DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Claim 6 withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 25 February 2026.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1–5 is/are rejected under 35 U.S.C. § 103 as being unpatentable over CN 109851603; hereinafter “CN’603”) in view of WO 2014/097311 (hereinafter “WO’311”) and further in view of Lee et al. (US 2012/0277493; hereinafter “US’493”).
CN’603 discloses an ethyl maltol preparation system including a crystallization device and an ethanol mother liquor recovery device, where ethanol mother liquor obtained after crystallization contains ethyl maltol and ethanol, and the ethanol mother liquor is distilled to recover ethanol for reuse in crystallization. See CN’603, lines 61–65 and 77–82. CN’603 further discloses that the ethanol mother liquor recovery device includes a crude ethanol tank, ethanol feed pump, distillation column, tower-bottom reboiler, waste liquid tank, tower-top condenser, fraction tank, and recovered ethanol finished product tank. See CN’603, lines 63–64 and 101–105.
WO’311 discloses ethanol purification by multiple distillation stages, including rectification distillation, and teaches treating a rectified ethanol stream with an elemental hydroxide, such as sodium hydroxide, potassium hydroxide, calcium hydroxide, or an equivalent hydroxide, to adjust the pH to 7–11, improve stream quality, eradicate acidity, and remove congeners such as acids and fusel oils. See WO’311, lines 113–138. WO’311 further teaches that hydroxide treatment of rectified ethanol diminishes acetal formation caused by reaction of acetaldehyde and ethanol and improves quality by eradicating acidity. See WO’311, lines 198–199 and 319–322.
US’493 discloses an ethanol recovery process using secondary reactors for hydrolysis of acetal in connection with multiple distillation columns. US’493 teaches that a crude ethanol product containing ethanol, water, ethyl acetate, acetaldehyde, acetic acid, and diethyl acetal may be hydrolyzed in a secondary reactor, then separated in a first column, and then the residue may be further processed to recover ethanol. See US’493, lines 608–623.
US’493 further teaches that the secondary reactor location may vary, that multiple secondary reactors may be used, and that such reactors may be located before the first column, as a side-car reactor attached to a column, as an integrated reactor in a reboiler loop, or in a residue stream between the first and second column. See US’493, lines 623–630, 851–861, and 1088–1094. US’493 also teaches that a second column can concentrate ethanol overhead, with the overhead withdrawn, condensed, and refluxed. See US’493, lines 909–936.
Claim 1 recites a device for distillation decolorization and purification of alcohol in maltol production comprising a rectification column, an alkali hydrolysis kettle, and an alkali hydrolysis rectification column, with the upper outlet of the rectification column connected to the alkali hydrolysis kettle, the outlet of the alkali hydrolysis kettle connected to the alkali hydrolysis rectification column, and the upper outlet of the alkali hydrolysis rectification column connected to a finished product tank.
CN’603 teaches the same or closely analogous field of recovering ethanol from ethyl maltol crystallization mother liquor and reusing the recovered ethanol in crystallization. CN’603’s ethanol recovery device includes a crude ethanol tank, ethanol feed pump, distillation column, tower-bottom reboiler, overhead condenser, fraction tank, and recovered ethanol finished product tank, with the ethanol feed pump feeding ethanol mother liquor into the distillation tower and the overhead condenser and fraction tank collecting recovered ethanol. See CN’603, lines 61–65, 98–105, and claim 1 at line 126.
CN’603 does not expressly disclose an alkali hydrolysis kettle positioned between the first distillation/rectification column and a downstream alkali hydrolysis rectification column. However, WO’311 teaches treating rectified ethanol with hydroxide, including sodium hydroxide or potassium hydroxide, to adjust pH, remove acidity, improve ethanol quality, and reduce acetal formation. See WO’311, lines 135–138 and 198–199. US’493 teaches using a secondary hydrolysis reactor in an ethanol recovery train and expressly teaches that such a reactor may be placed before a first column, attached to a column as a side-car reactor, included in a reboiler loop, or positioned in the residue stream between first and second columns. See US’493, lines 623–630 and 1088–1094.
It would have been obvious to one of ordinary skill in the art to modify CN’603’s same-field ethanol mother-liquor recovery system by adding a hydroxide-treatment/hydrolysis vessel downstream of the first distillation/rectification column and upstream of a further rectification column, as taught by WO’311 and US’493, in order to improve recovered ethanol quality by removing acidity and reducing impurity formation while placing the treatment reactor in a known location in a multi-column ethanol recovery train. The combination would have involved the predictable use of known ethanol recovery equipment and known hydroxide treatment to improve recovered ethanol quality. Accordingly, claim 1 is obvious over CN’603 in view of WO’311 and US’493.
Claim 2 further recites first, second, and third condensers, with the first condenser connected to the upper outlet of the rectification column, the alkali hydrolysis tank/kettle connected to the second condenser through a circulation pipeline, and the upper outlet of the alkali hydrolysis rectification column connected to the third condenser.
CN’603 expressly teaches an overhead condenser connected to the top gaseous outlet of the ethanol recovery distillation tower, with the liquid-phase outlet of the overhead condenser connected to a fraction tank. See CN’603, lines 101–105 and claim 1 at line 126. US’493 teaches a second column that forms an overhead stream which may be condensed and refluxed. See US’493, lines 920–936 and 1296–1302. US’493 also teaches secondary reactors associated with distillation columns, including a side-car reactor and an integrated reboiler-loop reactor. See US’493, lines 851–861 and 1234–1238.
It would have been obvious to provide condensers at the overhead outlets of the first and downstream rectification columns in the modified CN’603 device, because CN’603 already uses an overhead condenser for ethanol recovery and US’493 teaches condensing and refluxing overhead streams in multi-column ethanol recovery. It would also have been obvious to include heat-exchange or condensing equipment in circulation with the intermediate hydroxide-treatment/hydrolysis vessel to maintain desired process temperature and phase conditions during ethanol treatment. Accordingly, claim 2 is obvious over CN’603 in view of WO’311 and US’493.
Claim 3 further recites that the other end of the first condenser is connected to a reflux tank, an outlet of the reflux tank is connected to the rectification column through a first reflux pump, and a lower part of the rectification column is connected to a first reboiler through a circulation pipeline.
CN’603 teaches that the overhead condenser liquid-phase outlet is connected to a fraction slot, and that the fraction slot is connected to a recovered ethanol finished product tank. CN’603 further teaches a reflux line from the fraction slot back to the side wall of the distillation tower, with a liquid level control arrangement to maintain partial reflux. See CN’603, lines 101–106 and 102–105. CN’603 also teaches that the tower-bottom reboiler is connected to the liquid-phase outlet of the distillation tower and that the reboiler gas-phase outlet is connected to the gas-phase inlet of the distillation tower to return reboiled alcohol vapor to the tower. See CN’603, lines 101–105 and 108–112.
Although CN’603 uses the term “fraction slot” rather than “reflux tank,” the structure receives condensed overhead liquid and supplies reflux to the distillation tower. Providing a pump in the reflux return line would have been an obvious design choice for controlled liquid return in a distillation recovery system, particularly because CN’603 already uses pumps to feed ethanol into the distillation tower and teaches controlled partial reflux from the fraction slot. See CN’603, lines 101–106. Accordingly, claim 3 is obvious over CN’603 in view of WO’311 and US’493.
Claim 4 further recites that the other end of the third condenser is connected to a finished product tank, an outlet of the finished product tank is connected to the alkali hydrolysis rectification column through a second reflux pump, a lower part of the alkali hydrolysis rectification column is connected to a second reboiler through a circulation pipeline, and the bottom of the alkali hydrolysis rectification column is connected to a second extraction pump.
CN’603 teaches a recovered ethanol finished product tank connected downstream of the overhead condenser and fraction slot. See CN’603, lines 61–64 and 101–105. US’493 teaches a second distillation column that concentrates ethanol overhead, withdraws overhead in a line, and condenses and refluxes at least a portion of the overhead. See US’493, lines 909–936 and 1296–1302. CN’603 also teaches a tower-bottom reboiler and a waste-liquid tank connected to the bottom outlet of the distillation tower, showing conventional bottom heating and bottom residue removal in ethanol recovery. See CN’603, lines 101–105 and 108–112.
It would have been obvious to apply CN’603’s condenser/fraction/product-tank arrangement and tower-bottom reboiler/waste-removal arrangement to the downstream rectification column added according to US’493. Such a downstream column would predictably require overhead condensation/reflux, product collection, reboiling, and bottom residue removal to perform ethanol rectification. Accordingly, claim 4 is obvious over CN’603 in view of WO’311 and US’493.
Claim 5 recites the complete device including a first feed pump, first condenser, reflux tank, first reflux pump, first reboiler, first extraction pump, second condenser, alkali hydrolysis receiving tank, second feed pump, third condenser, finished product tank, second reflux pump, second reboiler, and second extraction pump, with specified connections among the rectification column, alkali hydrolysis kettle, alkali hydrolysis receiving tank, alkali hydrolysis rectification column, and finished product tank.
CN’603 teaches the same-field ethanol recovery system for ethyl maltol production, including the crude ethanol tank, ethanol feed pump, distillation tower, tower-bottom reboiler, waste liquid tank, overhead condenser, fraction slot, and recovered ethanol finished product tank. See CN’603, lines 61–65, 98–105, and claim 1 at line 126. CN’603 further teaches feeding recovered ethanol mother liquor to the distillation tower using the ethanol feed pump, overhead condensation, collection in a fraction slot, partial reflux back to the distillation tower, and collection in a recovered ethanol finished product tank. See CN’603, lines 101–106.
WO’311 supplies the hydroxide-treatment teaching, namely treating rectified ethanol with sodium hydroxide, potassium hydroxide, calcium hydroxide, or an equivalent hydroxide to adjust pH, remove acidity, improve quality, and reduce acetal formation. See WO’311, lines 135–138, 198–199, and 319–322. US’493 supplies the predictable placement and use of a secondary hydrolysis reactor in a multi-column ethanol recovery train, including reactor placement before a first column, as a side-car reactor, in a reboiler loop, or between first and second columns. See US’493, lines 623–630, 851–861, and 1088–1094. US’493 also teaches using a second column to concentrate ethanol overhead, with overhead condensation and reflux. See US’493, lines 909–936 and 1296–1302.
It would have been obvious to one of ordinary skill in the art to modify CN’603’s ethanol recovery device by adding an intermediate hydroxide-treatment/hydrolysis vessel and receiving tank between the first ethanol recovery column and a downstream rectification column, as suggested by WO’311’s hydroxide treatment of rectified ethanol and US’493’s secondary-reactor placement in ethanol recovery systems. The use of feed pumps, extraction pumps, condensers, reboilers, reflux tanks, reflux pumps, receiving tanks, and product tanks would have been a predictable implementation of conventional distillation and ethanol recovery hardware in the modified system. The motivation would have been to improve recovered ethanol quality, reduce acidity and impurity formation, and recover reusable ethanol from an ethyl maltol/maltol-type crystallization mother liquor. Accordingly, claim 5 is obvious over CN’603 in view of WO’311 and US’493.
/DEBORAH D CARR/Primary Examiner, Art Unit 1691
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