Palmitic acid. Khoom, ntau lawm, daim ntawv thov

Palmitic acid (lwm lub npe - hexadecanoic) - ib tug nyeem monocarboxylic (fatty) acid. Feem ntau nyob rau hauv cov xwm. Rau cov thawj lub sij hawm no yam khoom uas yog muaj nyob rau hauv xib-teg ntawm roj. Esters thiab ntsev ntawm no acid yog hu ua palmitate. Muaj ntau ntawm cov esters ntawm crystallinity thiab zoo li ciab. Nws muaj cov nram qab tshuaj mis: CH3 (CH2) 14COOH. Thiab nws empirical mis yog: C16H32O2.

Nrhiav palmitic acid nyob rau hauv cov xwm

Qhov no cov ntaub ntawv uas yog, raws li ib feem ntawm feem ntau ntawm cov glycerides ntawm cov roj ntawm zaub cov keeb kwm thiab tsiaj. Piv txwv li, nws muaj xws li soybean roj 6.5%, xibtes roj - 38-47%, lard - 30%. Nyob rau hauv tas li ntawd, hexadecanoic acid yog ib tug tswv cuab ntawm ib co waxes: nyob rau hauv spermaceti muaj 90% cov phev whale hexadecanoic acid cetyl ester, thiab beeswax txog 30% ee myristyl ether. Nyob rau hauv cov tsiaj muaj tus kab mob palmitic acid yog qhov kawg khoom ntawm fatty acid synthesis ntawm acetyl-CoA.

Nyob rau hauv daim ntawv ntawm cov hexadecanoic acid glyceride nyob rau hauv muaj pes tsawg leeg muaj ib tug palm roj, ib tug zaub roj Suav thiab North American txiv hmab txiv ntoo thiab Croton sebiferum Stillinga sebifera, noob Rhus succedanea (a ciab), ib tug ciab mirikonovom txiv hmab txiv ntoo Myrica cerifera, nyob rau hauv lanolin. Nyob rau hauv ib tug dawb xeev palmitic acid yog pom nyob rau hauv lub noob ntawm paprika nyob rau hauv tsis sib haum Lycopodium thiab cadaveric ciab (qhov tseem ceeb).

Lub cev thaj chaw ntawm palmitic acid:

1. mob (nyob rau hauv tus qauv tej yam kev mob) - tsis muaj kob muaju.

2. hniav puas loj yog 256, 43 g / mol.

3. Cov kev ceev yog 0,841 g / cm³.

Thermal thaj chaw ntawm palmitic acid:

1. Lub melting kub yog 62,9 ° C.

2. Lub ib kub npau npau taw tes sib npaug zos rau 105 ° C (ntawm 0.01 mmHg. V.) Thiab 167 ° C (ntawm 1 hli Hg. V.).

3. Flash point sib npaug zos rau 192 ° C.

4. Cov hniav puas tshav kub muaj peev xwm (ntawm ib txwm tej yam kev mob) yog 460 J / (mol · K).

Yuav ua li cas yog cov tshuaj thaj chaw ntawm hexadecanoic acid?

1. solubility nyob rau hauv dej yog sib npaug zos rau 0.0007 (nyob rau hauv 20 ° C).

2. solubility nyob rau hauv ethanol yog 2600 (ntawm 7,2 ° C).

3. Palmitic acid yog mob me me soluble nyob rau hauv benzene thiab acetone.

Kho qhov muag khoom ntawm palmitic acid:

1. Lub refractive index yog 1,4219.

Kev npaj ntawm palmitic acid

Qhov no tshuaj yuav tsum tau nyob rau hauv ob peb txoj kev:

1. Los ntawm fractional crystallization los yog retifikatsii los ntawm mixtures ntawm fatty acids uas tau raug npaj los ntawm saponification ntawm cov nqaijrog los yog paraffins oxidation.

2. Thaum cetyl cawv los ntawm cua sov nrog txiv qaub rau hauv lub sodium rau 270 ° C (Dumas thiab Stas).

C16H33OH (cetyl cawv) + O2 (oxygen) = C15H31COOH + H2 O (dej)

3. Thaum melting elaidic (oleic acid) nrog sodium hydroxide:

CH3 (CH2) 7CH (oleic acid) = CH (CH2) 7SOON + H2O (dej) + O = C15H31COOH (palmitic acid mis) + CH3COOH (acetic acid)

4. Yog hais tias lub nitric acid oxidation ntawm 2-oktodekanonom:

CH3 (CH2) 15-CO-CH3 + 3O (oxygen) = C15H31COOH (hexadecanoic acid) + CH3COOH (acetic acid)

5. Tsis tas li ntawd no cov ntaub ntawv uas muaj peev xwm yuav tsim los ntawm txoj kev ntawm lub cyanide yodyura pentadecylic cawv:

C15H31J + KCN (cyano compound) = kJ + C15H31-CN;

C15H31-CN (cyano compound) + 2H2O (dej) = C15H31COOH (derived tshuaj) + NH3

Qhov twg siv palmitic acid?

1. Xam tias yog hu cov ntaub ntawv uas siv nyob rau hauv qhov siv thiab ua napalm stearin (ib tug tshwj xeeb sib tov nrog stearic acid), opaque kom hniav zoo nkauj thiab ntau yam detergents, plasticizers thiab lubricants. Cov txheej txheem ntawm no acid yog siv rau qhov siv thiab ua taws tswm ciab.

2. Calcium palmitate yog siv raws li ib feem ntawm compositions rau kev tiv thaiv tiv thaiv dej thiab dej (dej-repellency) ntawm daim tawv nqaij, ntau yam fabrics, ntoo, uas tsis yog-pob tshab tshuaj pleev ib ce thiab pleev.

3. Tsis tas li ntawd, sodium palmitate thiab siv raws li feem (a thickener) ntawm chav dej thiab tsev neeg soaps emulsifier muaj kom hniav zoo nkauj npaj.

4. Qhov yuav tsum tau rau methyl palmitate palmitic acid thiab ib co ntawm nws cov derivatives, hexadecanol. Tsis tas li ntawd, qhov no tshuaj yog siv raws li flavoring cov khoom siv rau foodstuffs.

5. Yav tas los ua ntsev hexadecanoic acid siv rau zus tau tej cov kws thaj ua rau thaj.