Abstract: Water purification systems include a concentrate filtration membrane and an electrodeionization unit. A concentrate effluent stream from the electrodeionization unit is filtered in the concentrate filtration membrane; the filtered concentrate effluent stream is provided to concentrating compartments of the electrodeionization unit.

Abstract: Water purification systems include a reverse osmosis unit, a treatment unit, and an electrodeionization unit. A reverse osmosis reject stream from the reverse osmosis unit is treated in the treatment unit and provided to concentrating compartments of the electrodeionization unit.

Abstract: A deoxygenation process includes the steps of adding hydrazine to a liquid containing dissolved oxygen, passing the liquid through a bed of activated carbon to catalyze a reaction between the dissolved oxygen and hydrazine whereby carbon contaminants are added to the liquid, and removing the contaminants. In another embodiment, unreacted hydrazine that remains in the liquid following the catalysis is removed by passing the liquid through an ion exchange resin. In still another embodiment, an activated carbon-catalyzed deoxygenation process employing hydrazine is practiced on a mobile platform and the process further includes the steps of transporting the apparatus to a regenerating station for regeneration. The invention also includes apparatus for carrying out the process.

Abstract: A process for treating wash water from the manufacture of terephthalic acid, wherein the wash water includes terephthalic acid, metal catalyst, and organic acid byproducts. The process includes the steps of passing the wash water through a filter medium to remove undissolved terephthalic acid solids, passing the filtered water through a cation exchange resin in hydrogen ion form to remove the metal catalysts, and passing the water through an anion exchange resin to remove dissolved terephthalic acid and dissolved organic acid byproducts. The treated water and certain components removed from the wash water are recovered and reused in the manufacture of additional terephthalic acid. An apparatus in which the process is practiced is also described and, after a quantity of wash water has been treated, the apparatus is regenerated with regenerants that are also recovered and reused in the manufacture of additional terephthalic acid.

Abstract: A mobile fluid purification unit comprises a plurality of treatment tanks mounted on a skid and interconnected by hoses for series flow, parallel flow or a combination of series and parallel flow for carrying out a variety of treatments of the liquid. A plurality of such mobile units can be mounted on a larger vehicle and connected to one another by one or several hoses to provide greater capacity and variety than is possible in a single mobile unit. A cover which may include a heater can be provided for the unit or units.

Abstract: A deoxygenation process includes the steps of adding hydrazine to a liquid containing dissolved oxygen, passing the liquid through a bed of activated carbon to catalyze a reaction between the dissolved oxygen and hydrazine whereby carbon contaminants are added to the liquid, and removing the contaminants. In another embodiment, unreacted hydrazine that remains in the liquid following the catalysis is removed by passing the liquid through an ion exchange resin. In still another embodiment, an activated carbon-catalyzed deoxygenation process employing hydrazine is practiced on a mobile platform and the process further includes the steps of transporting the apparatus to a regenerating station for regeneration. The invention also includes apparatus for carrying out the process.

Abstract: A process for treating wash water from the manufacture of terephthalic acid, wherein the wash water includes terephthalic acid, metal catalyst, and organic acid byproducts. The process includes the steps of passing the wash water through a filter medium to remove undissolved terephthalic acid solids, passing the filtered water through a cation exchange resin in hydrogen ion form to remove the metal catalysts, and passing the water through an anion exchange resin to remove dissolved terephthalic acid and dissolved organic acid byproducts. The treated water and certain components removed from the wash water are recovered and reused in the manufacture of additional terephthalic acid. An apparatus in which the process is practiced is also described and, after a quantity of wash water has been treated, the apparatus is regenerated with regenerants that are also recovered and reused in the manufacture of additional terephthalic acid.

Abstract: A process for purifying vinyl acetate contaminated with acetic acid, coloration agents, water, and/or cations and anions. A first stage consists of removing acetic acid from a vinyl acetate feed by dehydrating a commercially-available anion exchange resin by means of azeotropic distillation and passing the feed through a bed of the dehydrated resin. A second stage can consist of removing coloration agents by passing the vinyl acetate feed through a bed of activated carbon. A third stage can consist of removing water by passing the vinyl acetate feed through a bed of desiccant. A fourth stage can consist of removing cations and anions by passing the vinyl acetate feed through separate cation exchange resin and anion exchange resin beds or through a mixed resin bed.

Abstract: A mobile system for purifying liquids, such as water, including a truck trailer in which multiple purification treatment tanks are mounted. The system includes an inlet, an outlet, conductivity measuring equipment for monitoring the quality of the purified liquid, and specially designed liquid conduits and valves which permit the treatment tanks to be operated in series, in parallel, or in series/parallel. The treatment tanks can be filled with any desired purification material. The trailer is enclosed and heated to protect the system from cold temperatures.

Abstract: A process for purifying vinyl acetate contaminated with acetic acid, coloration agents, water, and/or sodium chloride. The first stage consists of removing acetic acid by passing the vinyl acetate feed through a dehydrated anion exchange resin bed. The second stage consists of removing coloration agents by passing the vinyl acetate feed through a bed of activated carbon. The third stage consists of removing water by passing the vinyl acetate feed through a bed of desiccant. The fourth stage consists of removing sodium chloride by passing the vinyl acetate feed through separate cation exchange resin and anion exchange resin beds or through a mixed resin bed.