Cellulose yog ib qho derivative ntawm ob yam ntuj tsim: ntoo thiab paj rwb. Hauv cov nroj tsuag, nws ua haujlwm tseem ceeb, muab lawv yooj yim thiab lub zog.
Cov khoom nyob qhov twg?
Cellulose yog ib yam khoom ntuj. Cov nroj tsuag muaj peev xwm tsim tau ntawm lawv tus kheej. Muaj: hydrogen, oxygen, carbon.
Nroj tsuag tsim cov suab thaj hauv qab lub hnub ci, nws ua tiav los ntawm cov hlwb thiab ua rau cov fibers tiv taus cov khoom hnyav los ntawm cua. Cellulose yog ib yam khoom uas koom nrog hauv cov txheej txheem ntawm photosynthesis. Yog tias cov dej qab zib tau nchuav rau ntawm tsob ntoo tshiab, cov kua yuav nqus sai sai.
Pulp ntau lawm pib. Qhov no ntuj txoj kev tau txais nws yog coj los ua lub hauv paus rau zus tau tej cov paj rwb ntaub ntawm ib tug muaj scale. Muaj ntau txoj hauv kev los ntawm cov khoom siv ntawm ntau yam zoo.
YProduction Method 1
Tau txais cellulose tshwm sim ib txwm - los ntawm cov noob paj rwb. Cov plaub hau yog sau los ntawm automated mechanisms, tab sis lub sij hawm ntev loj hlob yuav tsum tau rau cov nroj tsuag. Cov ntaub uas tsim nyob rau hauv txoj kev no suav hais tias yog purest.
Pulp tuaj yeem tau sai dua los ntawm cov ntoo fibers. Txawm li cas los xij, qhov zoo yog qhov phem dua nrog txoj kev no. Cov khoom siv no tsuas yog siv rau kev tsim cov yas uas tsis yog fiber ntau, cellophane. Tsis tas li, cov khoom siv fiber ntau tuaj yeem tsim los ntawm cov khoom siv zoo li no.
Natural txais
Kev tsim cov cellulose los ntawm paj rwb noob pib nrog kev sib cais ntawm cov fibers ntev. Cov khoom no yog siv los ua paj rwb ntaub. Qhov me me, tsawg dua 1.5 cm, yog hu ua paj rwb fluff.
Lawv haum rau kev tsim cov pulp. Cov khoom sib dhos yog raug rau cov cua kub siab. Lub sijhawm ntawm cov txheej txheem tuaj yeem ncav cuag 6 teev. Ua ntej pib ua kom sov cov khoom, sodium hydroxide ntxiv rau nws.
Cov khoom tshwm sim yuav tsum tau ntxuav. Rau qhov no, chlorine yog siv, uas kuj bleaches. Cov muaj pes tsawg leeg ntawm cellulose nrog rau txoj kev no yog purest (99%).
Kev tsim khoom 2 ntawm ntoo
Kom tau txais 80-97% ntawm cov ntaub so ntswg, cov khoom siv ntoo thiab cov tshuaj siv tshuaj. Tag nrho cov loj yog tov thiab raug rau kev kho kub. Raws li kev ua noj, cov khoom xav tau raug tso tawm.
Sib xyaw calcium bisulfite, sulfur dioxide thiab ntoo pulp. Cellulose nyob rau hauv lub resulting sib tov yog tsis ntau tshaj 50%. Raws li qhov tshwm sim ntawm cov tshuaj tiv thaiv, hydrocarbons thiab lignins yaj hauv cov kua. Cov khoom siv tau raug ntxuav.
Tau ib pawg zoo li daim ntawv tsis zoo. Cov khoom siv no yog lub hauv paus rau kev tsim cov tshuaj:
- Ethers.
- Cellophane.
- Viscose fiber ntau.
Yuav ua li cas los ntawm cov khoom muaj nqis?
Cov qauv ntawm cellulose yog fibrous, uas ua rau nws muaj peev xwm ua khaub ncaws los ntawm nws. Cov khoom siv paj rwb yog 99.8% natural khoom tau los ntawm cov txheej txheem ntuj saum toj no. Nws kuj tseem siv tau los ua cov khoom tawg vim muaj tshuaj lom neeg. Cellulose ua haujlwm thaum cov kua qaub rau nws.
Cov khoom ntawm cellulose muaj feem xyuam rau kev tsim cov ntaub. Yog li, cov khoom siv fiber ntau yog tsim los ntawm nws, zoo li cov ntaub ntuj tsim thiab kov:
- viscose thiab acetate fibers;
- faux fur;
- tooj liab ammonia silk.
Mainly ua los ntawm ntoo pulp:
- varnishes;
- thaij duab;
- khoom siv;
- plastics;
- daim txhuam cev;
- smokeless hmoov.
Raws li cov tshuaj tiv thaiv los ntawm cellulose tau:
- trinitrocellulose;
- dinitrofiber;
- glucose;
- roj ua kua.
Hauv zaub mov, cellulose kuj siv tau. Qee cov nroj tsuag (celery, lettuce, bran) muaj nws cov fibers. Nws kuj yog ib qho khoom siv rau kev tsim cov hmoov txhuv nplej siab. Peb twb tau kawm yuav ua li cas kom nyias threads los ntawm nws - lub web tsim muaj zog heev thiab tsis stretch.
Cov tshuaj formula ntawm cellulose yog C6H10O5. Nws yog polysaccharide. Nws yog tsim los ntawm:
- kho mob paj rwb;
- bandages;
- tampons;
- daim ntawv, chipboard;
- khoom noj khoom haus ntxiv E460.
Pulp tuaj yeem tiv taus qhov kub siab txog 200 degrees. Cov molecules tsis tawg, uas ua rau nws muaj peev xwm ua reusable yas tais los ntawm nws. Nyob rau tib lub sijhawm, qhov tseem ceeb zoo yog khaws cia - elasticity.
Cellulose tiv taus cov kua qaub ntev. Insoluble kiag li nyob rau hauv dej. Tsis zom los ntawm tib neeg lub cev, siv los ua sorbent.
Microcrystalline cellulose yog siv rau hauv lwm cov tshuaj raws li lub plab zom mov. Cov hmoov hmoov ua raws li cov khoom noj ntxiv kom txo cov calorie ntsiab lus ntawm cov tais diav. Qhov no pab tshem tawm cov co toxins, txo cov ntshav qab zib thiab cov cholesterol.
Kev tsim khoom 3 - Industrial
Ntawm qhov chaw tsim khoom, pulp yog npaj los ntawm kev ua noj hauv ntau qhov chaw. Cov khoom siv yog nyob ntawm hom reagent - hom ntoo:
- Resinous pob zeb.
- Txoj ntoo txiav.
- Nplooj.
Muaj ntau hom kev ua noj ua haus:
- Acidic ib puag ncig. Txwv tsis pub, txoj kev raug xa mus rau sulfite. Raws li kev daws, ntsev ntawm sulfurous acid los yog nws cov kua sib tov yog siv. Nrog rau qhov kev xaiv ntau lawm, cellulose yog cais los ntawm hom coniferous. Fir thiab spruce tau ua tiav zoo.
- Cov txheej txheem alkaline nruab nrab lossis dej qab zib yog raws li kev siv sodium hydroxide. Cov tshuaj zoo cais cellulose los ntawm cov nroj tsuag fibers (pob kws stalks) thiab ntoo (tseem ceebhardwood).
- Kev siv ib txhij ntawm sodium hydroxide thiab sodium sulfide yog siv hauv txoj kev sulfate. Nws yog dav nkag mus rau hauv kev tsim cov cawv dawb sulfide. Cov thev naus laus zis tsis zoo rau ib puag ncig vim qhov tshwm sim ntawm cov tshuaj lom neeg thib peb.
Txoj kev kawg yog qhov feem ntau vim tias nws muaj ntau yam: pulp tuaj yeem tau los ntawm yuav luag txhua tsob ntoo. Txawm li cas los xij, purity ntawm cov khoom yog tsis siab heev tom qab ib tug boil. Impurities tshem tawm cov tshuaj tiv thaiv ntxiv:
- hemicelluloses raug tshem tawm nrog cov tshuaj alkaline;
- Lignin macromolecules thiab lawv cov khoom puas tsuaj raug tshem tawm nrog cov tshuaj chlorine tom qab kho nrog alkali.
Tus nqi noj zaub mov
Starch thiab cellulose muaj cov qauv zoo sib xws. Raws li qhov tshwm sim ntawm kev sim, nws tuaj yeem tau txais cov khoom tseem ceeb ntawm cov fibers inedible. Nws xav tau ib tug neeg tas li. Cov zaub mov koj noj yog ntau tshaj 20% starch.
Cov kws tshawb fawb tau tswj hwm kom tau txais amylose los ntawm cellulose, uas muaj txiaj ntsig zoo rau lub xeev ntawm tib neeg lub cev. Tib lub sijhawm, cov piam thaj tso tawm thaum lub sijhawm cov tshuaj tiv thaiv. Nws hloov tawm cov khoom tsis muaj pov tseg - cov khoom kawg raug xa mus rau kev tsim cov ethanol. Amylose kuj tseem siv tau los tiv thaiv kev rog.
Raws li qhov tshwm sim ntawm cov tshuaj tiv thaiv, cov cellulose tseem nyob hauv lub xeev ruaj khov, nyob rau hauv qab ntawm lub nkoj. Cov khoom seem raug tshem tawm siv cov hlau nplaum nanoparticles los yog yaj thiab tshem tawm nrog cov kua.
Tim khoom muag
Cov khoom lag luam muab cov ntawv sib txawv ntawm tus nqi tsim nyog. Peb teev cov khoom tseem ceeb:
- Sulfate dawb cellulose, ua los ntawm ob hom ntoo: coniferous thiab hardwood. Muaj cov khoom siv tsis huv siv hauv cov khoom ntim, cov ntawv tsis zoo rau cov ntaub ntawv insulating thiab lwm yam siv.
- Sulfite kuj muaj nyob rau hauv dawb, ua los ntawm cov ntoo coniferous.
- Cov khoom siv hmoov dawb haum rau kev tsim cov tshuaj kho mob.
- Qib qib cellulose yog tsim los ntawm tshuaj dawb tsis muaj tshuaj chlorine. Conifers raug coj los ua raw khoom. Cov ntoo pulp muaj kev sib xyaw ntawm spruce thiab ntoo thuv chips hauv qhov sib piv ntawm 20/80%. Lub purity ntawm cov khoom tshwm sim yog qhov siab tshaj plaws. Nws yog tsim los ua cov ntaub ntawv tsis muaj menyuam siv hauv tshuaj.
Cov txheej txheem yog siv los xaiv cov ntaub ntawv tsim nyog: cov khoom siv purity, tensile lub zog, fiber ntau ntev, tsim kua muag index. Cov tshuaj lom neeg lub xeev los yog aggressiveness ntawm cov aqueous extract nruab nrab thiab cov av noo kuj qhia quantitatively. Rau cov khoom siv bleached, lwm yam tsis siv: ntim tshwj xeeb, ci ntsa iab, dawb, tensile zog, purity.
Qhov taw qhia tseem ceeb rau qhov loj ntawm cellulose yog lub kua muag tiv thaiv qhov ntsuas. Lub hom phiaj ntawm cov khoom tsim nyob ntawm nws. Hom ntoo siv los ua cov khoom siv raw thiab cov av noo yog muab rau hauv tus account. Tseem ceeb heevresin thiab rog theem. Hmoov uniformity yog ib qho tseem ceeb rau tej yam kev siv cov txheej txheem. Rau cov laj thawj zoo sib xws, qhov toughness thiab bursting zog ntawm cov khoom nyob rau hauv daim ntawv ntawm cov nplooj ntawv raug soj ntsuam.
