(CDTI) Reports Compelling Vehicle Test Results for Spinel(TM) Technology

Tests on Two Car Models Show Spinel(TM) Eliminating Over 90% of PGMs on Underfloor Catalysts

OXNARD, Calif., June 2, 2015  — Clean Diesel Technologies, Inc. (Nasdaq:CDTI) (“CDTi” or “the Company”), a leader in advanced emission control technology, announced initial vehicle test results for Spinel™, its proprietary clean emissions exhaust technology that is expected to dramatically reduce the cost for auto manufacturers to attain increasingly stringent clean air standards.

Initial vehicle tests were conducted at an independent test facility using the industry standard Federal Test Procedure (FTP) on a model year 2014 Buick Regal 2.0 liter turbo-charged gasoline direct injection (GDI) engine. The data demonstrated that a Spinel underfloor catalyst with 97% less platinum group metal (PGM) achieved emissions control performance equivalent to the OEM catalyst. The Spinel catalyst PGM loading was 2g/ft3 compared to 59g/ft3 for the OEM catalyst. The Spinel catalyst at 2g/ft3 also provided equivalent performance to the OEM catalyst at 22g/ft3 on a 2014 Toyota Camry with a 2.5 liter naturally-aspirated engine – a PGM savings of 91%. For many passenger cars, these levels of PGM reduction could translate into double-digit dollar cost savings per vehicle, reinforcing Spinel’s strong value proposition for OEMs.

“These encouraging initial results from rigorous FTP testing demonstrate the significant potential of our Spinel technology,” stated Chris Harris, CDTi’s President and CEO. “Spinel could provide OEMs with a cost-effective solution as they face the prospect of increased PGM usage while phasing in next-generation fuel-efficient engines that must meet tighter emission regulations. Passenger cars typically have two catalysts for different exhaust zones, and our program was designed to develop and test proprietary Spinel systems for the underfloor position first and then move on to testing the close-coupled catalyst. These initial results suggest we now have an ultra-low PGM option for underfloor catalysts. In addition, analysis of the post-test catalysts have provided insights into further improvements, reinforcing the possibility that Spinel eventually might be able to eliminate PGMs altogether. We continue with validation testing on close-coupled catalysts, and we expect to report those results later this year.

“We are excited about recent results for Spinel and our other next-generation technologies – BMARS™ and SPGM™ DOC. These technologies could enable the light and heavy duty vehicle industries to reduce the billions of dollars currently spent on PGMs, as well as address the increasing risks of supply constraints and price volatility surrounding strategic materials like PGMs and rare earths,” Harris concluded.

Benchmark Testing Results

The chart below summarizes the results of the initial vehicle testing conducted on the 2014 Buick Regal at an independent test facility using the industry standard FTP. Results show the oxides of nitrogen (NOx) emission of the OEM system, consisting of a close-coupled catalyst and an underfloor catalyst, compared to the OEM close-coupled catalyst with CDTi’s Spinel underfloor catalyst. The PGM cost reflects that of the underfloor catalyst only, with the PGM price calculated as of May 1, 2015.

A chart accompanying this release is available at http://media.globenewswire.com/cache/9503/file/34558.jpg

About Spinel

The Spinel™ platform is a family of proprietary materials using various base metals that replace costly platinum group metals (PGMs) and rare earth metals in coatings on standard catalytic converters. Spinel is expected to work across a wide range of engine and vehicle applications – both gasoline and diesel – and has the potential for significant cost savings for OEMs by dramatically reducing or eliminating expensive PGMs and rare earth metals. The technology could enable early, cost-effective compliance with stricter emissions standards in the U.S. and around the world, while mitigating OEM exposure to supply uncertainty and price volatility in the PGM and rare earth markets. More information may be obtained at www.cdti.com/spinel.

About CDTi

CDTi manufactures and distributes vehicle emissions control products that leverage its advanced materials technology. CDTi utilizes its proprietary patented Mixed Phase Catalyst (MPC®) technology and other related technologies to provide high-value sustainable solutions to reduce emissions, increase energy efficiency and lower the carbon intensity of on- and off-road combustion engine systems. Reflecting its continued focus on innovation, CDTi is developing and commercializing proprietary advanced low-platinum group metal (PGM) catalysts including synergized-PGM (SPGM™), as well as zero-PGM (ZPGM™) catalysts. CDTi is headquartered in Oxnard, California and has operations in the U.K., Canada, France, Japan and Sweden. For more information, please visit www.cdti.com.

Forward-Looking Statements

Certain information contained in this press release constitutes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including any statements that are not statements of historical fact. You can identify these forward-looking statements by the use of the words “believes”, “expects”, “anticipates”, “plans”, “may”, “will”, “would”, “intends”, “estimates”, “promises”, and other similar expressions, whether in the negative or affirmative. Forward-looking statements are based on a series of expectations, assumptions, estimates and projections which involve substantial uncertainty and risk. In this press release, the Company includes forward looking statements regarding the potential benefits of CDTi’s Spinel technology based on recent test results, and the anticipated further testing, development, potential applications, commercialization opportunities and potential benefits of CDTi’s catalyst technologies including Spinel. In general, actual results may differ materially from those indicated by such forward-looking statements as a result of risks and uncertainties, including, but not limited, to (i) Spinel technology may not achieve results with close-coupled catalysts similar to the results for underfloor catalysts; and, moreover, products or technologies such as Spinel may not achieve the same results in commercial environments as they do in test settings; (ii) that the Company may not be able to (a) decrease costs, (b) increase sales, (c) obtain adequate funding, (d) retain existing or secure new customers (e) protect its intellectual property, (f) successfully evolve into an advanced materials supplier or, even if successful, achieve profitability, (g) successfully market new products; (h) obtain required product verification or approvals, (i) attract or retain key personnel, or (j) realize benefits from investments; (iii) prices of PGM and rare earth metals; (iv) supply disruptions or failures; (v) regulatory, marketing and competitive factors; (vi) environmental harm or damages, (vii) changes in domestic and international market and political conditions; and (viii) other risks and uncertainties discussed or referenced in the Company’s filings with the Securities and Exchange Commission, including its most recent Annual Report on Form 10-K. In addition, any forward-looking statements represent the Company’s estimates only as of the date of such statements and should not be relied upon as representing the Company’s estimates as of any subsequent date. The Company specifically disclaims any obligation to update forward-looking statements. All forward-looking statements in this press release are qualified in their entirety by this cautionary statement.

CONTACT: Becky Herrick or Cathy Mattison
         LHA (IR Agency)
         +1 415 433 3777
         bherrick@lhai.com
         cmattison@lhai.com