1. A process for the separation of at least one di-carboxylic acid compound from a mixture comprising at least one mono-carboxylic acid compound and at least one di-carboxylic acid compound, the process comprising the steps of:
(a) contacting the mixture with an ion exchange chromatography medium to cause at least one mono-carboxylic acid compound and at least one di-carboxylic acid compound to be retained by the ion exchange chromatography medium;
(b) eluting at least one mono-carboxylic acid compound from the ion exchange chromatography medium using a first eluent to form a first eluate; and
(c) eluting at least one di-carboxylic acid compound from the ion exchange chromatography medium using a second eluent to form a second eluate;
wherein the first eluate is enriched in at least one mono-carboxylic acid compound retained by the medium relative to the concentration of such acid in the first eluent, the second eluate is enriched in a least one di-carboxylic acid compound retained by the medium relative to the concentration of such acid in the second eluent, and at least one eluent comprises an organic acid.
2. The process of claim 1, wherein the ion exchange chromatography medium is an anion exchange chromatography medium.
3. The process of claim 1, wherein the first eluent comprises an organic acid having a pKa equal to or greater than about 3.7.
4. The process of claim 2, wherein the second eluent comprises an organic acid having a pKa equal to or greater than about 3.7.
5. The process of claim 1, wherein each of the first eluent and the second eluent comprise an organic acid.
6. The process of claim 1, wherein each of the first eluent and the second eluent comprise an organic acid, and wherein the organic acid is acetic acid.
7. The process of claim 1, wherein the at least one mono-carboxylic acid compound is selected from the group consisting essentially of C6 mono-carboxylic acid compounds and the at least one di-carboxylic acid compound is selected from the group consisting essentially of C6 di-carboxylic acid compounds.
8. The process of claim 1, wherein the ion exchange chromatography medium is selected from the group consisting of Mitsubishi Diaion WA30, Mitsubishi Diaion WA20, Mitsubishi Diaion UBA100S, Mitsubishi Diaion UMA150, Mitsubishi Diaion UMA130J, Mitsubishi Diaion SA21, Finex AS532, Finex AS510, and Dowex Retardion 11A8.
9. The process claim 1, wherein each of the first and second eluent comprise formic acid.
10. The process of claim 1, wherein the ion-exchange chromatography is carried out using simulated moving bed (SMB) chromatography.
11. The process of claim 1, wherein the eluting is carried out using isocratic elution conditions or gradient elution conditions.
12. The process of claim 1, wherein the mixture is derived from the oxidation of glucose.
13. A process for the separation of at least one mono-carboxylic acid compound or at least one di-carboxylic acid compound from a mixture, the process comprising the steps of:
(a) contacting the mixture with an ion exchange chromatography medium to cause at least one mono-carboxylic acid compound or at least di-carboxylic acid compound to be retained by the ion exchange chromatography medium; and,
(b) eluting at least one of the at least one mono-carboxylic acid compound or the at least one di-carboxylic acid compound from the ion exchange chromatography medium using an eluent to form an eluate;
wherein the eluate is enriched in one of the at least one mono-carboxylic acid compound or the at least one di-carboxylic acid compound retained by the medium relative to the concentration of such eluted acid in the remainder of the mixture having contacted the medium and wherein the eluent comprises an organic acid.
14. The process of claim 13, wherein the retained acid compound is at least one mono-carboxylic acid compound.
15. The process of claim 13, wherein the retained acid compound is at least one di-carboxylic acid compound.
16. The process of claim 13, wherein the organic acid has a pKa of at least about 3.7.
17. The process of claim 13, wherein the organic acid is acetic acid.
18. The process of claim 17, wherein the eluent further comprises water.
19. A process for the production of an adipic acid product, the process comprising the steps of oxidizing glucose to produce a mixture comprising at least one mono-carboxylic acid compound and at least one di-carboxylic acid compound, separating at least one mono-carboxylic acid compound in the mixture from at least one di-carboxylic acid compound in the mixture by the process of claim 1, and converting at least a portion of at least one di-carboxylic acid separated from the mixture to an adipic acid product.
20. The process of claim 1, wherein the separation process is carried out at a temperature between 0\xb0 C. and 100\xb0 C.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An apparatus, comprising:
an analog input node configured to receive an analog signal;
a plurality of comparators coupled to the analog input node and configured to convert the analog signal to a digital signal;
a frequency detection block configured to receive the digital signal and analyze a frequency content of the digital signal; and
a controller coupled to the plurality of comparators and to the frequency detection block, wherein the controller is configured to:
dynamically determine a window size for converting the analog signal based, at least in part, on an output of the frequency detection block, wherein determining the window size comprises:
increasing the window size when the frequency detection block detects a high magnitude of changes; and
decreasing the window size when the frequency detection block detects a low magnitude of changes;
determine a window position for converting the analog signal; and
turn on comparators of the plurality of comparators within a window defined by the determined window size and the determined window position.
2. The apparatus of claim 1, wherein the controller is further configured to update the window size for converting the analog signal by dynamically determining a second window size for converting the analog signal.
3. (canceled)
4. (canceled)
5. The apparatus of claim 4, wherein the frequency detection block comprises a high-pass filter (HPF).
6. The apparatus of claim 5, wherein the high-pass filter (HPF) has a transfer function of approximately 1\u2212z\u22121.
7. The apparatus of claim 4, wherein the frequency detection block comprises a band-pass filter (BPF).
8. The apparatus of claim 4, wherein the controller is further configured to:
increase the window size when the frequency detection block output is above a first threshold; and
decrease the window size when the frequency detection block output is below a second threshold.
9. (canceled)
10. The apparatus of claim 1, wherein the controller is configured to increase the window size by turning on additional comparators of the plurality of comparators, and wherein the controller is configured to decrease the window size by turning off comparators of the plurality of comparators.
11. The apparatus of claim 1, wherein the controller is further configured to dynamically determine the window position from a previous window position to a new window position by:
calculating a correction value based, at least in part, on the frequency detection block output; and
adding the correction value to the previous window position to obtain the new window position.
12. A method, comprising:
converting an analog signal to a digital signal with a plurality of comparators, wherein a first portion of the plurality of comparators are activated and a second portion of the plurality of comparators are not activated, and wherein the first portion of comparators is defined by a window size and a window position;
dynamically determining the window size for the first portion of comparators based, at least in part, on the digital signal, wherein the window size determines a quantity of the plurality of comparators in the first portion, wherein the step of dynamically determining the window size comprises:
detecting a magnitude of changes in the digital signal; and
adjusting the window size based on the magnitude of changes in the digital signal by:
decreasing the window size when a low magnitude of changes is detected in the digital signal; and
increasing the window size when a high magnitude of changes is detected in the digital signal; and
determining the window position for the first portion of comparators based, at least in part, on the digital signal, wherein the window position determines which of the plurality of comparators are in the first portion.
13. The method of claim 12, further comprising updating the window size for the first portion of comparators by dynamically determining a second window size.
14. The method of claim 12, wherein the step of updating the window size comprises dynamically determining the window size based, at least in part, on a frequency input content of the digital signal.
15. (canceled)
16. (canceled)
17. The method of claim 12, wherein the step of decreasing the window size comprises turning off comparators of the plurality of comparators, and wherein the step of increasing the window size comprises turning on comparators of the plurality of comparators.
18. The method of claim 12, wherein the step of detecting the magnitude of changes comprises performing high-pass filtering on the digital signal.
19. The method of claim 18, wherein the step of adjusting the window size comprises:
increasing the window size when an output of the high-pass filtering is above a first threshold; and
decreasing the window size when the output of the high-pass filtering is below a second threshold.
20. The method of claim 12, wherein the step of detecting the magnitude of changes comprises performing band-pass filtering on the digital signal.
21. The method of claim 12, further comprising adjusting the window position from a previous window position to a new window position by:
calculating a correction value based, at least in part, on the detected frequency changes in the digital signal; and
adding the correction value to the previous window position to obtain the new window position.
22. An apparatus, comprising:
a plurality of comparators configured to convert an analog signal to a digital signal;
a processing block configured to receive the digital signal and configured to determine a frequency input content of the digital signal, wherein the processing block comprises a frequency detection block; and
a controller coupled to the processing block and coupled to the plurality of comparators, wherein the controller is configured to:
dynamically determine a window size for converting the analog signal based, at least in part, on an indication of the frequency input content of the digital signal received from the processing block, wherein determining the window size comprises:
increasing the window size when the processing block detects a high magnitude of changes; and
decreasing the window size when the processing block detects a low magnitude of changes;
determine a window position for converting the analog signal; and
turn on comparators of the plurality of comparators within a window defined by the determined window size and the determined window position.
23. (canceled)
24. The apparatus of claim 22, further comprising:
a sparkle code correction block coupled to the digital signal output by the plurality of comparators; and
a thermocode decode block coupled to the sparkle code correction.
25. (canceled)
26. The apparatus of claim 22, wherein the processing block comprises a high-pass filter (HPF), and wherein the controller is configured to:
increase the window size when the high-pass filter (HPF) output is above a first threshold; and
decrease the window size when the high-pass filter (HPF) output is below a second threshold.
27. The apparatus of claim 26, wherein the controller is configured to increase the window size by turning on comparators of the plurality of comparators, and wherein the controller is configured to decrease the window size by turning off comparators of the plurality of comparators.
28. The apparatus of claim 22, wherein the controller comprises:
a digital output tracking and prediction block configured to determine a portion of the plurality of comparators to activate; and
an analog-to-digital converter (ADC) control sequence block configured to generate a control sequence to activate the portion of the plurality of comparators.