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                                  Exhibit 10.7

                          STOCK SUBSCRIPTION AGREEMENT

         This Stock Subscription Agreement is entered into as of January 13
2003, by SulphCo, Inc., a Nevada corporation (the "Corporation") and Kirk S.
Schumacher (the "Purchaser").

SECTION 1. Acquisition of Shares.

         (a) SALE AND PURCHASE. On the terms and conditions set forth in this
Agreement, the Corporation agrees to sell to the Purchaser, and the Purchaser
agrees to purchase from the Corporation, Fifty Thousand (50,000) shares of the
Common Stock of the Corporation (the "Shares"). The sale and purchase of the
Shares is made pursuant to the exercise of an option granted on December 23,
2002, to acquite shares of the Corporation's common stock at the ten then
current market price of shares of the Common Stock of the Corporation, being
thirty-three cents ($.33) per share. The closing shall occur at the offices of
the Corporation on the date set forth above or at such other place and time as
the parties may agree.

         (b) CONSIDERATION. The Purchaser agrees to pay Thirty-Three Cents
($.33) for the Shares, for a total of Sixteen Thousand Five Hundred Dollars
($16,500.00).

         (c) DEFINED TERMS. Capitalized terms not defined above are defined in
Section 9 of this Agreement.

SECTION 2. Restrictions.

          (a) PURCHASER REPRESENTATIONS. In connection with the issuance and
acquisition of Shares under this Agreement, the Purchaser hereby represents and
warrants to the Corporation as follows:

                  (i) The Purchaser is acquiring and will hold the Shares for
investment for his or her account only and not with a view to, or for resale in
connection with, any "distribution" thereof within the meaning of the Securities
Act.

                  (ii) The Purchaser understands that the Shares have not been
registered under the Securities Act by reason of a specific exemption therefrom
and that the Shares must be held indefinitely, unless they are subsequently
registered under the Securities Act or the Purchaser obtains an opinion of
counsel, in form and substance satisfactory to the Corporation and its counsel,
that such registration is not required. The Purchaser further acknowledges and
understands that the Corporation is under no obligation to register the Shares.

                  (iii) The Purchaser is aware of the adoption of Rule 144 by
the Securities and Exchange Commission under the Securities Act, which permits
limited public resales of securities acquired in a non-public offering, subject
to the satisfaction of certain conditions, including (without limitation) the
availability of certain current public information about the issuer, the resale
occurring only after the holding period required by Rule 144 has been satisfied,
the sale occurring through an unsolicited "broker's transaction," and the amount
of securities being sold during any three-month period not exceeding specified
limitations.

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                  (iv) The Purchaser will not sell, transfer or otherwise
dispose of the Shares in violation of the Securities Act, the Securities
Exchange Act of 1934, or the rules promulgated thereunder, including Rule 144
under the Securities Act. The Purchaser agrees that he or she will not dispose
of the Shares unless and until he or she has complied with all requirements of
this Agreement applicable to the disposition of Shares and he or she has
provided the Corporation with written assurances, in substance and form
satisfactory to the Corporation, that (A) the proposed disposition does not
require registration of the Shares under the Securities Act or all appropriate
action necessary for compliance with the registration requirements of the
Securities Act or with any exemption from registration available under the
Securities Act (including Rule 144) has been taken and (B) the proposed
disposition will not result in the contravention of any transfer restrictions
applicable to the Shares under any "blue sky" laws.

                  (v) The Purchaser has been furnished with, and has had access
to, such information as he or she considers necessary or appropriate for
deciding whether to invest in the Shares, and the Purchaser has had an
opportunity to ask questions and receive answers from the Corporation regarding
the terms and conditions of the issuance of the Shares.

                  (vi) The Purchaser is aware that his or her investment in the
Corporation is a speculative investment that has limited liquidity and is
subject to the risk of complete loss. The Purchaser is able, without impairing
his or her financial condition, to hold the Shares for an indefinite period and
to suffer a complete loss of his or her investment in the Shares.

         (b) SECURITIES LAW RESTRICTIONS. Regardless of whether the offering and
sale of Shares under this Agreement have been registered under the Securities
Act or have been registered or qualified under the securities laws of any state,
the Corporation at its discretion may impose restrictions upon the sale, pledge
or other transfer of the Shares (including the placement of appropriate legends
on stock certificates or the imposition of stop-transfer instructions) if, in
the judgment of the Corporation, such restrictions are necessary or desirable in
order to achieve compliance with the Securities Act, the securities laws of any
state or any other law.

         (c) RIGHTS OF THE CORPORATION. The Corporation shall not be required to
(i) transfer on its books any Shares that have been sold or transferred in
contravention of this Agreement or (ii) treat as the owner of Shares, or
otherwise to accord voting, dividend or liquidation rights to, any transferee to
whom Shares have been transferred in contravention of this Agreement.

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SECTION 3. Successors and Assigns.

         Except as otherwise expressly provided to the contrary, the provisions
of this Agreement shall inure to the benefit of, and be binding upon, the
Corporation and its successors and assigns and be binding upon the Purchaser and
the Purchaser's legal representatives, heirs, legatees, distributees, assigns
and transferees by operation of law, whether or not any such person has become a
party to this Agreement or has agreed in writing to join herein and to be bound
by the terms, conditions and restrictions hereof.

SECTION 4.  No Retention Rights.

         Nothing in this Agreement shall confer upon the Purchaser any right to
continue as the corporation's counsel for any period of specific duration or
interfere with or otherwise restrict in any way the rights of the Corporation or
the Purchaser, which rights are hereby expressly reserved by each, to terminate
his or her service at any time and for any reason, with or without cause.

SECTION 5. Legend.

         All certificates evidencing Purchased Shares shall bear substantially
the following legend:

"THE SHARES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR OTHERWISE TRANSFERRED
WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT OR AN OPINION OF
COUNSEL, SATISFACTORY TO THE COMPANY AND ITS COUNSEL, THAT SUCH REGISTRATION IS
NOT REQUIRED."

         If required by the authorities of any state in connection with the
issuance of the Purchased Shares, the legend or legends required by such state
authorities shall also be endorsed on all such certificates.

SECTION 6. Notices.

         Any notice required by the terms of this Agreement shall be given in
writing and shall be deemed effective upon personal delivery or upon deposit
with the United States Postal Service, by registered or certified mail, with
postage and fees prepaid. Notice shall be addressed to the Corporation at its
principal executive office and to the Purchaser at the address that he or she
most recently provided to the Corporation.

SECTION 7. Entire Agreement.

         This Agreement constitutes the entire contract between the parties
hereto with regard to the subject matter hereof. It supersedes any other
agreements, representations or understandings (whether oral or written and
whether express or implied) relating to the subject matter hereof.

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SECTION 8. Choice of Law.

         This Agreement shall be governed by, and construed in accordance with,
the laws of the State of Nevada, as such laws are applied to contracts entered
into and performed in such State.

SECTION 9. Definitions.

         (a) "Agreement" shall mean this Stock Purchase Agreement.

         (b) "Board of Directors" shall mean the Board of Directors of the
Corporation, as constituted from time to time.

         (c) "Corporation" shall mean SulphCo, Inc., a Nevada corporation.

         (d) "Shares" shall mean the Shares purchased by the Purchaser pursuant
to this Agreement.

         (e) "Purchase Price" shall mean the amount for which one Share may be
purchased pursuant to this Agreement, as specified in Section 1(b).

         (f) "Securities Act" shall mean the Securities Act of 1933, as amended.

         (g) "Share" shall mean one share of Stock.

         IN WITNESS WHEREOF, the Corporation and the Purchaser have executed
this Agreement to be effective as of January 13, 2003.

CORPOPORATION:                              SULPHCO, INC.

                                            By  /s/ Rudolf W. Gunnerman
                                                ------------------------
                                                Name:  Rudolf Gunnerman
                                                Title:  CEO

PURCHASER:                                  /S/ KIRK S. SCHUMACHER
                                            ----------------------
                                            Kirk S. Schumacher

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                                  EXHIBIT 10.8

                                 PROMISSORY NOTE

Principal Amount: $1,920,000                     Date of Note: February 28, 2003
Interest Rate:  7.5%

         FOR VALUE RECEIVED, the undersigned, SulphCo, Inc., a Nevada
corporation ("Borrower"), promises to pay in lawful money of the United States
of America to the order of Rudolf W. Gunnerman ("Lender"), at such place as
Lender may designate in writing from time to time, the principal sum of One
Million Nine Hundred Twenty Thousand and No/100 Dollars ($1,920, 000), with
interest from February 28, 2003 on the unpaid principal balance at the rate set
forth below.

1. INTEREST. Interest shall accrue on the unpaid principal balance at a rate
from February 28, 2003, to the Maturity Date at Seven and One-Half Percent
(7.5%) per annum. Interest shall be computed on the basis of a 365-day year (or
a 366-day year during a leap year) and actual days elapsed.

2. PAYMENTS AND TERM. The entire indebtedness of principal and interest
evidenced by this Note, if not sooner paid, shall be due and payable in a single
payment on February 28, 2004 (the "Maturity Date"). All payments on account of
the indebtedness evidenced by this Note shall be first applied to interest and
costs owed under this Note (if any) and then to principal.

3. PREPAYMENT. The indebtedness evidenced by this Note may be prepaid, in whole
or in part, with or without interest, and without payment of a prepayment fee.

4. DEFAULT. The occurrence of any one or more of the following shall constitute
an event of default under this Note:

         (i)      Failure to make any payment of principal or interest when due;
                  or
         (ii)     The occurrence of any other event of any other event of
                  default under this Note following ten (10) days written notice
                  thereof to the Borrower.

         Time is of the essence. If an event of default occurs under this Note
after the passage of applicable cure periods, (i) the entire principal balance
hereof and all accrued interest shall, at the option of Lender, without notice,
bear interest at a rate from time to time equal to five (5) percentage points
over what would otherwise be the Note rate (or the maximum rate permitted by
applicable law if that is less) from the date of the event of default until such
event of default is cured and (ii) the entire principal balance hereof and all
accrued interest shall immediately become due and payable at the option of
Lender, without notice. Lender's failure to exercise any option hereunder shall
not constitute a waiver of the right to exercise the same for any subsequent
event of default.

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5. COSTS AND ATTORNEYS' FEES. If an event of default occurs under this Note and
Lender consults an attorney regarding the enforcement of any of its rights under
this Note, or if this Note is placed in the hands of an attorney for collection,
or if suit be brought to enforce this Note, Borrower promises to pay all costs
thereof, including attorneys' fees. Said costs and attorneys' fees shall
include, without limitation, costs and attorneys' fees in any appeal or in a
proceeding under any present or future federal bankruptcy act or state
receivership.

6. SECURITY. This Note is unsecured.

7. WAIVER OF PRESENTMENT, ETC. Borrower hereby waives presentment and demand for
payment, notice of dishonor, protest and notice of protest.

8. GOVERNING LAW. This Note shall be construed, enforced and otherwise governed
by the laws of the State of Nevada.

Dated as of the 28th day of February, 2003.

SULPHCO, INC.

By:  /S/ RUDOLF W. GUNNERMAN
     -----------------------
         Dr. Rudolf W. Gunnerman
         Chairman & CEO

By:  /S/ KIRK S. SCHUMACHER
     ----------------------
         Kirk S. Schumacher
         President

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