Black liquor, kraft

The feasibility of electrochemically recovering pure sodium hydroxide and lignin from kraft black liquor has been explored in several studies. Electrodialy-... 

Burning of cables and electromotors Drum and barrel reclamation Forest fires Kraft black liquor boilers Cigarette smoking Charcol briquette combustion Various high-temp. 

Analysis of small ions has been published for many applications other than pharmaceutical applications, and has a growing impact in industrial, environmental, biomedical, clinical, and forensic laboratories. Sample matrices range from simple tap water to Kraft black liquor, including river and seawater, beer and wine, environmental water, and nuclear plant water, but also body fluids such as serum, urine, plasma, cerebrospinal fluid, and many others. Those topics alone would require a separate book. 

Table 4 Components of Kraft Black Liquor and Characteristics of Kraft Evaporator Condensate...

Figure 11. Fractionation of low molar mass lignin components in kraft black liquor. Column Sephadex G-25. Eluent 0.5M NaOH.

Figure 10. Fractionation of spruce spent sulfite liquor and pine kraft black liquor.

Hagglund and Enkvist (6) developed a laboratory scale method for manufacturing methyl sulfide from kraft black liquor by pressure heating after addition of sodium sulfide. This process was later taken over by Crown-Zellerbach in the United States and developed in pilot plant and full scale. However, the yield is only about 7% of the initial lignin utilized in the process. 

Kraft Lignin. A softwood kraft lignin (KL) was isolated from a partly evaporated, industrial kraft black liquor by precipitation through the addition of dilute sulfuric acid as described elsewhere (7). The lignin was thereafter fractionated by successive extraction with organic solvents (7). The KL fraction used in the present investigation was the second of five fractions obtained (propanol soluble - methylene chloride insoluble). 

Starting Material. A drum of concentrated, mixed, southern pine kraft black liquor was kindly supplied by the Canton, N. C. mill of the Champion Paper and Fibre Co. Analytical data for the liquor indicated 49.7% total solids and a methoxyl content of the oven-dried solids of 5.54%. The pH of the liquor as received was 12.3. (All melting points are uncorrected. Infrared absorption spectra were determined by Mr. Lowell Sell of The Institute of Paper Chemistry Analytical Group.)... 

In addition, the discovery of phthalic acid as a major oxidation product is theoretically important with respect to the linkages in alkali lignin obtained from kraft black liquor and, therefore, to the mechanism of the kraft cook. 

In addition to in situ soil applications, Fenton reagent has also been studied for treatment of industrial waste streams. For example, the treatment of residual Kraft black liquor from the pulp-and-paper industry has been shown to be effective [42]. Near-complete degradation of lignin (95-100%) and decolorization were achieved under optimized conditions. Basic oxygen furnace slag was evaluated as a source of iron for degradation of 2-chloro-phenol in industrial wastewater [43], and favorable results were achieved. 

Araujo E, Rodriguez-Malaver AJ, Gonzalez AM, Rojas OJ, Penaloza N, Bullon J, Lara MA, Dmitrieva N. Fenton s reagent-mediated degradation of residual kraft black liquor. Appl Biochem Biotechnol 2002 97 91-103. 

Numerous attempts have been made to produce other low molecular weight products from lignin by subjecting concentrated kraft black liquors directly to various treatments, including hydrogenation, oxidation, or only heating in the presence of excess alkali. 

AI6n, R., Patja, P., and Sjostrom, E. (1979). Carbon dioxide precipitation of lignin from pine kraft black liquor. Tappi 62(11), 108-110. 

Kontturi AK, Sundholm G (1986) The extraction and fractionation of lignosulfonates with long chain aliphatic amines Acta Chem Scand 40 121-125 Wada S, Iwamida T, Iijima R, Yabe K (1962) Fractional precipitation of kraft black liquor from spruce wood Chem High Polymers (Kabunshi Kagaku) 19 699-705... 

Niemela K (1988) GLC MS studies on pine kraft black liquors Part I Identification of monomeric compounds Holzforschung 42 169-173... 

Hill M, Fricke A (1984) Ultrafiltration studies on a kraft black liquor. Tappi J 67(6) 100-103 Klinkowski PR (1978) An emerging unit operation. Chem Eng 8 165-173 Lin SY, Detroit WJ 1981 Heterogeneity of technical lignins - its significance in lignin utilization. Proc 1981 Int Symp Wood Pulp Chem. Ekman-Days 1981 (Stockholm). SPCI Rep 38,4 44-52... 

Wilson KP, Laver ML, Frederick WJ (1986) Ultrafiltration of kraft black liquor membrane performance and liquor characteristics. Proc AIChE Summer Natl Meet (Boston) Aug 24-27, 1986, Preprint 67c 26p... 

The steam pyrolysis of kraft black liquor to yield specific phenolic compounds by thermal decomposition. 

Cortinas et al. [89] eliminated colloidal suspended material (pitch) from kraft black liquors and partly recycled the liquor to the digester to reduce the consumption of chemicals. The colloidal pitch is formed by wood extractives. In particular, compounds such as waxes, sterols, and sterol esters that do not form soluble salts or dissolve during cooking form colloidal particles. The concentrated liquors (14%-15% solids) were filtered at high temperature using a 0.2 xm alumina membrane (USF Shumacher, Crailsheim, Germany). The pitch was almost completely retained (>99.9%), but the flux was sensitive to the black liquor composition and sometimes decreased to less than 100 L/(m h). 

Luque S, Rodriguez M, Alvarez JR, and Coca J. Kraft black liquor fractionation by ultrafiltration. 1994 Pulping Conference, San Diego, CA, November 6-10, 1994. 

De S and Bhattacharya PK. Recovery of water and inorganic chemicals from kraft black liquor using membrane separation processes. TappiJ. 1996 79(1) 103-111. 

Wallberg O, Jonsson A-S, and Wimmerstedt R. Fractionation and concentration of kraft black liquor lignin with ultrafiltration. Desalination 2003 154 187-199. 

Satyanarayana SV, Bhattacharya PK, and De S. Flux decline during ultrafiltration of kraft black liquor using different flow modules A comparative study. Sep. Pur. Techn. 2000 20 155-167. 

Bhattacharjee S, Siddhartha D, and Bhattachaijee C. Performance study during ultrafiltration of kraft black liquor using rotating disk membrane module. J. Cleaner Production 2006 14(5) 497-504. 

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