INSTRUMENT FOR DETERMINING PERMEATION RATES THROUGH A MEMBRANE

• US 3,590,634 A
• Filed: 05/05/1969
• Issued: 07/06/1971
• Est. Priority Date: 05/05/1969
• Status: Expired due to Term

• Current Assignee: Jan F. Schimscheimer, Raphael A. Pasternak
• Original Assignee: Jan F. Schimscheimer, Raphael A. Pasternak
• Inventors: Pasternak, Raphael A., Schimscheimer, Jan F.
• Application Number:
  US04/821,905
• Time in Patent Office: 792 Days
• US Class Current: 374/54
• CPC Class Codes: G01N 15/08 Investigating permeability, pore-volume, or surface area of porous materials

Abstract

An instrument for determining permeation rates through a membrane having a permeation cell with upstream and downstream compartments arranged to hold a membrane therebetween, a line for continuously passing a gaseous permeant to the upstream cell compartment and from thence to the atmosphere, a line for passing a current of a carrier gas first to the downstream cell compartment and then to a permeant detector associated with a recorder, a bypass line for sending the carrier gas around the downstream compartment, as controlled by a valve in the line, and a heater for making controlled variations in the temperature of the permeation cell during the course of any given permeation rate test.

Claims

1. An instrument for determining permeation rates through a membrane comprising a permeation cell having upstream and downstream compartments separated by a membrane clamped within the cell, a line for continuously passing a gaseous permeant to the upstream cell compartment and from thence to the atmosphere, a line for passing a current of a carrier gas first to the downstream cell compartment and then to a permeant detector means for effecting a substantially continuous determination of the relative amount of permeant in any carrier gas stream passed through said detector means, and associated with a recorder, a bypass line permitting the carrier gas to be detoured around the downstream compartment as the latter is periodically shut off from the system, and means for making controlled variations in the temperature of the permeation cell while continuously making the aforesaid determination when continuously passing the gaseous permeant to the upstream cell compartment and the carrier gas to the detector via the downstream compartment.

2. An instrument as recited in claim 1 which includes means for injecting a supply of liquid permeant into the upstream cell compartment.

3. An instrument for measuring the permeation rate of a gaseous or liquid permeant through a membrane, said instrument comprising:

a permeation cell having upstream and downstream compartments arranged to be separated by the membrane under study;

clamping means for holding said membrane in position within the cell and for sealing the membrane portion separating the cell compartments from contact with the atmosphere;

permeant-receiving means leading into the upstream cell comparTment through which the latter may be provide with permeant during the period of the test, and exhaust means communicating with the atmosphere leading from said upstream compartment;

a first carrier gas-receiving line leading into the downstream cell compartment, said line incorporating valve means adapted to effect precise control of the rate at which carrier gas, under atmospheric pressure, is passed through said line;

a second carrier gas-receiving line incorporating valve control means leading into the upstream cell compartment;

an exit line incorporating valve control means leading from the downstream cell compartment and communicating with detecting means for effecting a substantially continuous determination of the relative amount of permeant in any carrier gas stream passed through said detecting means, and recording means associated with said detection means for displaying the permeant content data so obtained;

means for making controlled variations in the temperature of the permeation cell while continuously making the aforesaid determination of the relative amount of permeant in the carrier gas stream passed through the detecting means; and

a bypass line incorporating valve control means and communicating with said first carrier gas line and with said exit line whereby the carrier gas stream may be shunted around the downstream compartment during any period in which the latter is closed off from the system.