Acacia crassicarpa: Midgley, S. & Thomson, L.

2018 ◽  
Author(s):  
Keyword(s):  
Acacia Crassicarpa

scholarly journals Aplikasi Lakase pada Proses Refining Pulp

2019 ◽  
Vol 9 (02) ◽  
pp. 65
Author(s):  
Hendro Risdianto ◽  
Sonny Kurnia Wirawan ◽  
Susi Sugesty
Keyword(s):  
Reaction Rate ◽  
Refining Process ◽  
Enzyme Treatment ◽  
Paper Strength ◽  
Tensile Index ◽  
Tear Index ◽  
Acacia Crassicarpa

Refining merupakan proses untuk memodifikasi serat dengan tujuan meningkatkan ikatan serat dan mengembangkan kekuatan kertas. Penelitian yang telah dilakukan meliputi penentuan kondisi refining dengan PFI Mill dan penentuan kondisi perlakuan awal lakase yang selanjutnya akan diterapkan pada proses biorefining. Jumlah putaran 2500 dari PFI mill merupakan jumlah yang optimum untuk menghasilkan kekuatan pulp Acacia crassicarpa. Sedangkan hasil penelitian kondisi optimum lakase menunjukkan bahwa lakase memiliki laju reaksi yang paling tinggi (0,0018 mM/s) pada suhu 50°C. Pada proses refining, freeness awal pulp adalah sekitar 550 mL CSF, dan ketika dikenakan perlakuan lakase turun menjadi 515 (LMS1) dan 520 (LMS2). Refining pulp tanpa perlakuan enzim menghasilkan indeks tarik, retak dan sobek berturut-turut adalah 6,4.10-2 kNm/g, 5,18 kPa.m2/g, dan 5,96 mN.m2/g. Indeks sobek tidak mengalami perubahan signifikan pada semua perlakuan. Perlakuan LMS1 meningkatkan indeks tarik menjadi 6,83 kNm/g dan indeks sobek menjadi 7,53 mN.m2/g. Indeks tarik dan sobek pada LMS2 menurun dibandingkan LMS1, namun masih lebih tinggi dibandingkan tanpa perlakuan. Dengan demikian perlakuan lakase pada proses refining dapat meningkatkan indeks tarik dan indeks sobek lembaran.Laccase Application in Pulp Refining Process AbstractRefining is a process to modify fibers with the aim of increasing fiber bonds and developing paper strength. The research that has been done includes determining the refining conditions with PFI Mill and determining the conditions of pretreatment of laccase which will then be applied to the biorefining process. The PFI mill revolutions of 2500 is the optimum to produce the strength of the Acacia crassicarpa pulp. Whereas the results of the study showed that optimum laccase conditions showed that laccase had the highest reaction rate (0.0018 mM/s) at 50oC. In the refining process, the initial freeness of the pulp is around 550 mL CSF, and when subjected to laccase treatment it drops to 515 (LMS1) and 520 (LMS2). Refining the pulp without enzyme treatment produced tensile, bursting and tearing indexes of 6.4.10-2 kNm/g, 5.18 kPa.m2/g, and 5.96 mN.m2/g, respectively. The tear index did not change significantly in all treatments. The LMS1 treatment increased the tensile index to 6.83 kNm/g and the tear index to 7.53 mN.m2/g. The tensile and tear index in LMS2 decreased compared to LMS1, but it was still higher than without treatment. Thus, laccase treatment in the refining process can increase the tensile index and tear indexof the sheet.  

Acacia crassicarpa (northern wattle).

2021 ◽  
Author(s):  
Nick Pasieczni ◽  
Duncan McDonald
Keyword(s):  
Imperata Cylindrica ◽  
Low Fertility ◽  
Soil Types ◽  
Weed Species ◽  
Root Nodulation ◽  
Seasonally Dry ◽  
Dry Tropics ◽  
Acacia Crassicarpa ◽  
Round Timber ◽  
Pulp Production

Abstract A. crassicarpa is one of the fastest-growing acacias for planting on degraded sites in the seasonally-dry tropics. It tolerates a range of soil types, particularly those of low fertility. It is a nitrogen-fixing tree that produces abundant natural root nodulation. It is fire resistant and competes favourably against weed species such as Imperata cylindrica. It has the potential to produce a dense hardwood that can be used in industrial pulp production, as sawn or round timber for construction or as fuelwood.

Acacia crassicarpa A. Cunn. ex Benth. (Fabaceae) as a Host Plant of Five Species in the Genera Altica Geoffroy, Aulacophora Dejean, and Aulonogria Borchmann (Coleoptera: Chrysomelidae, Tenebrionidae) in Sumatra, Indonesia

2020 ◽  
Vol 74 (4) ◽  
Author(s):  
Wagner De Souza Tavares ◽  
Donny Christal Ginting Suka ◽  
Dedi Hardi ◽  
Rikky Adriya ◽  
Nike Grace Hanjelina br sinulingga ◽  
...  
Keyword(s):  
Host Plant ◽  
Acacia Crassicarpa

scholarly journals Diversité Et Structure Floristiques Sous Des Peuplements d’Acacias Australiens En Zone Forestière De La Côte d’Ivoire

2016 ◽  
Vol 12 (35) ◽  
pp. 229
Author(s):  
Kouadio Kouassi Richard ◽  
Bakayoko Adama ◽  
N’guessan Kanga Anatole ◽  
Konan Djezou
Keyword(s):  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Acacia Mangium ◽  
Research Station ◽  
Cote D’Ivoire ◽  
Acacia Species ◽  
Côte D'ivoire ◽  
African Flora ◽  
Acacia Crassicarpa ◽  
The Impact

Since thirty years, four Australian Acacias species are introduced and studied in Anguédédou Research station. The station research is located in evergreen forest in the south of Côte d'Ivoire. The objective of the introduction of these species, is to rehabilitate degraded grounds and fallow after growing. The study aims at appreciating the impact of Acacia species on floristic diversity and the regeneration of forest species. For collecting data, we use quadrat method (35 x 50 m and 6 x 6 m).This method permitted the inventory of 212 species on 1.05 ha. Among these species, 1.89 % are Ivorian endemic species and 11.32 % are endemic of West African flora. The flora under the different species of Acacia are relatively diversified and dense. The majority of plant inventoried under Acacia species have small diameters. The highest specific richness average per plots (36 m2) were noted in the 11 years old parcels of Acacia mangium (26.20±2.34) and 27 years old parcels of Acacia auriculaeformis (25.40±2.34) and Acacia crassicarpa (30.60±2.34). The mean values of diameters (dbh ≥ 2.5 cm) fluctuate from 2.94±0.56 cm for the 8 years old stands of Acacia mangium to 8.09±0.56 cm for the 27 years old settlements of Acacia crassicarpa. The results show that leguminous trees can be used for recolonization of the deforested areas in order to rebuild quickly their plant biodiversity.

scholarly journals PENGGUNAAN XILANASE PADA PEMUTIHAN DISSOLVING PULP Acacia crassicarpa

2015 ◽  
Vol 5 (02) ◽  
Author(s):  
Susi Sugesty ◽  
Teddy Kardiansyah ◽  
Wieke Pratiwi
Keyword(s):  
Chlorine Dioxide ◽  
Dissolving Pulp ◽  
Raw Material ◽  
National Standard ◽  
Cellulose Content ◽  
Pulp Bleaching ◽  
Elemental Chlorine ◽  
Free Process ◽  
Acacia Crassicarpa ◽  
Prehydrolysis Kraft

The use of xylanase in pulp bleaching process is intended to reduce chemicals consumption in pulp industry that still using chlorine compounds (chlorine dioxide), so the bleaching stage needs to be modified without reducing the quality of dissolving pulp. Dissolving pulp was produced from six-year-old Acacia crassicarpa as raw material by the Prehydrolysis-Kraft process, then the pulp was bleached with the ECF (elemental chlorine free) process using xylanase (X) and oxygen (O) as comparison at the early stage of bleaching. The sequences of process include X/ODEDED (xylanase or oxygen; chlorine dioxide; extraction-1; chlorine dioxide-1; extraction-2; chlorine dioxide -2). Results showed that the dissolving pulp with active alkali of 22%, sulphidity of 30%, the temperature of 165oC, and the ratio of 1:4 is the optimal condition. Cellulose content, viscosity and brightness were above 94%, 6.2 cP and 88% ISO, respectively.The dissolving pulp produced with the application of xylanase has better quality than the oxygen one, and meets the requirement according to Indonesia National Standard (SNI 0938:2010, pulp rayon).Keywords: Acacia crassicarpa, xylanase, Prehydrolysis-Kraft, dissolving pulp, rayon pulpABSTRAKPenggunaan xilanase pada proses pemutihan pulp dimaksudkan untuk mengurangi konsumsi bahan kimia yang digunakan selama ini di industri pulp, yang masih menggunakan senyawa klorin (klorin dioksida), untuk itu perlu dilakukan modifikasi pada tahap pemutihannya tanpa mengurangi kualitas dissolving pulp yang dihasilkan. Pembuatan dissolving pulp dilakukan menggunakan bahan baku kayu Acacia crassicarpa berumur 6 tahun dengan proses Prahidrolisa–Kraft, selanjutnya pulp diputihkan dengan proses ECF (Elemental Chlorine Free) menggunakan xilanase (X) dan oksigen (O) sebagai pembanding pada awal pemutihan dengan 6 tahapan proses, yaitu X/ODEDED (xilanase atau oksigen; klorin dioksida; ekstraksi-1; klorin dioksida-1; ekstraksi-2; klorin dioksida-2) dengan perlakuan oksigen sebagai pembanding. Hasil pembuatan dissolving pulp dengan alkali aktif 22%, sulfiditas 30%, suhu 165oC, rasio 1:4 adalah kondisi yang optimal. Kandungan selulosa, viskositas dan derajat cerah yang diperoleh masing-masing yaitu di atas 94%, 6,2 cP dan 88% ISO. Kualitas dissolving pulp hasil pemutihan dengan penambahan xilanase lebih tinggi daripada menggunakan oksigen dan memenuhi persyaratan spesifikasi SNI 0938:2010, pulp rayon. Kata kunci : Acacia crassicarpa, xilanase, Prahidrolisa-Kraft, dissolving pulp, pulp rayon

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