Partially Substituting MgO for NaOH as the Alkali Source in the Second-Stage Impregnation of Triploid Poplar P-RC APMP

Hou, Qingxi; Yuan, Wei; Zhang, S. Y.; Zhao, Jinmin; Yang, Bing‐Ping; Zhang, H. J.

doi:10.1021/ie901639p

Cited by 13 publications

(14 citation statements)

References 2 publications

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“…Although the yield of lignin free CNF was higher than that of LCCNF, the yield of poplar bleached kraft pulp was much lower than that of P-RC APMP. For example, based on the typical pulping processes, the yield of P-RC APMP was approximately 88% (based on initial poplar), 47 while the yield of bleached kraft pulp was about 56% (based on initial poplar). 48 On the basis of the same amount of initial poplar chips, the generated LCCNF was about 23% higher than that of CNF.…”

Section: Acs Sustainable Chemistry and Engineeringmentioning

confidence: 99%

Preparation and Characterization of Lignin-Containing Cellulose Nanofibril from Poplar High-Yield Pulp via TEMPO-Mediated Oxidation and Homogenization

Wen

Yuan

Liu

et al. 2019

ACS Sustainable Chem. Eng.

105

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In this study, a poplar high-yield pulp [preconditioning refiner alkaline peroxide mechanical pulp (P-RC APMP)] was used to produce lignin-containing cellulose nanofibril (LCCNF) dispersions through a sequential process of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation followed by high pressure homogenization. To produce LCCNF with different lignin contents, sodium hypochlorite loadings of 4−12 mmol/g fiber during TEMPO-mediated oxidation step were explored. The effect of lignin content on morphology, thermal stability, crystallinity, and rheological properties of the produced LCCNFs was investigated. The results showed that the TEMPO-mediated oxidation of cellulose was largely limited to the fiber surface. The residual lignin on the surface of LCCNF was presented as small particles. The increase of lignin content increased the thermal stability and decreased the viscosity of the LCCNF. Moreover, at higher lignin content, greater flocculation and aggregation of fibrils took place, which resulted in lower gel-like characteristics of the resultant LCCNF. The results of water contact angle determination also demonstrated that the increase of lignin content significantly increased the hydrophobicity of the LCCNF.

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Section: Acs Sustainable Chemistry and Engineeringmentioning

confidence: 99%

Preparation and Characterization of Lignin-Containing Cellulose Nanofibril from Poplar High-Yield Pulp via TEMPO-Mediated Oxidation and Homogenization

Wen

Yuan

Liu

et al. 2019

ACS Sustainable Chem. Eng.

105

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“…It was reported (He et al, 2003; Li et al, 2005) that by applying the P M process, in which peroxide stabilisers, such as diethylenetriaminepentaacetic acid (DTPA), were added to pulp suspension prior to the addition of hydrogen peroxide and alkali source, the magnesium hydroxide based bleaching process can produce bleached mechanical pulps with similar brightness to sodium hydroxide based process. The advantages of the magnesium hydroxide‐based peroxide bleaching process, such as lower pulp yield loss, less environmental impact, are also supported by others (Hou et al, 2010; Hu and Zhang, 2009; Zeinaly et al, 2009). In addition to the open literature, there are a number of patents on using magnesium oxide or magnesium hydroxide as the alkali source for bleaching of mechanical pulps (Vincent and Alexander, 1998; Wajer et al, 2006).…”

Section: Introductionmentioning

confidence: 66%

Decreasing the peroxide decomposition in the magnesia slurry

Wekesa

2011

Can J Chem Eng

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The peroxide bleaching process for mechanical pulps using weak alkali sources such as magnesium hydroxide (Mg(OH) 2 ), received much attention recently. The magnesia slurry (containing 61.2% Mg(OH) 2 ) can be used for this purpose. In this paper, we studied the manganese-induced peroxide decomposition in commercial magnesium hydroxide slurry (magnesia). The results showed that peroxide decomposition occurs under the conditions of magnesia based bleaching process. This is due to impurities, particularly manganese in the magnesia slurry. Similar to the conventional sodium hydroxide based process, sodium silicate can effectively decrease the manganese-induced peroxide decomposition. However, the amount of silicate required is significantly less. It was found that diethylenetriaminepentaacetic acid (DTPA) or its sodium salt, can also be an effective stabiliser in the system. The chemistry of the manganese-induced peroxide decomposition was discussed.Le processus de blanchiment au peroxyde pour les pâtes mécaniques en utilisant des sources faibles telles que l'hyroxyde de magnésium (Mg(OH)2) a fait récemment l'objet d'une certaine attention. La boue de magnésie hydratée (contenant 61,2 % de Mg(OH)2) peutêtre utiliséeà cette fin. Dans cet article, nousétudions la décomposition au peroxyde induite par manganèse de boues commerciales de magnésie hydratée. Les résultats ont montré que la décomposition au peroxyde se produit dans les conditions du processus de blanchiment basé sur la magnésie. Cela est dû aux impuretés, et particulièrement au manganèse présent dans la boue de magnésie. De façon similaire au processus conventionnel basé sur l'hydroxide de sodium, le silicate de sodium peut efficacement réduire la décomposition au peroxyde induite par le manganèse. Cependant, la quantité de silicate requise est significativement inférieure. On a aussi conclu que le DTPAétait un stabilisateur efficace dans le système. La chimie de la décomposition au peroxyde induite par manganèse aétéétudiée.

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“…Recently the alkaline peroxide mechanical pulping (APMP) or the Pre-conditioning Refiner Chemcial (P-RC) APMP, has become popular, particularly in China. The charge demand of the resulting pulp would be similar to that of peroxide bleached mechanical pulps (Hou et al 2010).…”

Section: Peroxide Bleaching Of Mechanical Pulpmentioning

confidence: 97%

Dissolved and Colloidal Substances (Dcs) and the Charge Demand of Papermaking Process Waters and Suspensions: A Review

et al. 2012

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Dissolved and colloidal substances (DCS) in the process waters of paper machine systems can interfere with the retention of fine particles, retard the drainage of water from the wet web, and generally hurt the intended functions of various polyelectrolytes that are added to the process. This review considers publications that have attempted to characterize the nature and effects of different DCS fractions, in addition to some of the ways that paper technologists have attempted to overcome related problems. The consequences of DCS in a paper machine system can be traced to their ability to form complexes with various polyelectrolytes. Such tendencies can be understood based on a relatively strong complexing ability of multivalent materials, depending on the macromolecular size and charge density. Continuing research is needed to more fully understand the different contributions to cationic demand in various paper machine systems and to find more efficient means of dealing with DCS.

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Partially Substituting MgO for NaOH as the Alkali Source in the Second-Stage Impregnation of Triploid Poplar P-RC APMP

Cited by 13 publications

References 2 publications

Preparation and Characterization of Lignin-Containing Cellulose Nanofibril from Poplar High-Yield Pulp via TEMPO-Mediated Oxidation and Homogenization

Preparation and Characterization of Lignin-Containing Cellulose Nanofibril from Poplar High-Yield Pulp via TEMPO-Mediated Oxidation and Homogenization

Decreasing the peroxide decomposition in the magnesia slurry

Dissolved and Colloidal Substances (Dcs) and the Charge Demand of Papermaking Process Waters and Suspensions: A Review

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