Clean Diesel Technologies Reports Test Results Show Potential for Immediate Reductions in Particulate and NOx Emissions From Its New Cleaner Burning Diesel Fuel.

Business Editors

STAMFORD, Conn.--(BUSINESS WIRE)--May 25, 2000

Teams With RAD Energy Corp to Develop New Low Emissions Fuel

Clean Diesel Technologies, Inc. (EBB:CDTI) (CDT) Thursday announced that results of initial engine testing at San Antonio-based Southwest Research Institute (SwRI) demonstrated that the company's new Cleaner Burning Diesel(TM) fuel, a formulation incorporating its Platinum Plus(R) bimetallic fuel borne catalyst (FBC), reduced particulate matter (PM) by 33 percent and NOx emissions by 10 percent compared with a commercial No. 2 diesel fuel.

The tests, which were done on a 1998 DDC Series 60 400hp engine, also compared CDT's Cleaner Burning Diesel fuel to a low sulfur "market blend" of CARB certified diesel. Cleaner Burning Diesel fuel is currently undergoing commercial field evaluation and additional engine tests, as well, and CDT has filed for a patent on this new fuel blend.

The company's Cleaner Burning Diesel fuel is being developed in conjunction with Purchase, NY-based RAD Energy Corp, a major provider of motor fuel and fleet management services to fleets and governmental agencies, and a leading innovator in delivering cleaner diesel technologies. Steven J. Levy, vice president of RAD Energy said, "We are very excited about these test results and look forward to bringing this product to market."

CDT Chief Executive Officer Jeremy D. Peter-Hoblyn commented, "Since all the components of the fuel are already registered with the EPA for use in bulk fuels, we don't anticipate any delays. We already have a fleet of 40 vehicles running on the fuel in a field evaluation and we expect to submit data for 'verification' of the emissions benefits under the EPA's voluntary retrofit/rebuild program."

CDT reports that its new Cleaner Burning Diesel fuel is based on a high-quality pipeline grade of jet/kero diesel fuel plus an additive package containing a lubricity agent, detergent and the company's bimetallic platinum/cerium FBC. CDT estimates the cost of the additive package will be in the range of 5 to 6 cents per gallon of fuel treated in addition to the incremental cost of pipeline quality jet/kero. Engine test work, however, measured no fuel economy penalty or loss of power for the new fuel blend.

According to CDT, an important commercial benefit of its Cleaner Burning Diesel is that jet/kero diesel fuel and the additive package are available nationwide so emissions benefits could be immediate for those areas looking to reduce NOx and PM from existing diesel engines. If field trials and additional engine testing confirm these data, CDT expects to make Cleaner Burning Diesel fuel available through a network of licensed regional fuel distributors who will be responsible for assuring that the final fuel/additive blend is to CDT's specifications.

CDT also intends to explore the use of its Cleaner Burning Diesel fuel in conjunction with engine timing changes and its LOE-NOx(TM) water-in-oil emulsion technology to maximize NOx reduction. They will also look at the performance of various particulate filters and oxidation catalysts with the fuel for ultra-low PM levels.

Engine Test Results:

Based on composite transient tests over the FTP test cycle, the new Cleaner Burning Diesel fuel reduced PM by 33 percent and NOx by 10 percent below baseline emission levels measured on straight No. 2 diesel fuel. Compared with certification levels for the engine of 0.1g/bhp-hr for PM and 4.0g/bhp-hr for NOx, PM was reduced by 50 percent to 0.05g/bhp-hr and NOx to 3.66g/bhp-hr.

Comparison of PM/NOx Emissions for CDT's Cleaner Burning
Diesel Fuel versus No. 2 Diesel and CARB Market Blend

                                              PM               NOx
                                             (g/bhp-hr)
Baseline No. 2D (350ppmS)                     0.075             4.05
Baseline CARB "Market Blend" (50ppmS)         0.063             3.72
Cleaner Burning Diesel with Platinum
Plus FBC                                      0.050             3.66

When used with the baseline No. 2 diesel or CARB "market blend" diesel fuel, the bimetallic FBC also produced PM reductions of 13 to 16 percent with no change in NOx.

About Clean Diesel Technologies, Inc:

Clean Diesel Technologies, Inc. is a specialty chemical company with patented products that reduce emissions from diesel engines while simultaneously improving fuel economy and power. Products include Platinum Plus fuel catalysts and the ARIS(TM) 2000 urea injection systems for selective catalytic reduction of NOx. Platinum Plus is a registered trademark of Clean Diesel Technologies, Inc.

Certain statements in this news release constitute "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements involve known or unknown risks, including those detailed in the company's filings with the Securities and Exchange Commission, uncertainties and other factors which may cause the actual results, performance or achievements of the company, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof.