Extraction And Functional Modification Of Populus Seed Cellulose

In this paper,populus seed fibers is used as raw materials,and was treated with alkali solution（NaOH solution）,NaClO₂ solution and glacial acetic acid to extract the cellulose within it,then the content of populus seed cellulose is measured,the different time and different alkali concentration of alkali activated treatment process to populus seed cellulose is tested.AOPC has been successfully prepared by a simple two-step method.Then potassium dichromate solution is used as the waste water,the effects of absorption capacity for Cr⁶⁺such as adsorption time,pH and concentration of metal ions were analyzed.and adsorption isotherm,kinetics in the adsorption process were evaluated in batch experiments.At last,alkalization populus seed cellulose is used as raw materials,PC-g-PMMA is synthesized with Ce⁴⁺as the initiation agent,methymethacrylate as the monomer.The effects of the graft copolymerization conditions,namely temperature,reaction time and dosages of initiation agent and MMA were investigated.Structure of the graft copolymer is characterized by means of FTIR,XRD,TGA/DTA and SEM etc.In this paper,the main research results obtained are as follows:（1）When concentration of NaOH solution is 1.25 mol/L,glacial acetic acid concentration is 31 mL/L,the concentration of sodium chlorite is 9.5 g/L,alkali treatment temperature is 60 ^oC,time for alkali treatment is 90 min,bleaching treatment temperature was75 ^oC,time for bleaching treatment is 90 min,the content of populus seed cellulose is about74.2%.（2）Absorption of Cr⁶⁺by AOPC reach the balance in about 30 min,adsorption capacity with potassium dichromate solution increases with the increase of the initial concentration of potassium dichromate solution,the adsorption capacity was 70.6 mg/g for Cr⁶⁺when concentration of potassium dichromate solution was 1 g/L,and pH was 2,the absorption data of Cr⁶⁺ion by AOPC was fitted well to Langmuir isotherm,and the adsorption rate could be well fitted by pseudo-second-order rate model.（3）The best reaction conditions for oil absorption by PC-g-PMMA:reaction time is 2 h,temperature is 40 ^oC,the dosages of initiation agent is 4.5 mmol/L,the dosages of MMA is 0.8 mol/L.In this condition the grafting ratio of the modified cellulose materials is 104%,the oil absorbency ratio is 14.8g/g.Compared with the oil absorbency of unmodified populus seed cellulose（10.7 g/g）,oil absorption capacity of the modified populus seed cellulose increased by 38%.