Recovery of sodium sulfate from farm drainage salt for use in reactive dyeing of cotton.
Agricultural drainage salt generated during irrigation of crops in San Joaquin Valley, California, exceeds 600,000 tons annually and cumulates in the field at a rapid rate. As a result, the waste is occupying more farmland for salt storage and disposal, thus causing serious concern to the environment and the local agricultural industry. In searching for a potential solution to reduce or eliminate the waste, the research describe herein explored the feasibility of producing a value-added product, sodium sulfate, from the waste and utilizing the product in textile dyeing. The results indicated that sodium sulfate could be produced from the salt and could be purified by a recrystalization method in a temperature range within the highest and lowest daily temperatures during summer in the valley. The recovered sodium sulfate samples, with purities ranging from 67 to 99.91%, were compared with commercially available sodium sulfate used in reactive dyeing of cotton fabrics. The salt samples recovered from Mendota, California (>98.8% sodium sulfate), cause little color difference in the dyeing with selected reactive dyes. The purified salt (III) (99.91% sodium sulfate) is more applicable for reactive dyeing of cotton fabrics since it has no deleterious effect. The recovered sodium sulfate from certain areas in the valley could not be employed in reactive dyeing due to the high level of impurities present.
Jung
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J
Division of Textiles and Clothing, University of California, Davis 95616, USA.
Sun
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D000383:Agriculture; D004396:Coloring Agents; D003247:Conservation of Natural Resources; D003460:Crystallization; D005240:Feasibility Studies; D003368:Gossypium; D012965:Sodium Chloride / Q000737:chemistry; D013431:Sulfates / Q000737:chemistry*; D013783:Textile Industry; D014865:Waste Disposal, Fluid
D004396:Coloring Agents; D013431:Sulfates; C012036:sodium sulfate; D012965:Sodium Chloride