EXHIBIT 10.21 RWG Inc. 6601 Windy Hill Way Reno, NV 89511 ENGAGEMENT AGREEMENT This Agreement, dated July 1, 2004, between SulphCo, Inc. a Nevada Corporation and RWG Inc., a Nevada Corporation, is to set forth the conditions for the engagement of the services of Dr. Rudolf W. Gunnerman, President and CEO of RWG Inc. to SulphCo, Inc. and its shareholders. Description of Services: Dr. Gunnerman will be responsible for the functions of the Chief Executive Officer and Chairman of the Board. Service Fees: SulphCo, Inc. will pay a yearly fee of $480,000.00. Agreement Term: This Agreement will terminate after one year, on July 1, 2005. /s/ Kirk S. Schumacher - ----------------------- Kirk S. Schumacher President, SulphCo, Inc. /s/ Rudolf W. Gunnerman - ----------------------- Rudolf W. Gunnerman President and CEO, RWG Inc.