Study On Preparation Of Biodiesel And Cationic Sizing Agent From Tall Oil

As a byproduct of coniferous wood recovered in the Kraft pulping, Tall oil is a mixture of several chemical components of great economic value, mainly fatty acids, resin acids and sterols. For its large volume of output worldwide, Tall oil is relatively cheap and it is a chemical raw material of high cost performance, with a promising application prospective. With the rapid development of paper industry in China and the wide application of Kraft pulping, the output is increasing as times goes by. But, little importance is attached to Tall oil resource domestic, and thorough research on its application is lacking. Except for those fractionated to produce fatty acids and resin acids, most of them are exported as low-end raw material, which is a waste of the resource.To have its high additional economic value applied comprehensively, Tall oil is modified and processed to produce environment- friendly biodiesel, of which the quality is tested and the components are analyzed. The residue from processing was strengthened,emulsified and cationizated to get cationic sizing agent suitable for neutral / alkaline sizing ,which is then applied and characterized , and its inner function mechanism is analyzed.The conclusions are as followed:(1) Biodiesel is obtained from crude tall oil (CTO) with acid-catalyzed. Sulfuric acid is the best catalyst, with a biodiesel yield of 46.5%; the optimal conditions are obtained by L9 (34) orthogonal and single factor analysis with 3.0% catalyst, 120min, 65℃, 75 % methanol; the properties of biodiesel from CTO fail to meet standards, but it can be used as the 0 # diesel oil;(2) Fractioned from CTO, Tall oil fatty acid (TOFA) is used as raw material to prepare biodiesel with catalysis of solid acid catalyst and assistance of ultrasonic irradiate. NKC-9-type strong acid cation-exchange resin is the best solid acid catalyst for the esterification of TOFA. The assistance of ultrasonic irradiation can improve the conversion of TOFA and reduce the reaction time; the single process factor are analyzed, the result indicates that a maximum TOFA conversion rate of 90% is obtained under the optimal conditions of 65℃, 1 h, 10:1 molar ratio of methanol to TOFA, 6% of dehydrating agent concentration and 40% of catalyst concentration ; according to the product quality testing and gas chromatography analysis, the product quality meet standards, composition of product mainly are methyl oleate and methyl linoleate, those indicate the product can be used as a high-quality biodiesel; the kinetic model parameters are calculated by MATLAB software, The kinetic model can add the missing link in ultrasonic assisted esterification reactions and the obtained values of the rate constants suitably explained the effect of the various operating parameters.(3) The tall oil sizing agent prepared from TORA is the high boiling point material after separating the TOFA from CTO. Emulsifier is the complex system of polymeric and low-molecular surfactants. The Cobb value and tensile index separately are 10.00g / m2 and 12.261N.m / g under the conditions of the 5:3 of complex ratio, sizing environment pH 5, 2% of sizing agent amount base on the dry pulp;(4) A series of cationic sizing agent(NCC-CTS, PVA-CTS and CMC-CTS) are prepared from tall oil sizing agent with synergist( NCC, PVA, CMC) and cationic reagent( PAC) , which can achieve the paper sizing in the neutral condition. CMC-CTS is the best cationic sizing agent, Cobb value of 12.67 g/m2. Zeta potential analysis showed that tall oil sizing agent can be transformed to cationic sizing agent use of cationic reagent; the particle size and chemical functional group are analyzed ,using laser particle size analyzer and FTIR and the results showed that the cationic transformation process to lead to the increases of particle size and chemical bonding occurs between the sizing agent particles,synergis(tPVA&CMC) and cationic reagen(tPAC),NCC just stabilize the emulsion; the analysis of surface contact angle of handsheet showed that the paper sizing with cationic sizing agent can reduces the surface free energy of paper , which explains the sizing mechanism.