Corrosion-inhibiting deicers derived from biomass
View Patent ↗In some variations, the invention provides a deicer composition comprising alkali acetate, a solvent (such as water) for the alkali acetate, and a corrosion inhibitor comprising lignin or a lignin derivative. The acetate and the lignin or lignin derivative are preferably each derived from the same biomass feedstock. In some embodiments, the alkali is selected from the group consisting of potassium, sodium, magnesium, calcium, and combinations thereof. In some embodiments, the alkali acetate is present in a concentration from about 30 wt % to about 99 wt %. Deicer products may be a crystallized or dried form of the deicer composition.
1. A process for producing a deicer composition, said process comprising:
(a) treating a biomass feedstock in the presence of an acidic, neutral, or alkaline solution to solubilize at least a portion of said biomass, thereby producing an extract liquor;
(b) adjusting the pH of said extract liquor to a selected first pH of about 4.8 or less, thereby producing an acidified extract liquor comprising acetic acid and lignin or lignin derivatives;
(c) separating dissociated acetic acid from said acidified extract liquor to form a dilute organic acid solution;
(d) combining said dilute organic acid solution with an alkali oxide, alkali hydroxide, and/or alkali carbonate, wherein said alkali is selected from the group consisting of potassium, sodium, magnesium, calcium, and combinations thereof, to adjust the pH to a selected second pH of at least about 3.8, thereby producing an organic salt solution comprising alkali acetate and said lignin or lignin derivatives; and
(e) concentrating said organic salt solution to a concentration of at least about 25 wt % organic salts, thereby producing a deicer composition comprising said alkali acetate and said lignin or lignin derivatives.
2. The process of claim 1 , wherein said treating in step (a) comprises extraction using steam or hot water, optionally with one or more additives or catalysts.
3. The process of claim 1 , wherein said treating in step (a) comprises extraction using sulfur dioxide, wtaer, and a solvent for lignin.
4. The process of claim 1 , wherein said selected first pH is less than about 3.8.
5. The process of claim 1 , wherein said lignin or a lignin derivative is present in said deicer composition at a concentration of about 0.01 wt % or higher.
6. The process of claim 4 , wherein said lignin or a lignin derivative is present in said deicer composition at a concentration of from about 0.1 wt % to about 2.5 wt %.
7. The process of claim 1 , wherein said dilute organic acid solution comprises from about 0.05 wt % to about 4 wt % acetic acid.
8. The process of claim 1 , said process further comprising purification of said deicer composition to produce a purified deicer composition, wherein said purification comprises a step selected from the group consisting of ion exchange, activated-carbon treatment, filtration, crystallization, and combinations thereof.
9. The process of claim 1 , said process further comprising introducing an additional amount of lignin or lignin derivatives to said deicer composition.
10. The process of claim 1 , wherein said organic salt solution or said deicer composition is crystallized to at least 99 wt % purity.