Cellulosic ethanol

Cellulosic ethanol bụ ethanol (ethyl mmanya) nke sitere na cellulose (eriri eriri nke osisi) karịa site na mkpụrụ osisi ma ọ bụ mkpụrụ osisi. Enwere ike imepụta ya site na ahịhịa, osisi, algae, ma ọ bụ osisi ndị ọzọ. A na-ekwukarị maka iji ya dị ka mmanụ mmanụ. Carbon dioxide nke ihe ọkụkụ na-amịkọrọ ka ha na-etolite na-ewepụ ụfọdụ n’ime carbon dioxide na-apụta mgbe ethanol nke sitere na ha na-agba ọkụ, ya mere mmanụ cellulosic ethanol nwere ikike inwe akara ụkwụ carbon dị ala karịa mmanụ ọkụ.

Mmasị e nwere na ethanol cellulosic bụ ikike ọ nwere iji dochie ethanol nke sitere na ọka ma ọ bụ okpete. Ebe ọ bụ na a na-ejikwa osisi ndị a na-emepụta ihe oriri, ịtụgharị ha maka mmepụta ethanol nwere ike ime ka ọnụ ahịa nri na-ebili; N'aka nke ọzọ, isi mmalite nke cellulose, n'ozuzu adịghị mpi nri, ebe ọ bụ na akụkụ fibrous nke osisi na-abụkarị ndị mmadụ anaghị eri ya. Uru ọzọ nwere ike ime bụ nnukwu ụdị dị iche iche na ụba nke isi mmalite cellulose; A na-ahụ ahịhịa, osisi na algae n'ihe fọrọ nke nta ka ọ bụrụ ebe ọ bụla dị n'ụwa. Ọbụna ihe mkpofu siri ike nke ime obodo dị ka akwụkwọ nwere ike ime ka ọ bụrụ ethanol. Isi ihe na-adịghị mma nke ethanol cellulosic ugbu a bụ ọnụ ahịa mmepụta ya dị elu, nke dị mgbagwoju anya ma na-achọ usoro ndị ọzọ karịa ethanol nke dabeere na ọka ma ọ bụ okpete.

Ethanol cellulosic nwetara nlebara anya dị ukwuu na 2000s na mmalite 2010s. Gọọmenti United States kacha nyere ego nyocha n'ime azụmahịa ya wee debe ebumnuche maka oke ethanol cellulosic agbakwunyere na mmanụ ụgbọala. Ọnụ ọgụgụ dị ukwuu nke ụlọ ọrụ ọhụrụ ọkachamara na cellulosic ethanol, na mgbakwunye na ọtụtụ ụlọ ọrụ dị ugbu a, tinyere ego na-emepụta ihe ọkụkụ. Otú ọ dị, mmepụta ethanol dabeere na ọka dị ọnụ ala karị, yana ọnụ ala mmanụ dị na 2010, pụtara na cellulosic ethanol adịghị asọmpi na mmanụ ọkụ ndị a kwadoro. N'ihi ya, ọtụtụ n'ime ndị ọhụrụ refineries e mechiri n'etiti 2010s na ọtụtụ n'ime ndị ọhụrụ tọrọ ntọala ghọrọ ihe efu. Ole na ole ka dị, mana a na-ejikarị eme ihe ngosi ma ọ bụ ebumnuche nyocha; Dị ka nke 2021, ọ dịghị onye na-emepụta ethanol cellulosic n'ọtụtụ.

## Nchịkọta
Cellulosic ethanol bụ ụdị biofuel emepụtara site na lignocellulose, ihe eji arụ ọrụ nke nwere ọtụtụ n'ime oke osisi ma mejupụtara ya bụ cellulose, hemicellulose na lignin. Ebe ndị a ma ama nke lignocellulose gụnyere ma ngwaahịa mkpofu ọrụ ugbo (dịka stovu ọka ma ọ bụ ibe osisi) na ahịhịa dị ka switchgrass na ụdị miscanthus. Akụrụngwa ndị a maka mmepụta ethanol nwere uru nke ịba ụba ma dị iche iche na ha agaghị mpi mmepụta nri, n'adịghị ka ọka na okpete ndị a na-ejikarị eme ihe. Agbanyeghị, ha na-achọkwa nhazi karịa iji mee ka monomers shuga dị na microorganisms a na-ejikarị emepụta ethanol site na gbaa ụka, nke na-ebuli ọnụ ahịa ethanol sitere na cellulos.

Cellulosic ethanol nwere ike ibelata ikuku griin haus site na 85% karịa mmanụ ụgbọala emezigharịrị. N'ụzọ dị iche, starch ethanol (dịka, site na ọka), nke na-ejikarị gas sitere n'okike na-enye ume maka usoro ahụ, nwere ike ọ gaghị ebelata ikuku gas na-ekpo ọkụ ma ọlị dabere n'otú e si emepụta nri nri starch. Dabere na National Academy of Sciences na 2011, ọ nweghị ihe nrụpụta bio-refinery dị adị maka ịtụgharị lignocellulosic biomass ka ọ bụrụ mmanụ ọkụ. Enweghị mmepụta nke cellulosic ethanol n'ogo nke iwu chọrọ bụ ihe ndabere nke Ụlọikpe Mkpegharị Mkpegharị nke United States maka District nke Columbia mara ọkwa January 25, 2013, na-emebi ihe a chọrọ n'aka ndị na-emepụta mmanụ ụgbọala na ụgbọala na United States site na. Ụlọ ọrụ nchekwa gburugburu ebe obibi chọrọ mgbakwunye nke cellulosic biofuels na ngwaahịa ha. Okwu ndị a, yana ọtụtụ ihe ịma aka mmepụta ihe ndị ọzọ siri ike, mere ka ndị nchọpụta amụma Mahadum George Washington kwupụta na "n'oge dị mkpirikpi, [cellulosic] ethanol enweghị ike izute nchekwa ike na ihe mgbaru ọsọ gburugburu ebe obibi nke mmanụ ụgbọala ọzọ."

## Akụkọ ihe mere eme
Onye French chemist, Henri Braconnot, bụ onye mbụ chọpụtara na cellulose nwere ike ime ka mmiri ghọọ shuga site na iji sulfuric acid na 1819. A pụkwara ịhazi sugar hydrolyzed ka ọ ghọọ ethanol site na gbaa ụka. Emepụta ethanol mbụ a na-ere ahịa malitere na Germany na 1898, bụ́ ebe a na-eji acid mee ka cellulose hydrolyze. Na United States, Standard Alcohol Company meghere ụlọ ọrụ mmepụta ethanol cellulosic mbụ na South Carolina na 1910. Mgbe e mesịrị, e meghere ụlọ ọrụ nke abụọ na Louisiana. Otú ọ dị, e mechiri osisi abụọ ahụ mgbe Agha Ụwa Mbụ gasịrị n'ihi ihe kpatara akụ na ụba.

Mgbalị mbụ nke ịzụ ahịa usoro maka ethanol sitere na osisi ka emere na Germany na 1898. Ọ gụnyere iji acid dilute hydrolyze cellulose na glucose, ma nwee ike iwepụta 7.6 lita ethanol kwa 100 kg nke ahịhịa osisi (18 US gal (68 L) kwa ton). N'oge na-adịghị anya ndị Jamanị mepụtara usoro mmepụta ihe ahaziri maka mpụta ihe ruru galọn US 50 (190 L) kwa tọn biomass. N'oge na-adịghị anya, usoro a chọtara ụzọ ya na United States, na-ejedebe na ụlọ ọrụ azụmahịa abụọ na-arụ ọrụ na ndịda ọwụwa anyanwụ n'oge Agha Ụwa Mbụ. Osisi ndị a na-eji ihe a na-akpọ "Usoro America" - otu akụkụ nke sulfuric acid hydrolysis. Ọ bụ ezie na ihe ndị a amịpụtara bụ ọkara nke usoro German mbụ (galọn US 25 (95 L) nke ethanol kwa ton na 50), ntinye nke usoro America dị elu karịa. Mbelata mmepụta osisi na-amanye ihe ọkụkụ ndị ahụ imechi obere oge ka njedebe nke Agha Ụwa Mbụ gasịrị. Ka ọ dị ugbu a, ntakịrị nyocha nke na-agbanwe agbanwe na dilute acid hydrolysis gara n'ihu na Laboratory USFS's Forest Products. N'oge Agha Ụwa nke Abụọ, US tụgharịrị ọzọ na cellulosic ethanol, oge a maka ntụgharị na butadiene iji mepụta roba sịntetik. Enyere ụlọ ọrụ Vulcan Copper na Supply nkwekọrịta ịrụ na ịrụ ọrụ osisi iji gbanwee sawdust ka ọ bụrụ ethanol. Ihe ọkụkụ a dabere na ngbanwe na usoro izizi German Scholler dịka ụlọ nyocha nke Forest Products Laboratory mepụtara. Osisi a nwetara mkpụrụ ethanol nke 50 US gal (190 L) kwa ton kpọrọ nkụ, mana ọ kaghị uru ma mechie ya mgbe agha ahụ gasịrị.

Site na mmepe ngwa ngwa nke teknụzụ enzyme n'ime afọ iri abụọ gara aga, usoro acid hydrolysis ejiriwo enzymatic hydrolysis dochie ya nke nta nke nta. Kemịkalụ pretreatment nke feedstock a chọrọ ka hydrolyze (iche iche) hemicellulose, n'ihi ya, ọ nwere ike na-arụ ọrụ nke ọma ghọọ sugars. A na-emepụta pretreatment nke acid dilute dabere na ọrụ mbụ na acid hydrolysis nke osisi na Laboratory Products Forest USFS. N'oge na-adịbeghị anya, Laboratory Products Forest yana Mahadum Wisconsin – Madison mepụtara pretreatment sulfite iji merie recalcitrance nke lignocellulose maka enzymatic hydrolysis siri ike nke cellulose osisi.

N'okwu 2007 State of the Union na Jenụwarị 23, 2007, Onye isi ala US George W. Bush kwupụtara ikike echere maka galọn US ijeri 35 (130×109 L) nke ethanol n'afọ 2017. Mgbe afọ ahụ gasịrị, Ngalaba Ike US nyere onyinye. $385 nde na onyinye ezubere iji malite mmepụta ethanol na-awụlikwa elu site na isi mmalite ndị na-abụghị omenala dị ka ibe osisi, switchgrass, na peels citrus.

## Ụzọ e si emepụta ya
áká_ịkẹngạ|thumb|Bioreactor maka nyocha cellulosic ethanol.
Usoro iji mepụta ethanol site na iji usoro ndu bụ:

# Usoro "pretreatment" iji mee ka ihe lignocellulosic dị ka osisi ma ọ bụ ahịhịa na-eme ka hydrolysis nwee ike.
# Cellulose hydrolysis (cellulolysis) iji gbarie ụmụ irighiri ihe n'ime shuga
# Microbial gbaa ụka nke shuga ngwọta
# Distillation na akpịrị ịkpọ nkụ iji mepụta mmanya dị ọcha

N'afọ 2010, e mepụtara ụdị yist sitere na mkpụrụ ndụ ihe nketa iji mepụta enzymes na-agbari cellulose nke ya. N'ịbụ ndị na-eche na nkà na ụzụ a nwere ike ịba ụba na ọkwa mmepụta ihe, ọ ga-ewepụ otu usoro ma ọ bụ karịa nke cellulolysis, na-ebelata ma oge achọrọ na ọnụ ahịa nke mmepụta.

Ọ bụ ezie na lignocellulose bụ akụ ihe ọkụkụ kachasị ukwuu, a na-ebelata ojiji ya site na nhazi ya siri ike. N'ihi ya, a na-achọ ọgwụgwọ dị irè iji tọhapụ cellulose site na lignin seal na usoro crystalline ya iji mee ka ọ nweta ya maka nzọụkwụ hydrolysis na-esote. Ka ọ dị ugbu a, a na-eme ọtụtụ ọgwụgwọ mbụ site n'ụzọ anụ ahụ ma ọ bụ kemịkal. Iji nweta arụmọrụ dị elu, a chọrọ ọgwụgwọ anụ ahụ na nke kemịkal. Pretreatment anụ ahụ na-agụnye ibelata urughuru biomass site n'ibu nhazi ụzọ dị ka egwe ọka ma ọ bụ extrusion. Ngwọta kemịkalụ na-ebelata akụkụ nke lignocellulose ka enzymes wee nweta cellulose maka mmeghachi omume microbial.

Usoro pretreatment kemịkalụ gụnyere acid hydrolysis, uzuoku mgbawa, amonia fiber mgbasa, organosolv, sulfite pretreatment, SO2-ethanol-water fractionation, alkaline wet oxidation na ozone pretreatment. E wezụga ntọhapụ cellulose dị irè, ọgwụgwọ dị mma kwesịrị ibelata mmepụta nke ngwaahịa mmebi n'ihi na ha nwere ike igbochi usoro hydrolysis na gbaa ụka. Ọnụnọ nke ndị na-eme ihe na-eme ka ọ dịkwuo mgbagwoju anya ma na-abawanye ọnụ ahịa nke mmepụta ethanol n'ihi usoro nkwụsị nke achọrọ. Dịka ọmụmaatụ, n'agbanyeghị na acid hydrolysis bụ usoro ọgwụgwọ izizi kacha ochie na nke amụrụ, ọ na-emepụta ọtụtụ ihe mgbochi nwere ike gụnyere furfural na hydroxymethylfurfural. Amonia Fiber Expansion (AFEX) bụ ihe atụ nke pretreatment na-ekwe nkwa nke na-emepụta dịghị inhibitors.

Ọtụtụ usoro ọgwụgwọ mbụ adịghị arụ ọrụ mgbe etinyere ya na nri nri nwere ọdịnaya lignin dị elu, dị ka biomass ọhịa. Ndị a chọrọ ụzọ ọzọ ma ọ bụ pụrụ iche. Organosolv, SPORL ('Sulfite pretreatment iji merie recalcitrance nke lignocellulose') na SO2-ethanol-water (AVAP®) usoro bụ atọ usoro nwere ike nweta n'elu 90% cellulose ntughari maka ọhịa biomass, karịsịa ndị softwood ụdị. SPORL bụ ihe kacha arụ ọrụ ike (mmepụta shuga kwa nkeji ike oriri na pretreatment) yana usoro siri ike maka pretreatment nke biomass ọhịa nwere obere mmepụta nke ihe mgbochi gbaa ụka. Organosolv pulping dị irè karịsịa maka osisi siri ike ma na-enye mgbake dị mfe nke ngwaahịa hydrophobic lignin site na dilution na ọdịda. e ji arụ ọrụ mgbake nke chemicals.

### Usoro cellulolytic
Hydrolysis nke cellulose (cellulolysis) na-emepụta shuga dị mfe nke nwere ike ịgbanye n'ime mmanya. Enwere usoro cellulolysis isi abụọ: usoro kemịkalụ iji acid, ma ọ bụ mmeghachi omume enzymatic site na iji cellulases.

#### Hydrolysis nke kemịkal
N'ime usoro ọdịnala ndị e mepụtara na narị afọ nke 19 na mmalite nke narị afọ nke 20, a na-eme hydrolysis site na iji acid wakpo cellulose. Enwere ike iji acid dilute n'okpuru oke okpomọkụ na nrụgide dị elu, ma ọ bụ acid nwere ike tinyekwuo nwere ike iji na okpomọkụ dị ala na nrụgide ikuku. Ngwakọta cellulosic nke acid na sugars decrystallized na-emeghachi omume n'ihu mmiri iji mechaa mkpụrụ ndụ shuga n'otu n'otu (hydrolysis). Ngwaahịa sitere na hydrolysis a na-ewepụsị ya, a na-eji gbaa ụka yist emepụta ethanol. Dị ka e kwuru, ihe mgbochi dị ịrịba ama na usoro itughari acid bụ na hydrolysis dị oke ike nke na a na-emepụta ihe ndị na-emebi ihe na-egbu egbu nke nwere ike igbochi gbaa ụka. BlueFire Renewables na-eji acid concentrated n'ihi na ọ naghị emepụta ihe fọrọ nke nta ka ọ bụrụ ọtụtụ ndị na-egbochi gbaa ụka, mana a ga-ekewapụ ya na mmiri shuga maka recycle [nkewa akwa chromatographic nke na-emegharị emegharị, dịka ọmụmaatụ] ka ọ mara mma n'ahịa.

Ndị ọkà mmụta sayensị na-ahụ maka ọrụ nyocha ọrụ ugbo chọpụtara na ha nwere ike ịnweta ma gbaa ihe fọrọ nke nta ka ọ bụrụ shuga niile fọdụrụ na ahịhịa ọka. Ndị shuga dị na mgbidi cell nke osisi ahụ, bụ nke a ma ama na ọ siri ike ịkụda. Iji nweta shuga ndị a, ndị ọkà mmụta sayensị na-eji alkaline peroxide dozie ahịhịa ọka wit, wee jiri enzymes pụrụ iche kwatuo mgbidi cell. Usoro a weputara galọn US 93 (350 L) nke ethanol kwa tọn ahịhịa ọka.

#### Hydrolysis nke enzymes
Enwere ike ịgbaji agbụ cellulose n'ime mkpụrụ ndụ glucose site na enzymes cellulase. Mmeghachi omume a na-eme na okpomọkụ nke ahụ dị n'ime afọ nke anụ anụ dị ka ehi na atụrụ, bụ ebe ụmụ nje na-emepụta enzymes. Usoro a na-eji ọtụtụ enzymes na ọkwa dị iche iche nke ntụgharị a. N'iji usoro enzymatic yiri nke ahụ, ihe lignocellulosic nwere ike iji enzymaticly mee ihe n'ọnọdụ dịtụ nro (50 ° C na pH 5), si otú a na-eme ka cellulose dị irè na-agbaji na-enweghị nguzobe nke ngwaahịa ndị ga-egbochi ọrụ enzyme. Ụzọ ọgwụgwọ niile bụ isi, gụnyere acid dilute, chọrọ usoro enzymatic hydrolysis iji nweta mkpụrụ shuga dị elu maka ịgba ụka ethanol.

Enwere ike iji enzymes fungal mee ka cellulose hydrolyze. Akụrụngwa (mgbe osisi ma ọ bụ ahịhịa) ka ga-ebu ụzọ gwọọ ya iji mee ka ọ dị mma na hydrolysis. N'afọ 2005, ụlọ ọrụ Iogen kwupụtara na ọ na-eji ero Trichoderma reesei na-emepụta usoro iji zoo "enzyme ndị emepụtara pụrụ iche" maka usoro enzymatic hydrolysis.

Ụlọ ọrụ Canada ọzọ, SunOpta, na-eji pretreatment mgbawa uzuoku, na-enye nkà na ụzụ ya na Verenium (nke bụbu Celunol Corporation) na Jennings, Louisiana, ụlọ ọrụ Abengoa na Salamanca, Spain, na China Resources Alcohol Corporation na Zhaodong. Ebe nrụpụta CRAC na-eji stovu ọka dị ka akụrụngwa.

### Mgbasa nke nje
 
Dị ka o si dị, yist na-eme bred (Saccharomyces cerevisiae), adịla anya n'ụlọ ọrụ ebe a na-emepụta mmanya na-emepụta ethanol sitere na hexoses (sugar carbon isii). N'ihi ọdịdị dị mgbagwoju anya nke carbohydrates dị na lignocellulosic biomass, nnukwu xylose na arabinose (sugar carbon ise sitere na akụkụ hemicellulose nke lignocellulose) dịkwa na hydrolysate. Dịka ọmụmaatụ, na hydrolyzate nke ọka ọka, ihe dịka 30% nke ngụkọta shuga na-agba agba bụ xylose. N'ihi ya, ikike nke microorganisms na-agba agba iji jiri ụdị shuga niile dị na hydrolyzate dị mkpa iji mee ka asọmpi akụ na ụba nke cellulosic ethanol na protein ndị nwere ike na-emepụta ihe.

N'ime afọ ndị na-adịbeghị anya, injinia metabolic maka microorganisms ejiri na-emepụta ethanol mmanụ egosila ọganihu dị ukwuu. E wezụga Saccharomyces cerevisiae, microorganisms dị ka Zymomonas mobilis na Escherichia coli ka ezubere iche site na injinịa metabolic maka mmepụta ethanol cellulosic. Ihe na-adọrọ adọrọ n'akụkụ akụkụ ahụ mgbakasị ọzọ bụ ike ya ịgbasa shuga carbon ise na-eme ka mkpụrụ nke ngwaahịa nri dịkwuo mma. A na-ahụkarị ikike a n'ime ihe ndị sitere na nje bacteria. [Ihe ndekọ achọrọ]

N'oge na-adịbeghị anya, a kọwapụtara yist ndị emepụtara nke ọma na-agbakọ xylose, na arabinose, na ọbụna ha abụọ ọnụ. Mkpụrụ ndụ yist na-adọrọ mmasị karịsịa maka usoro ethanol cellulosic n'ihi na ejirila ha na nkà na ụzụ biotechnology ruo ọtụtụ narị afọ, na-anabata ethanol dị elu na ntinye ihe mgbochi ma nwee ike itolite na obere pH ụkpụrụ iji belata mmetọ nje.

### Ngwakọta hydrolysis na fermentation
A hụla ụfọdụ ụdị nje bacteria nwere ike ịtụgharị mkpụrụ okwu cellulose ka ọ bụrụ ethanol. Otu ihe atụ bụ Clostridium thermocellum, bụ́ nke na-eji cellulosome dị mgbagwoju anya gbarie cellulose na synthesize ethanol. Agbanyeghị, C. thermocelum na-emepụtakwa ngwaahịa ndị ọzọ n'oge metabolism cellulose, gụnyere acetate na lactate, na mgbakwunye na ethanol, na-ebelata arụmọrụ nke usoro ahụ. A na-atụkwa ụfọdụ mbọ nyocha iji kwalite mmepụta ethanol site na nje bacteria injinia mkpụrụ ndụ ihe nketa na-elekwasị anya n'okporo ụzọ na-emepụta ethanol.

### Usoro gas (ụzọ okpomọkụ)
[thumb|200x200px|Mmiri na-agbanye n'àkwà na Güssing Burgenland [Austria]]
Usoro gasification anaghị adabere na kemịkalụ kemịkalụ nke cellulose yinye (cellulolysis). Kama ịgbaji cellulose n'ime ụmụ irighiri shuga, a na-eme ka carbon dị n'ihe ndị dị n'ime ya ghọọ gas na-emepụta ihe, na-eji ihe ruru ọkụ ọkụ. Enwere ike inye carbon monoxide, carbon dioxide na hydrogen ka ọ bụrụ ụdị fermenter pụrụ iche. Kama ịgbakọ sugar na yist, usoro a na-eji nje bacteria Clostridium ljungdahlii. Ihe microorganism a ga-etinye carbon monoxide, carbon dioxide na hydrogen ma mepụta ethanol na mmiri. Ya mere enwere ike imebi usoro a ụzọ atọ:

# Gasification - A na-agbajikwa molekul gbagọrọ agbagọ nke carbon iji nweta carbon dị ka carbon monoxide, carbon dioxide na hydrogen.
# Fermentation - Tugharia carbon monoxide, carbon dioxide na hydrogen ka ọ bụrụ ethanol site na iji organism Clostridium ljungdahlii.
# Distillation - Ethanol kewapụrụ na mmiri

Nnyocha e mere n'oge na-adịbeghị anya achọpụtala nje bacteria Clostridium ọzọ nke yiri ka ọ na-arụ ọrụ nke ọma ugboro abụọ n'ịme ethanol sitere na carbon monoxide dị ka nke a kpọtụrụ aha n'elu.

N'aka nke ọzọ, a na-enyefe gas na-emepụta gas site na gasification na reactor catalytic ebe a na-eji emepụta ethanol na mmanya ndị ọzọ dị elu site na usoro thermochemical. Usoro a nwekwara ike ịmepụta ụdị mmanụ ọkụ ndị ọzọ, echiche ọzọ nke ụlọ ọrụ Montreal Enerkem gosipụtara nke ọma n'ụlọ ọrụ ha na Westbury, Quebec.

## Hemicellulose na ethanol
A na-eme nnyocha siri ike iji zụlite ụzọ akụ na ụba iji gbanwee ma cellulose na hemicellulose na ethanol. Fermentation nke glucose, bụ isi ngwaahịa nke cellulose hydrolyzate, na ethanol bụ usoro emebelarị ma rụọ ọrụ nke ọma. Agbanyeghị, ntughari nke xylose, shuga pentose nke hemicellulose hydrolyzate, bụ ihe na-egbochi ya, ọkachasị na ọnụnọ glucose. Ọzọkwa, a pụghị ileghara ya anya dị ka hemicellulose ga-eme ka arụmọrụ na ọnụ ahịa nke mmepụta ethanol cellulosic dịkwuo elu.

Sakamoto (2012) et al. gosi ike nke mkpụrụ ndụ ihe nketa injinia iji gosipụta enzymes hemicellulase. Ndị nchọpụta ahụ mepụtara ụdị Saccharomyces cerevisiae recombinant nke nwere ike:

# hydrolyze hemicellulase site na codeisplaying endoxylanase n'elu cell ya,
# assimilate xylose site na ngosipụta nke xylose reductase na xylitol dehydrogenase.

Ahụhụ ahụ nwere ike ịtụgharị ahịhịa ahịhịa osikapa ka ọ bụrụ ethanol, nke nwere akụkụ hemicellulosic. Ọzọkwa, ọ na-enwe ike ịmepụta 2.5x ọzọ ethanol karịa njikwa njikwa, na-egosi usoro dị irè nke elu cell-engineering na-emepụta ethanol.

## Uru ya

### Uru ndị ethanol na-arụ n'ozuzu ha
Ethanol na-ere ọkụ nke ọma na nke ọma karịa mmanụ ụgbọala. N'ihi na osisi na-eri carbon dioxide ka ha na-etolite, bioethanol nwere akara ukwu carbon dị ala karịa mmanụ ọkụ. Ịgbanwe ethanol maka mmanụ nwekwara ike ibelata ndabere obodo na mbubata mmanụ.

### Uru nke cellulosic ethanol karịa ọka ma ọ bụ ethanol sitere na shuga

Mmepụta ethanol cellulosic nke a na-ere n'ahịa, nke n'adịghị ka ọka na okpete agaghị mpi mmepụta nri, ga-adọrọ mmasị nke ukwuu ebe ọ ga-ebelata nrụgide a na-enwe n'ubi nri ndị a.

Ọ bụ ezie na ọnụ ahịa nhazi ya dị elu, ọnụahịa cellulose biomass dị ọnụ ala karịa nke ọka ma ọ bụ mkpụrụ osisi. Ọzọkwa, ebe ọ bụ na cellulose bụ isi ihe na-emepụta ihe ọkụkụ, a pụrụ iweta ihe ọkụkụ ahụ dum, ọ bụghị nanị mkpụrụ osisi ma ọ bụ mkpụrụ osisi. Nke a na-ebute mkpụrụ kacha mma; dịka ọmụmaatụ, switchgrass na-amịpụta ethanol okpukpu abụọ karịa ọka. Ihe biomass maka mmepụta cellulose chọrọ ntinye ole na ole, dị ka fatịlaịza, ahịhịa ahịhịa, na mgbọrọgwụ ha buru ibu na-eme ka mma ala dị mma, belata mbuze, ma na-abawanye njide na-edozi ahụ. Mgbasa ụkwụ carbon zuru ụwa ọnụ na ikike okpomoku zuru ụwa ọnụ nke ethanol cellulosic dị ala nke ukwuu (lee eserese) na ike ụgbụ a na-enweta dị elu ọtụtụ ugboro karịa nke ethanol dabere na ọka.

Ngwa akụrụngwa nwere ike hiri nne. Ihe dị ka 44% nke mkpofu ụlọ a na-emepụta n'ụwa niile bụ nri na elu. A na-atụfu ihe dị ka nde tọn 323 nke akụrụngwa nwere cellulose nke enwere ike iji mepụta ethanol kwa afọ na US naanị. Nke a gụnyere nde tọn 36.8 nke mkpofu nkụ n'obodo mepere emepe, nde tọn 90.5 nke ihe mkpofu ahịhịa, nde tọn 45 nke ahịhịa ahịhịa, na 150.7 nde tọn nkụ ọka na ahịhịa ọka. Ọzọkwa, a pụrụ iji ihe ọkụkụ na-emepụta cellulose kụọ ọbụna akụkụ ala maka ọrụ ugbo, nke na-ebute mmepụta zuru oke iji dochie anya mbubata mmanụ ugbu a na United States.

Akwụkwọ, kaadiboodu, na nkwakọ ngwaahịa nwere ihe dị ka 17% nke mkpofu ụlọ zuru ụwa ọnụ; ọ bụ ezie na a na-emegharị ụfọdụ n'ime ihe ndị a. Dị ka ngwaahịa ndị a nwere cellulose, ha na-agbanwe ghọọ cellulosic ethanol, nke ga-ezere mmepụta nke methane, ikuku griin ha siri ike, n'oge ire ere.

## Ọghọm ya

### Ọghọm ndị ọzọ
Isi ihe ndọghachi azụ nke mmanụ ethanol bụ akụ na ụba mmanụ ala ya dị ala ma e jiri ya tụnyere mmanụ ụgbọala mgbe ị na-eji ethanol n'ime injin emebere maka mmanụ ụgbọala nwere oke mkpakọ dị ala.

### Ọghọm nke cellulosic ethanol karịa ọka ma ọ bụ ethanol sitere na shuga
Ihe kachasị njọ nke ethanol cellulosic bụ ọnụ ahịa dị elu na mgbagwoju anya nke mmepụta ya, bụ nke bụ isi ihe na-egbochi azụmahịa ya.

## Ọnọdụ akụ na ụba
Ọ bụ ezie na ahịa bioethanol zuru ụwa ọnụ nwere oke (ihe dị ka ijeri lita 110 na 2019), ihe ka ukwuu bụ sitere na ọka ma ọ bụ okpete, ọ bụghị cellulose. N'afọ 2007, a na-eme atụmatụ ọnụ ahịa mmepụta ethanol site na isi mmalite cellulosic ca. USD 2.65 kwa galọn (€0.58 kwa lita), nke dị ihe dị ka ugboro 2–3 dị ọnụ karịa ethanol nke sitere na ọka. Agbanyeghị, ahịa ethanol cellulosic ka dị obere ma dabere na enyemaka gọọmentị. Gọọmenti US bu ụzọ debere ebumnuche cellulosic ethanol nke nta nke nta na-agbago site na ijeri lita 1 na 2011 ruo ijeri lita 60 na 2022. Agbanyeghị, ihe mgbaru ọsọ ndị a kwa afọ fọrọ nke nta ka ọ bụrụ mgbe niile ka ewepụrụ ya mgbe ọ bịara doo anya na enweghị ohere izute ha. Ọtụtụ n'ime osisi ndị na-emepụta ethanol cellulosic kagburu ma ọ bụ gbahapụrụ na mmalite 2010s. Osisi ndị DuPont, General Motors na BP wuru ma ọ bụ kwadoro ya, n'etiti ọtụtụ ndị ọzọ, mechiri ma ọ bụ ree ya. Dị ka nke 2018, ọ bụ naanị otu nnukwu osisi fọdụrụ na US.

Ka e wee too ya na nnukwu mmepụta, cellulose biomass aghaghị ịsọ mpi n'iji ala ubi a na-eme ihe, karịsịa maka mmepụta ihe ọkụkụ. N'ime ijeri acres 2.26 nke United States (nde 9.1 km2) nke ala enweghị mmiri, 33% bụ oke ọhịa, 26% ala ịta ahịhịa na ahịhịa, na 20% ala ihe ọkụkụ. Nnyocha nke Ngalaba Maka Ike na Ọrụ Ugbo nke U.S. na 2005 tụrụ aro na 1.3 ijeri tọn nkụ nke biomass dị maka iji ethanol eme ihe ma na-ejigide mmetụta a na-anakwere na ọhịa, ọrụ ugbo.

### Ntụnyere ya na ethanol sitere na ọka
Ka ọ dị ugbu a, cellulose na-esi ike ma dị ọnụ karịa ịhazi n'ime ethanol karịa ọka ma ọ bụ okpete. Ngalaba ike nke United States mere atụmatụ na 2007 na ọ na-efu ihe dịka $2.20 kwa galọn iji mepụta ethanol cellulosic, nke bụ 2-3 ugboro karịa ethanol sitere na ọka. Enzymes nke na-emebi mgbidi cell cell na-eri US $ 0.40 kwa galọn ethanol ma e jiri ya tụnyere US $ 0.03 maka ọka. Otú ọ dị, cellulosic biomass dị ọnụ ala karịa ọka, n'ihi na ọ na-achọ ntinye ole na ole, dị ka ume, fatịlaịza, ahịhịa ahịhịa, na-esonyere ya na obere mbuze nke ala na mma ala ọmụmụ. Na mgbakwunye, ihe siri ike na-adịghị agba agba na enweghị ntụgharị nke fọdụrụ mgbe emechara ethanol nwere ike ịgba ọkụ iji nye mmanụ ọkụ dị mkpa iji rụọ ọrụ ngbanwe ma mepụta ọkụ eletrik. Ike a na-eji na-arụ ọrụ ethanol sitere na ọka sitere na coal na gas. Ụlọ ọrụ maka ịdabere na onwe onye na mpaghara na-eme atụmatụ ọnụahịa cellulosic ethanol sitere na ọgbọ mbụ nke osisi azụmahịa ga-adị na $ 1.90- $ 2.25 kwa galọn, ewezuga ihe mkpali. Nke a tụlere ọnụ ahịa ugbu a bụ $1.20–$1.50 kwa galọn maka ethanol sitere na ọka yana ọnụ ahịa mkpọsa ugbu a karịrị $4.00 kwa galọn maka mmanụ ụgbọala mgbe niile (nke a na-enye nkwado na ụtụ).

### Ihe mgbochi nke ọnụ ahịa enzyme
Cellulases na hemicellulases eji na mmepụta nke cellulosic ethanol dị ọnụ karịa ndị ọgbọ mbụ ha. Enzymes achọrọ maka mmepụta ethanol ọka ọka na-efu 2.64-5.28 US dollar kwa cubic mita nke ethanol emepụtara. Enzymes maka mmepụta ethanol cellulosic na-atụ anya na ọ ga-efu 79.25 US dollar, nke pụtara na ha dị okpukpu 20-40 karịa ọnụ. A na-ekwu na ọnụ ahịa dị iche na ọnụọgụ achọrọ. Ezinụlọ cellulase nke enzymes nwere usoro nke otu ma ọ bụ abụọ n'usoro pere mpe nke arụmọrụ. Ya mere, ọ na-achọ 40 ruo 100 ugboro karịa nke enzyme ka ọ dị na mmepụta ya. Maka tọn nke ọ bụla biomass ọ chọrọ 15-25 kilogram nke enzyme. Atụmatụ ndị na-adịbeghị anya dị ala, na-atụ aro 1 kg nke enzyme kwa tọn kpọrọ nkụ nke nri nri biomass. Enwekwara ọnụ ahịa isi obodo dị elu jikọtara ya na ogologo oge nnabata maka ụgbọ mmiri na-arụ ọrụ hydrolysis enzymatic. N'ozuzu, enzymes nwere akụkụ dị ịrịba ama nke 20-40% maka mmepụta ethanol cellulosic. Otu akwụkwọ na-adịbeghị anya na-eme atụmatụ na nsonye dị na 13-36% nke ọnụ ahịa ego, na isi ihe bụ otú e si emepụta enzyme cellulase. Maka cellulase emepụtara na mpụga, mmepụta enzyme ruru 36% nke ọnụ ahịa ego. Maka enzyme emepụtara na saịtị na osisi dị iche, akụkụ ya bụ 29%; Maka mmepụta enzyme agbakwunyere, akụkụ ya bụ 13%. Otu n'ime uru ndị bụ isi nke mmepụta agbakwunyere bụ na biomass kama glucose bụ usoro uto enzyme. Biomass na-efu obere ego, ọ na-eme ka ethanol cellulosic na-esi na ya pụta bụrụ 100% biofuel nke abụọ, ya bụ, ọ dịghị eji 'nri maka mmanụ'.

## Nri nri
N'ozuzu, e nwere ụdị nri nri abụọ: ọhịa (osisi) biomass na biomass ugbo. Na US, ihe dị ka ijeri tọn 1.4 akọrọ nke biomass ka enwere ike imepụta nke ọma kwa afọ. Ihe dị ka nde tọn 370 ma ọ bụ 30% bụ biomass nke ọhịa. Ohia biomass nwere cellulose na lignin dị elu yana ọdịnaya hemicellulose na ntụ dị ala karịa biomass ugbo. N'ihi ihe isi ike na mkpụrụ ethanol dị ala na fermenting pretreatment hydrolysate, ọkachasị ndị nwere shuga dị elu 5 carbon hemicellulose dị ka xylose, biomass ọhịa nwere nnukwu uru karịa biomass ugbo. Biomass nke ọhịa nwekwara nnukwu njupụta nke na-ebelata ọnụ ahịa njem. Enwere ike iweta ya n'afọ nke na-ewepụ nchekwa ogologo oge. Ọdịnaya ntụ ntụ dị nso nke biomass nke ọhịa na-ebelata nke ọma ibu n'ime njem na nhazi. Iji gboo mkpa maka ihe dị iche iche dị iche iche, biomass nke ọhịa ga-abụ ngwakọta ihe oriri dị mkpa na-enye nri n'ime akụ na ụba biobased n'ọdịnihu. Otú ọ dị, biomass nke ọhịa na-atụgharị uche karịa biomass nke ugbo. N'oge na-adịbeghị anya, USDA Forest Products Laboratory yana Mahadum Wisconsin-Madison mepụtara teknụzụ dị mma nke nwere ike imeri ike recalcitrance nke ọhịa (osisi) biomass gụnyere nke ụdị softwood nwere obere xylan ọdịnaya. Omenala kpụ ọkụ n'ọnụ nke obere oge ma ọ bụ ọrụ ugbo osisi nwere ike inye ohere na-enweghị oke maka mmepụta biomass nke ọhịa.

Osisi osisi sitere na slashes na n'elu osisi wee hụ uzuzu sitere na igwe igwe, na akwụkwọ mkpofu bụ nri anụ ọhịa biomass maka mmepụta ethanol cellulosic.

Switchgrass (Panicum virgatum) bụ ahịhịa ahịhịa toro ogologo. Amara maka isi ike ya na uto ngwa ngwa, afọ a na-eto n'ime ọnwa ọkụ ruo n'ogo nke 2–6 ụkwụ. Enwere ike ito ahịhịa ahịhịa n'ọtụtụ akụkụ nke United States, gụnyere swampland, larịị, iyi, na n'akụkụ oke osimiri & okporo ụzọ interstate. Ọ bụ mkpụrụ nke onwe (ọ dịghị traktọ maka ịgha mkpụrụ, naanị maka ịgha mkpụrụ), na-eguzogide ọtụtụ ọrịa na pests, ma nwee ike ịmepụta mkpụrụ dị elu na ngwa ngwa nke fatịlaịza na kemịkalụ ndị ọzọ. Ọ na-anabatakwa ala dara ogbenye, idei mmiri, & ụkọ mmiri ozuzo; na-eme ka mma ala dị mma ma na-egbochi mbuze n'ihi ụdị mgbọrọgwụ ya.

Switchgrass bụ ihe mkpuchi akwadoro maka ala echedoro n'okpuru Mmemme Nchekwa Federal (CRP). CRP bụ mmemme gọọmentị na-akwụ ndị na-emepụta ego ụgwọ maka emeghị ihe ọkụkụ n'ala nke ihe ọkụkụ toro na nso nso a. Usoro a na-ebelata mbuze nke ala, na-eme ka mmiri dịkwuo mma, na-abawanye ebe obibi anụ ọhịa. Ala CRP na-eje ozi dị ka ebe obibi maka egwuregwu ugwu, dị ka pheasants na ọbọgwụ, na ọtụtụ ụmụ ahụhụ. A tụlere Switchgrass maka mmepụta biofuel maka ojiji na ala Mmemme Nchekwa Nchekwa (CRP), nke nwere ike ịbawanye nkwado gburugburu ebe obibi wee belata ọnụ ahịa mmemme CRP. Agbanyeghị, iwu CRP ga-agbanwerịrị iji kwe ka ojiji akụ na ụba a nke ala CRP.

Miscanthus × giganteus bụ nri ọzọ bara uru maka mmepụta ethanol cellulosic. Ụdị ahihia a sitere na Eshia ma bụrụ ngwakọ na-adịghị mma nke Miscanthus sinensis na Miscanthus sacchariflorus. O nwere ihe ọkụkụ dị elu, ọ dị ọnụ ala itolite, ma na-eme nke ọma n'ụdị ihu igwe dị iche iche. Otú ọ dị, n'ihi na ọ na-adịghị ike, ọ na-achọkwa ịgbasa ahịhịa, na-eme ka ọ dịkwuo ọnụ.

Atụwo aro na Kudzu nwere ike bụrụ isi iyi bara uru nke biomass.

## Ahịa ethanol cellulosic
N'ịbụ nke e nwetara site na enyemaka na enyemaka, mmụba na nyocha ethanol cellulosic na osisi ndị na-anya ụgbọelu mere na mmalite 2000s. Ụlọ ọrụ ndị dị ka Iogen, POET, na Abengoa wuru ụlọ nrụpụta ndị nwere ike ịhazi biomass ma gbanwee ya ka ọ bụrụ ethanol, ebe ụlọ ọrụ dịka DuPont, Diversa, Novozymes, na Dyadic tinyere ego na nyocha enzyme. Agbanyeghị, ọtụtụ n'ime osisi ndị a kagburu ma ọ bụ mechie na mbido 2010 dịka ihe mgbochi teknụzụ siri ike imeri. Dị ka nke 2018, ọ bụ naanị otu cellulosic ethanol osisi ka nọgidere na-arụ ọrụ.

N'ime afọ 2010 gara aga, ụlọ ọrụ dị iche iche na-anwa oge ụfọdụ mgbalị dị nta n'ịzụ ahịa ethanol cellulosic, ọ bụ ezie na ọrụ ndị dị otú ahụ na-anọgide na-adị n'ọtụtụ nyocha ma na-adaberekarị na enyemaka. Ụlọ ọrụ Granbio, Raízen na Centro de Tecnologia Canavieira ọ bụla na-agba ọsọ a pilot-scale facility na-arụ ọrụ na Brazil, nke ọnụ na-emepụta gburugburu 30 nde lita na 2019. Iogen, nke malitere dị ka onye na-emepụta enzyme na 1991 wee maliteghachi onwe ya iji lekwasị anya na isi. na cellulosic ethanol na 2013, nwere ọtụtụ patent maka mmepụta ethanol cellulosic ma nye nkà na ụzụ maka osisi Raízen. Companieslọ ọrụ ndị ọzọ na-emepe emepe teknụzụ ethanol cellulosic dị ka nke 2021 bụ Inbicon (Denmark); Ụlọ ọrụ na-arụ ọrụ ma ọ bụ na-eme atụmatụ mmepụta ihe na-emepụta ụgbọelu gụnyere New Energy Blue (US), Sekab (Sweden) na Clariant (na Romania). Abengoa, ụlọ ọrụ Spen nwere akụ ethanol cellulosic, kwụsịrị na 2021.

Agencylọ ọrụ ume ọhụrụ nke Australia, yana gọọmentị steeti na ime obodo, nyere ego maka ụlọ ọrụ na-anya ụgbọ elu na 2017 na 2020 na New South Wales dịka akụkụ nke mbọ iji mee ka akụ na ụba mpaghara pụọ na mgbapụta kol.

### Nkwado Gọọmentị US
Site na 2006, gọọmentị etiti US malitere ịkwalite mmepe ethanol sitere na nri nri cellulosic. Na May 2008, Congress weputara ụgwọ ọrụ ugbo ọhụrụ nke nwere ego maka ịzụ ahịa nke biofuels ọgbọ nke abụọ, gụnyere cellulosic ethanol. Iwu nri, nchekwa, na ike nke 2008 nyere maka onyinye na-ekpuchi ihe ruru 30% nke ọnụ ahịa mmepe na iwulite ihe ngosi biorefineries maka imepụta "ihe ọkụkụ dị elu," nke gụnyere nke ọma mmanụ ọkụ niile esighị na starch ọka ọka. O kwekwara ka mbinye ego ruru nde $250 maka iwu ụlọ biorefineries nke azụmahịa.

Na Jenụwarị 2011, USDA kwadoro $405 nde na nkwa mbinye ego site na ụgwọ ọrụ Ugbo 2008 iji kwado azụmahịa nke ethanol cellulosic na ụlọ ọrụ atọ nke Coskata, Enerkem na INEOS New Planet BioEnergy nwere. Ọrụ ndị a na-anọchi anya mkpokọta 73 million US galọn (280,000 m3) ikike mmepụta kwa afọ ma ga-amalite imepụta ethanol cellulosic na 2012. USDA wepụtakwara ndepụta nke ndị na-emepụta biofuel dị elu bụ ndị ga-anata ụgwọ iji gbasaa mmepụta nke biofuels dị elu. Na Julaị 2011, Ngalaba Energy nke US nyere POET nde $105 na nkwa mbinye ego maka ụlọ ahịa nke a ga-ewu Emmetsburg, Iowa.

## Hụkwa


* Ọgbọ nke abụọ biofuels
* Nri vs. mmanụ

## Ihe odide
 

## Njikọ mpụga

* Ndepụta nke U.S. Ethanol Plants
* A na-eji teknụzụ dị iche iche eme ihe maka Cellulosic Ethanol Path
* Mgbanwe gaa n'Ọgbọ nke Abụọ Ethanol
* USDA & DOE Release National Biofuels Action Plan
* Ịzụ ahịa Cellulosic Ethanol
* Cellulosic ethanol mmepụta nwere ike "gbawaa"
* Onye na-ede uri na-emepụta Cellulosic Ethanol na Pilot Scale
* Nkwado ndị ọzọ nke US hụrụ na ọ ga-ekwe omume maka osisi ethanol
* Shell na-agbanye cellulosic ethanol push na Codexis ọhụrụ
* Enerkem iji wuo ụlọ ọrụ ethanol cellulosic na US
* Ethanol Production nwere ike iru 90 Billion Gallons site na 2030 nke Sandia National Laboratories na GM Corp kwadoro.
* Sandia National Laboratories & GM study: usoro PDF sitere na hitectransportation.org
* Mgbanwe ahịhịa Mmanụ na-emepụta Ike dị ukwuu.
* Ethanol Site na Cellulose: A General Review - P.C. Badger, 2002
* US DOEOffice nke Biological and Environmental Research (OBER).
* National Renewable Energy Laboratory, Research Advances - Cellulosic Ethanol.
* USDA Forest Products Laboratory E debere  Wayback Machine
* reuters.com, New biofuels ga-abịa site n'ọtụtụ isi mmalite: nzukọ, Fri Feb 13, 2009 2:50pm EST
* reuters.com, US kwa izu ethanol margins na-arị elu ruo n'elu break even, Fri Feb 13, 2009 4:01pm EST
* wired.com, Otu Molecule nwere ike ịgwọ ịṅụbiga mmanụ ókè anyị, 09.24.07

## Ịgụ ihe ọzọ