A two-stage pretreatment using dilute sodium hydroxide solution followed by an ionic liquid at low temperatures: Toward construction of lignin-first biomass pretreatment

2019 ◽  
Vol 7 ◽  
pp. 100286 ◽  
Author(s):  
Mingkun Yang ◽  
Xin Zhang ◽  
Gang Cheng
Keyword(s):  
Ionic Liquid ◽  
Sodium Hydroxide ◽  
Low Temperatures ◽  
Sodium Hydroxide Solution ◽  
Biomass Pretreatment ◽  
Two Stage ◽  
Hydroxide Solution ◽  
Dilute Sodium Hydroxide

The preparation of sodium 4-Amino-3-nitro-benzenesulfonate and some related compounds

1982 ◽  
Vol 35 (8) ◽  
pp. 1727 ◽  
Author(s):  
J Rosevear ◽  
JFK Wilshire
Keyword(s):  
Sodium Hydroxide ◽  
Nitro Group ◽  
Sodium Salt ◽  
Sulfonic Acid ◽  
Sodium Hydroxide Solution ◽  
Hydroxide Solution ◽  
Dilute Sodium Hydroxide ◽  
Related Compounds

The sodium salt of 4-amino-3-nitrobenzenesulfonic acid (O-nitroaniline-p-sulfonic acid) has been prepared by the action of dilute sodium hydroxide solution on ethyl [(4-chlorosulfonyl-2-nitro)- phenyllcarbamate. Central to this synthesis is the finding that the N-ethoxycarbonyl group, when located ortho to a nitro group (but not to a bromo group), is readily removed by dilute sodium hydroxide solution.

Reactions of some 2-aminophenyl- and 2- and 4-nitrophenyl sulfones in aqueous sodium hydroxide solution

1970 ◽  
Vol 48 (9) ◽  
pp. 1394-1403 ◽  
Author(s):  
K. B. Shaw ◽  
R. K. Miller
Keyword(s):  
Sodium Hydroxide ◽  
Alkaline Solution ◽  
Sodium Hydroxide Solution ◽  
Aqueous Sodium Hydroxide ◽  
Major Product ◽  
Aqueous Sodium Hydroxide Solution ◽  
Aqueous Sodium ◽  
Hydroxide Solution ◽  
Orthanilic Acid ◽  
Dilute Sodium Hydroxide

When 2-aminophenylsulfonylacetic acid (3) was heated under reflux in an excess of dilute sodium hydroxide solution, the only product identified was 2-methylsulfonylaniline (6). When 2-nitrophenyl-sulfonylacetic acid was treated under the same conditions, the major products identified were 2-methyl-sulfonylnitrobenzene (7), 2-nitrophenol (8), and orthanilic acid (13); minor products of this reaction were 6 and 3-methylsulfonyl-3′-nitro-4-amino-4′-hydroxybiphenyl (12). The same products were obtained although the yields were different when 7 was boiled with alkali, but the reaction of 4-methylsulfonyl-nitrobenzene (15) with alkali was less complex and 4-nitrophenol (16) was the only major product. The biphenyl 12 was also formed in small yield when N-(2-methylsulfonylphenyl)hydroxylamine (19) was treated with alkali and its formation in these reactions was investigated in detail. It was concluded that 12 arises from 7 and 19, but it could also be prepared from 19 and 2-chloro- or better, 2-fluoronitrobenzene, in alkaline solution, and based on all these observations, a mechanism for its formation is suggested. The genesis of the various other products is also discussed. Reference is made to the infrared spectra of sulfones.

scholarly journals Study of an Evaporation System for Sodium Hydroxide Solution

2010 ◽  
pp. 35-36 ◽  
Author(s):  
Md Atikur Rahman ◽  
Nymul Ehsan Khan
Keyword(s):  
Caustic Soda ◽  
Sodium Hydroxide ◽  
Textile Industry ◽  
Chemical Engineering ◽  
Sodium Hydroxide Solution ◽  
Textile Mills ◽  
Hydroxide Solution ◽  
Dilute Sodium Hydroxide ◽  
Single Effect ◽  
Soda Solution

The textile industry in Bangladesh uses a substantial quantity of caustic soda (sodium hydroxide) to clean and prepare fabrics for dyeing. In all textile mills dealing with finishing, particularly with the mercerizing of cotton and mixed cotton fabrics, dilute caustic soda solutions come out as effluent from mercerizing unit. Caustic soda is expensive and its disposal without neutralization is unacceptable. A considerable amount of caustic soda can be saved if the dilute solution leaving the mercerizing step can be collected, concentrated and recycled. The concentration of the dilute caustic soda solution can be carried out by means of evaporation. A single effect evaporation system to concentrate the dilute sodium hydroxide solution was constructed and operated. The operating results confirm the economic viability of such recovery scheme.Journal of Chemical Engineering Vol.ChE 24 2006 35-36

Microwave Assisted Enzymatic Hydrolysis of Corn Stalks for L-Lactic Acid Production

2010 ◽  
Vol 113-116 ◽  
pp. 712-715
Author(s):  
Xue Xin Yang ◽  
Gui Zhen Fang
Keyword(s):  
Lactic Acid ◽  
Sulfuric Acid ◽  
Enzymatic Hydrolysis ◽  
Sodium Hydroxide ◽  
Acid Production ◽  
Sodium Hydroxide Solution ◽  
Lactic Acid Production ◽  
Yield Ratio ◽  
Hydroxide Solution ◽  
Dilute Sodium Hydroxide

Glucose production from pretreated corn stalks by cellulose enzymatic hydrolysis with cellulase was investigated and compared with no pretreatment, as a reference. The corn stalks were pretreated with microwave, sulfuric acid hydrolysis and dilute sodium hydroxide solution hydrolysis respectively. The enzymatic hydrolysis experiments were carried out at 50°C, 50 g/l dry matter (DM) solid substrate concentration and 15 filter paper unit (IU)/g DM of a commercial cellulase. Fermentable sugar was able to be produced from all the pretreated corn stalks with an overall yield of 29-58% of the maximum theoretical yield, based on the glucan available in the solid and liquid substrate. The corn stalks pretreated with dilute acid had the best glucose yield as 58.09% followed by the corn stalks pretreated with acid and microwave with an overall yield of 57.02% with 15 IU/g DM of cellulase. Glucose was the main product with enzymatic hydrolysis yield ratio 38.89%in the dilute sulfuric acid pretreated corn stalks, while with enzymatic hydrolysis yield ratio 51.07%in the dilute sodium hydroxide solution and microwave pretreated corn stalks under enzymatic hydrolysis conditions. These advantages, along with their negative price, make these solids a valuable raw material for L-lactic acid production.

Reactions of N-(2- and 4-methylsulfonylphenyl)hydroxylamines and 2-methylsulfonylnitrosobenzene in dilute aqueous sodium hydroxide solution

1970 ◽  
Vol 48 (9) ◽  
pp. 1404-1413 ◽  
Author(s):  
K. B. Shaw ◽  
R. M. Heggie ◽  
R. K. Miller
Keyword(s):  
Sodium Hydroxide ◽  
Room Temperature ◽  
Sodium Hydroxide Solution ◽  
Aqueous Sodium Hydroxide ◽  
Major Product ◽  
Quantitative Yield ◽  
Aqueous Sodium Hydroxide Solution ◽  
Aqueous Sodium ◽  
Hydroxide Solution ◽  
Dilute Sodium Hydroxide

When N-(2-methylsulfonylphenyl)hydroxylamine (4) was treated with dilute sodium hydroxide solution the major product was always 2,2′-di(methylsulfonyl)azoxybenzene (5). At room temperature other significant products were 2-hydroxy-2′-methylsulfonylazoxybenzene (6a) and 2-methylsulfonylnitrobenzene (2), while 6a was also formed at reflux together with small amounts of 2-hydroxy-2′-methylsulfonylazobenzene (8), 2-methylsulfonylaniline (7), 3-methylsulfonyl-3′-nitro-4-amino-4′-hydroxybiphenyl (3), and 2. The compounds 5, 6a, and 7 were also obtained when 2-methylsulfonylnitrosobenzene (9) was boiled with alkali. The decomposition of N-(4-methylsulfonylphenyl)hydroxylamine (16) in dilute alkali at room temperature gave a quantitative yield of 4,4′-di(methylsulfonyl)azoxybenzene (17) and at reflux, mixtures of 17 and 4,4′-di(methylsulfonyl)azobenzene (18) were obtained. The modes of formation of the various products from the two hydroxylamines are discussed.

scholarly journals Technology development of fatty acids obtaining from soapstok using saponification

2021 ◽  
Vol 5 (6 (113)) ◽  
pp. 16-23
Author(s):  
Natalia Sytnik ◽  
Ekaterina Kunitsia ◽  
Viktoriia Kalyna ◽  
Olena Petukhova ◽  
Kostiantyn Ostapov ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Mass Fraction ◽  
Sodium Hydroxide Solution ◽  
First Grade ◽  
Oil Refining ◽  
Two Stage ◽  
Hydroxide Solution ◽  
Total Fat

The processing of oil refining waste is essential from economic and environmental points of view. An important issue is the processing of soapstock to extract fatty acids, which are raw materials for various industries. The two-stage method of fatty acids obtaining from soapstock using saponification with sodium hydroxide solution and decomposition with sulfuric acid is investigated. The peculiarity of the work is the study of the influence of soapstock saponification conditions on the key efficiency indicators of fatty acid extraction: yield and neutralization number. A sample of soapstock was obtained as a result of alkaline neutralization of sunflower oil. Soapstock quality corresponds to DSTU 5033 (CAS 68952-95-4): mass fraction of total fat – 68.5 %, fatty acids – 62.6 %, neutral fat – 5.9 %. Rational saponification conditions were determined: duration (85 min.) and concentration of sodium hydroxide solution (45 %). After saponification, the soapstock was subjected to decomposition with sulfuric acid under the following conditions: temperature 90 °C, duration 40 min. Under the rational saponification conditions, the yield of fatty acids (91.8 %) and the neutralization number (187.1 mg KOH/g) were determined. The obtained fatty acids correspond to the first-grade fatty acids according to DSTU 4860 (CAS 61788-66-7). Acid indicators: mass fraction of moisture and volatile substances – 1.5 %, mass fraction of total fat – 98.0 %, cleavage depth – 69.2 % oleic acid. The use of the soapstock saponification stage before decomposition leads to an improvement in the quality indicators and an increase in the neutralization number of fatty acids by 4 %, yield – by 16.2 %. The results of the study make it possible to produce fatty acids from soapstock by two-stage technology with high yield and neutralization number

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