2001 Progress Report: Zeolite Coatings by In-Situ Crystallization as an Environmentally Benign Alternative to Chromate Conversion and Anodization Coatings

EPA Grant Number: R828134
Title: Zeolite Coatings by In-Situ Crystallization as an Environmentally Benign Alternative to Chromate Conversion and Anodization Coatings
Investigators: Yan, Yushan
Institution: University of California - Riverside
EPA Project Officer: Richards, April
Project Period: August 1, 2000 through July 31, 2003 (Extended to July 31, 2004)
Project Period Covered by this Report: August 1, 2000 through July 31, 2001
Project Amount: $250,316
RFA: Technology for a Sustainable Environment (1999) RFA Text |  Recipients Lists
Research Category: Nanotechnology , Sustainability , Pollution Prevention/Sustainable Development


The objective of this proposed project is to develop a chromium-free zeolite coating that has comparable thickness to chromate conversion and anodization coatings and equivalent or superior performance in coating adhesion, corrosion protection, abrasion resistance, and paint adhesion. An intrinsically inexpensive, safe, and nonpolluting in-situ crystallization process that is capable of coating large surfaces with complex shapes and in confined spaces also will be developed. Zeolites are microporous crystalline silicate materials and have widely been exploited for their microporosity (< 15?) as catalysts and separation media. However, many high silica zeolites are nonporous in their as-synthesized state because of the organic molecules occluded in their pores during crystallization. High silica zeolites also are known for their thermal and chemical stability and high mechanical strength. The goal of this project is to explore these dense polycrystalline high silica or pure silica zeolite films in their as-synthesized state for corrosion protection.

Progress Summary:

We have demonstrated that high silica zeolite ZSM-5 coatings on aluminum alloys and steel are extremely corrosion resistant in strong acids, bases, and pitting aggressive environments. We also have demonstrated that the in-situ crystallization coating deposition method we developed is capable of coating surfaces of complex shapes and in confined spaces?two key features of an anodization process. Also, we have demonstrated that the ZSM-5 coating has good adhesion and thermal and thermal shock stability and performs reasonably well under bending and mechanical impact. It also can be easily painted with widely used polymeric paints.

Future Activities:

We are extending this technology to other zeolites such as MTW, BEA, LTA, and MFI with different composition to study if the approach is general for all zeolites. Also, we are investigating to shorten the deposition time and lower the reaction pressure.

Journal Articles on this Report : 1 Displayed | Download in RIS Format

Other project views: All 36 publications 19 publications in selected types All 18 journal articles
Type Citation Project Document Sources
Journal Article Cheng X, Wang Z, Yan Y. Corrosion-resistant zeolite coatings by in situ crystallization. Electrochemical and Solid-State Letters 2001;4(5):B23-B26. R828134 (2001)
R828134 (2002)
R828134 (2003)
R828134 (Final)
  • Abstract: ECS - Abstract
  • Supplemental Keywords:

    corrosion, zeolite, coating, film, thin film, aluminum, aluminum alloys, steel, chromium, anodization, conversion coating., RFA, Scientific Discipline, Toxics, Water, Sustainable Industry/Business, cleaner production/pollution prevention, Wastewater, Environmental Chemistry, Sustainable Environment, Technology for Sustainable Environment, 33/50, Environmental Engineering, hexavalent chromium, in situ crystallization, environmentally conscious manufacturing, chromium & chromium compounds, cleaner production, zeolites, environmentally benign solvents, alternative materials, anodization coatings, metal plating industry, carcinogenicity, coating processes, innovative technology, microelectronics, water treatment, corrsion protection, pollution prevention, chromium free surface finishing

    Relevant Websites:

    http://www.engr.ucr.edu/~yushan Exit EPA icon

    Progress and Final Reports:

    Original Abstract
    2002 Progress Report
    2003 Progress Report
    Final Report