        164,000
Other assets.................................................      9,071,000
                                                                ------------
TOTAL ASSETS.................................................   $262,500,000
                                                                ============

                                  LIABILITIES

Deposits:
     In domestic offices.....................................   $ 37,569,000
     Noninterest-
     bearing.................................................   $ 13,472,000
     Interest-
     bearing.................................................     24,097,000
In foreign offices, Edge and
     Agreement subsidiaries, and
     IBFs....................................................    141,000,000
     Noninterest-
     bearing.................................     9,460,000
     Interest-
     bearing.................................   131,540,000
Federal funds purchased and
     securities sold under agree-
     ments to repurchase.....................................      8,574,000
Trading liabilities..........................................     27,811,000
Other borrowed money (includes
mortgage indebtedness and
obligations under capitalized
leases):
     With a remaining maturity of one
     year or less............................................      8,647,000
     With a remaining maturity of more
     than one year through three years.......................      2,530,000
     With a remaining maturity of more
     than three years........................................        910,000
Bank's liability on acceptances ex-
     ecuted and outstanding..................................      1,826,000
Subordinated notes and
debentures...................................................      5,600,000
Other liabilities............................................     10,865,000
                                                                ------------
TOTAL LIABILITIES............................................   $245,332,000
                                                                ============

                                EQUITY CAPITAL

Perpetual preferred stock
     and related surplus.....................................              0
Common stock.................................................   $    751,000
Surplus......................................................      7,453,000
Undivided profits and capital re-
     serves..................................................      9,318,000
Net unrealized holding gains (losses)
     on available-for-sale securities........................        345,000
Cumulative foreign currency
     translation adjustments.................................       (699,000)
                                                                ------------
TOTAL EQUITY CAPITAL.........................................   $ 17,168,000
                                                                ============
TOTAL LIABILITIES, LIMITED-
     LIFE PREFERRED STOCK, AND
     EQUITY CAPITAL..........................................   $262,500,000
                                                                ============

I, Roger W. Trupin, Controller of the above-named bank do hereby declare that
this Report of Condition is true and correct to the best of my knowledge and
belief.
                                                ROGER W. TRUPIN
                                                CONTROLLER

We, the undersigned directors, attest to the correctness of this Report of
Condition. We declare that it has been examined by us, and to the best of our
knowledge and belief has been prepared in conformance with the instructions and
is true and correct.
                                                PAUL J. COLLINS  
                                                JOHN S. REED     
                                                WILLIAM R. RHODES
                                                DIRECTORS         
