Use of Natural Zeolites in Agronomy, Horticulture and Environmental Soil Remediation

Abstract

“In the next century, it is possible that a huge industry will develop based on natural zeolites. Soil conditioning by zeolites might lead to greater agricultural production. Control of toxic materials in waste water by zeolites might rescue some stressed aquasystems. There just might be gold for geochemists in them thar zeolite beds.” J. V. Smith (1988) The use of natural zeolites to improve plant productivity or as a remediation agent in environmental protection has the potential of becoming a “huge” industry as pointed out in the above quote by Smith (1988). This potential industry is based on the unique chemical and physical properties of natural zeolites (e.g. high cation-exchange capacities, cation selectivity, molecular sieving) and their widespread occurrence in sedimentary deposits derived from volcanic materials. A variety of potential applications have been examined for natural zeolites, including use as soil conditioners, slow-release fertilizers, soilless substrates, carriers for insecticides and pesticides, and remediation agents in contaminated soils. However, although numerous applications have been suggested or examined, today there are only a few commercial markets for natural zeolites in the horticultural, agronomic, and environmental protection industries. Allen and Ming (1995) suggested that there may be several reasons that the commercial use of natural zeolites has been slow to develop, including (1) the lack of studies that focus on deriving the economic benefits of zeolite applications; (2) the need to develop products and formulations that meet a specific agronomic, horticultural, or environmental use, instead of a one-size-fits-all approach; (3) the need to fully characterize the zeolite or zeolite-containing material before it is utilized; and (4) the lack of sound scientific research to support the proposed uses of zeolites. We agree with J.V. Smith that the potential applications for natural zeolites are huge, provided the proper research is conducted to fully use …