Abstract: A stable system for producing liquid products such as ethanol, butanol and other chemicals from syngas components contacts CO or a mixture of CO2 and H2 with a highly porous side of an asymmetric membrane under anaerobic conditions and transferring these components into contact with microorganisms contained within bio-pores of the membrane. The membrane side of the membrane utilizes a dense layer to control hydration of the bio-pores with a liquid phase. The gas feed directly contacts the microorganisms in the bio-pores and maximizes their utilization of the syngas. Metabolic products produced by the microorganisms leave the membrane through the side opposite the entering syngas. This system and method establishes a unitary direction across the membrane for the supply of the primary feed source to the microorganisms and the withdrawal of metabolically produced products. The feed and product flow improves productivity and performance of the microorganism and the membrane.

Abstract: Ethanol and other liquid products produced by the contacting CO and/or a mixture of CO2 and H2 with a microorganism in a bioreactor are separated using a combination of distillation and vapor permeation membranes. The bioreactor passes an effluent with an ethanol concentration of 1 to 6 wt % to a distillation column that produces an overhead vapor stream enriched in ethanol. A series of vapor permeation membranes retain ethanol as retentate and produce a 99 wt % or higher ethanol product. Ethanol depleted permeate streams flow back to the column and the bioreactor. Coupling a bioreactor with distillation and pervaporation efficiently and economically separates ethanol when present at low concentration in an aqueous fermentation broth. The separation arrangement may also include a flash zone ahead of the distillation column to raise the concentration of the ethanol in the input stream to the distillation column.

Abstract: A membrane supported bioreactor arrangement and method for anerobic conversion of gas into liquid products including membrane modules having hollow fibers, each of the hollow fibers formed from an asymmetric membrane wall having a porous outer layer defining biopores for retaining a porous biolayer about the outer surface of the membrane wall and a less permeable hydration layer around the hollow fiber lumen; a membrane vessel for retaining the membrane modules in a process gas for formation of the biolayer on the outer surface of the hollow fiber wall by interaction of microorganisms with a process gas and for the production of a liquid product, wherein the membrane vessel retains the membrane modules in a common horizontal plane; provides a seal between contents of the membrane tank and ambient atmosphere; and includes a liquid supply conduit for communicating the process liquid with the hollow fiber lumens of the hollow fibers.

Abstract: A modular membrane supported bioreactor for anaerobic conversion of gas into liquid products including membrane module(s) having a plurality of hollow fibers packed across a cross sectional area of the membrane module in a direction transverse to the axis of the membrane module; a membrane vessel for retaining the membrane module(s) at least partially submerged in a process liquid and isolated from ambient atmosphere; and a gas supply conduit operably connected to the hollow fibers for supplying a process gas to the hollow fiber lumens. The gas supply conduit enables the formation of a biofilm on the outer surface of the hollow fiber wall by interaction of microorganisms with the process gas and the production of a liquid product that mixes with the process liquid.

Abstract: Ethanol and other liquid products are produced by contacting syngas components such as CO or a mixture of CO2 and H2 with a surface of a membrane under anaerobic conditions and transferring these components in contact with a biofilm on the opposite side of the membrane. These steps provide a stable system for producing liquid products such as ethanol, butanol and other chemicals. The gas fed on the membrane's gas contact side transports through the membrane to form a biofilm of anaerobic microoganisms that converted the syngas to desired liquid products. A liquid impermeable layer of the membrane assists in establishing direct gas phase contact syngas components with the microorganisms. The system can sustain production with a variety of microorganisms and membrane configurations.

Abstract: Ethanol and other liquid products are produced by contacting syngas components such as CO or a mixture of CO2 and H2 with a surface of a membrane and transferring these components in contact with a biofilm on the opposite side of the membrane. These steps provide a stable system for producing liquid products such as ethanol, butanol and other chemicals. The gas fed on the membrane's gas contact side transports through the membrane to form a biofilm of anaerobic microorganisms that converted the syngas to desired liquid products. The system can sustain production with a variety of microorganisms and membrane configurations.

Abstract: Ethanol and other liquid products are produced by contacting syngas components such as CO or a mixture of CO2 and H2 with a surface of a membrane under anaerobic conditions and transferring these components in contact with a biofilm on the opposite side of the membrane. These steps provide a stable system for producing liquid products such as ethanol, butanol and other chemicals. The gas fed on the membrane's gas contact side transports through the membrane to form a biofilm of anaerobic microoganisms that converted the syngas to desired liquid products. The system can sustain production with a variety of microorganisms and membrane configurations.

Abstract: A stable continuous method for producing ethanol from the anaerobic bacterial fermentation of a gaseous substrate containing at least one reducing gas involves culturing in a fermentation bioreactor anaerobic, acetogenic bacteria in a liquid nutrient medium; supplying the gaseous substrate to the bioreactor; and manipulating the bacteria in the bioreactor by reducing the redox potential, or increasing the NAD(P)H TO NAD(P) ratio, in the fermentation broth after the bacteria achieves a steady state and stable cell concentration in the bioreactor. The free acetic acid concentration in the bioreactor is maintained at less than 5 g/L free acid. This method allows ethanol to be produced in the fermentation broth in the bioreactor at a productivity of greater than 10 g/L per day. Both ethanol and acetate are produced in a ratio of ethanol to acetate ranging from 1:1 to 20:1.

Abstract: A stable continuous method for producing ethanol from the anaerobic bacterial fermentation of a gaseous substrate containing at least one reducing gas involves culturing a fermentation bioreactor anaerobic, acetogenic bacteria in a liquid nutrient medium; supplying the gaseous substrate to the bioreactor; and manipulating the bacteria in the bioreactor by reducing the redox potential, or increasing the NAD(P)H TO NAD(P) ratio, in the fermentation broth after the bacteria achieves a steady state and stable cell concentration in the bioreactor. The free acetic acid concentration in the bioreactor is maintained at less than 5 g/L free acid. This method allows ethanol to be produced in the fermentation broth in the bioreactor at a productivity greater than 10 g/L per day. Both ethanol and acetate are produced in a ratio of ethanol to acetate ranging from 1:1 to 20:1.

Abstract: A stable continuous method for producing ethanol from the anaerobic bacterial fermentation of a gaseous substrate containing at least one reducing gas involves culturing a fermentation bioreactor anaerobic, acetogenic bacteria in a liquid nutrient medium; supplying the gaseous substrate to the bioreactor; and manipulating the bacteria in the bioreactor by reducing the redox potential, or increasing the NAD(P)H TO NAD(P) ratio, in the fermentation broth after the bacteria achieves a steady state and stable cell concentration in the bioreactor. The free acetic acid concentration in the bioreactor is maintained at less than 5 g/L free acid. This method allows ethanol to be produced in the fermentation broth in the bioreactor at a productivity greater than 10 g/L per day. Both ethanol and acetate are produced in a ratio of ethanol to acetate ranging from 1:1 to 20:1.

Abstract: A novel controlled release device employing microporous membranes with or without a nonporous coating and aqueous-organic partitioning of the bioreactive substances to be delivered is provided. Devices and methods for delivering pharmaceuticals, pest-control substances, hormones, nutrients and fragrances to humans, animals or any environment are also provided.

Abstract: A novel controlled release device employing microporous membranes with or without a nonporous coating and aqueous-organic partitioning of the bioreactive substances to be delivered is provided. Devices and methods for delivering pharmaceuticals, pest-control substances, hormones, nutrients and fragrances to humans, animals or any environment are also provided.