Q&A
Did you. miss any of the questions that was posted in Q&A during the conference? Here you find the Q&A report. For the questions that was answered live is only the question is included.
September 23
Q: This is a boring question but how much would the cost increase by scavenger addition
Ola Wallberg
A: live answered
Q: We have different colors on the milk packages in the south __
Ola Wallberg
A: live answered
Q: Have you considered SO2
Ola Wallberg
A: Yes, it has been discussed, intitially we considered a sulfur free process and it was dismissed, moving along with the second study we went for H2SO4 because SO2 is much more demanding in continuous pilot scale and would require rebuilds. In addition there is a some restistance towards using SO2 within parts of the industry
Q: Is glucose your ultimate product you want to get out from bark? or also other chemicals?
AnhPham
A: The first step was to evaluate the 2-naphtol addition which was done trough enzymes and glucose production. However that is not necessarily the end product. It is still open questin since we produce a densified commodity
Q: Have you tested a much lower enzyme charge? At very high charges, the enzyme itself could inhibit the enzyme reactivity.
Niklas
A: live answered
Q: Do you have any idea on how an industrial hemicellulose solution would affect the process.? Does hemicellulose purity have a influence. Relating back to last week’s treesearch dissertation by Basel Al-rudainy in Lund.
Ola Wallberg
A: I have no hypothesis regarding this, but will for sure have a closer look at that dissertation!
Q: 1. Can you put numbers to the viscosity values when you mix with hemicellulose? The increase of viscosity seems to be important as well. 2. Can you comment what you mean by dry and water resistant test? (Is dry 0% humidity as well/is water resistant a test under water?)”
Ramiro Rojas
A: live answered
Q: What about water resistance properties for using hemicellulose ad adhesive? Is it in the acceptable range?
Atanu Kumar Das
A: live answered
Q: Has Ga:Ma ratio affected bonding strength?
AnhPham
A: Carbohydrate analysis showed that all samples had almost the same Ga:Ma ratio so we didn«t analyze that in this study. It could be analyzed by using different galactomannans, with different Ga:Ma ratio
Q: Locus bean gum and Xanthan interacts very strongly, do you think that GGM and locus bean gum can interact more strongly than expected and give a better glue?
Anette Larsson
A: Yes. For now we analyzed only Locust bean gum, but it would be interesting to combine it Xanthan gum
Q: Maybe I missed in your presentation but what is the benchmark bond strength with current adhesives?
Agne Swerin
A: We are using commercial PVAc as a benchmark in our studies. According to standard for wood adhesives, bond strength should be above 8 MPa, but at this moment I can«t recall exact value. In this study, adhesives showed lower strength, but we used lower dry content than usually used in commercial adhesives.
Q: Thank you for the presentation;
Lars Wågberg
A: live answered
Q: Thank you for a nice presentation.Is it possible to confirm the covalent bond between AKD and cellulose?
Eva Malmström Jonsson
A: live answered
Q: 2 questions 1. TMP has a high concentration of lignin on the surface. How do you know that the AKD reacts with the cellulose? 2. How do you add the non-water soluble AKD?
Lars Wågberg
A: live answered
Q: Eshan, did you already confirm increased hydrophobicity of TMP-AKD fibers using one and two steps?
Agne Swerin
A: live answered
Q: What is your target composite?
Atanu Kumar Das
A: we are aiming for a composite that is at least 70 w% TMP plus a commercial polymer like PP or PE and we need to process it in an extrusder as it is a continuos process
Q: ’@Ehsan, thank you very much for the interesting presentation. Nice synthesis of the well-defined AKD also. Has the route been published yet? If yes, where?
Eva Malmström Jonsson
A: Thanks Eva, not yet, I hope we will submit my project about additives end of november and the AKD project we need more analysis and we are aiming for JAnuary-February next year
Q: Eshan, only a comment. I can give you some hints off-line on how to proceed using e.g. single fiber contact angles in a Wilhelmy set-up. Give me a call at +46768640031 or agne.swerin@kau.se
Agne Swerin
A: Hi Agne Thank you very much I will surely contact you
Q: Thanks – I was just cuiroius if GGM and Locus bean gum could give these cool interactionsis. Maybe not so likely, but if then it would be really beneficial. /Anette
Anette Larsson
A: It was not aim of this study but I do think it would be good to investigate that too in the future
Q: Hi Vishnu! Which anions are you interested in studying? Which ones are relevant for the pulp industry?
Barbara Berke
A: live answered
Q: A comment: Consider the properties of the ions such as polarizability. Calcium ions are more polarizable which means that it will adsorb to the fibers and make them slightly cationic.
Tobias Benselfelt
A: live answered
Q: Vishnu, is there same type of interaction with already present hemicelluloses that you find for CMC and are you planning to study this?
Agne Swerin
A: live answered
Q: Great! If you go to barium ions you will probably see more adsorption.
Tobias Benselfelt
A: Yes I tried that as well. It was effecient than calcium. Since from an industrial perspective that is not viable that why i didnt present it here.
Q: Regarding visibility of presentation vs presenter video: There are two thin vertical lines between the presentation and the presenter video. If you hoover over them you can drag left or right to adjust the size of the presentation vs the presenter video.
Linda Fogelström
A: Perfect! Thank you Linda.
Q: To Kristofer Robertsson: Thanks for this very interesting presentation of this advanced modelling. I wonder, what kind of plasticity model are you using, and to you account for differences in tension and compression in that plasticity model? /Gustav Lindberg
Gustav Lindberg
A: Hi Gustav, the plasticity model is not a standard one. It has no formal name, it was inspired by crystal plasticity and and was first introduced by a guy named Xia. The model consits of several subsurfaces and is therefore very flexiable, in this sence the in-plane plastic behavior between compresssion and tension can be modeled seperatly.
Q: Ah ok, I understand. I appreciate your answer. Thanks!
Gustav Lindberg
A: live answered
Q: To Yunus: If used in your example of smart filter, would the material hold together even at this high degree of swelling?
OskarWe
A: Hey oskar, I forgot t mention, the smart fileters are deposited on whatman filter papers in a matter of seconds so that’s what holds them together
Q: Very nice presentation Yunus, exemplary in describing both research and engineering goals.
Ramiro Rojas
A: Thank you very much Ramiro!
Q: Is it possible to use very low pH in papermaking process?
Atanu Kumar Das
A: Hi, a pH of 4.8 as a minimum is preferred for the pper machine currently we are at pH 3 wihtout using anything. However with the help of dewatering aids etc we are sure that the pH can be brought up to a higher level. Paper can be made at higher pH values as well but it increases the dewatering time due to swelling
Q: Yunus, I probably missed but what is the periodate addition required? How do you explain mechanistically the rapid dewatering?
Agne Swerin
A: Hi Agne! We believe it’s the hemiacetals at low pH since it prevents swelling. We have seen before from Per Larsson’s work that dialdehyde cellulose dewaters very fast. We can also achieve very fast dewatering if we increase the salt content so I think it is directly related to swelling and how it is counteracted by salts and/or hemiacetal crosslinks
Q: Maybe it is just me. Sound is not clear. It keeps breaking up.
Basel Al-Rudainy
A: live answered
Q: There has been a lot of recent breakthroughs regarding lignin molecular structure yet , generally speaking, it is used in materials applications we donÕt know much about the nature of the lignin. What do you suggest to be the minimum analysis to report in materials science articles that use lignin? We need to stop calling lignin to any brown or dark powder.
Ramiro Rojas
A: 2D NMR and PNMR
Q: Q2: does your data suggest that lower MW fractions of softwood are less reactive due to more aromaticity (steric hindrance) and less aliphatic hydroxyls?
Ramiro Rojas
A: If the aliphatic chain is you reactive side that is right. If the reactive sides are phenolic, then is the opposite
September 24
Q: Thank you for an interesting presentation, nice work. Are you thinking of alternative chemicals instead of formaldehyde as it is a hazardous chemical?
Eva Malmström Jonsson
A: Not in this step, becasue formaldehyde is a main reactant in this phase of project.
–
Q: Do you have any consideration of natural depolymerization of lignin in your composite?
Atanu Kumar Das
A: Maybe it is too soon, because reaching an acceptable mechanical properties is our first goal, we would like to acheive.
–
Q: ’@mohammaad morsali: Sorry if I missed it if you talked about it during the presentation, but can you comment on the biodegradability of your composites. Will you evaluate this feature?
Linda Fogelström
A: We believe this is a very interesting subject to be studied, and definitly we will consider it.
–
Q: What is the driving force of lignin-based coating research? Do you know how is industry interest on bio-based coating, especially lignin-based coating?
AnhPham
A: live answered
–
Q: A question for the first two speakers. Which properties would you like the lignin starting material to have? There are several industrial sources of lignin, and several more can be consieved in a more advanced biorefinery industry in the future.
Ola Wallberg
A: live answered
–
Q: Thank you for a very interesting presentation, Jinrong. I was wondering how do you attach the lignin coating to the membrane? And what kind of material is the base for the membrane? Looking forward to know how the characterization of those membranes goes 🙂
Mariona Battestini Vives
A: live answered
–
Q: Jinrong, thank you for a nice presentation. Do you observe any aggregation of the lignin-particles?
Eva Malmström Jonsson
A: Thank you Eva for your question! Yeah from the SEM we can see some aggregation of lignin particles however the mambrane itself is very uniform and homogenous.
Yes I saw from the SEM that you have aggregation. However, do you know if you nanoparticles dispersed within the film or are they mainly aggregated? Best wishes Eva
Q: ’@Liu: What advatages are we expecting from using this water purification method compared with other available methods?
Basel Al-Rudainy
A: Hi Basel very good question! It is a good idea to apply the materials for water purification. We would like test the propertise and compare it with other commercial products.
–
Q: Thank you for interesting presentation. What is the potential application of the modified wood? Will you also look into tropical wood because it is more humidity there for fungi degradation?
AnhPham
A: live answered
–
Q: Dear Maria, have you considered replacing acetic anhydride and pyridine to a more «green chemicals»?
Ievgen Pylypchuk
A: Yes, that could be an option and ideas of other chemicals to use are very welcome.
–
Q: Which methods have you used for penetrating acetylate? Have you considered mechanical properties?
Atanu Kumar Das
A: We used vacuum impregnation to get the chemical into the wood structure. Mechanical properties is not a part of this particular project, but I have collageus at Structural Mechanics at Lund University who works with that in another project. Acetylation generally makes the wood more brittle.
–
Q: Thank you for a nice presentation! Have you thought about how this can affect other properties of the wood than the fungal degradation?
Amanda Mattsson
A: Acetylation does for example affect the mechacnical properties since it makes the wood more brittle. This is of course also important to consider.
–
Q: What is the latteral resolution wit the measurments?
Torbjörn Pettersson
A: live answered
Hi! The voxel resolution is 4 micrometers with the lab-based setup and 1.6 micrometers with the synchrotron setup. The samples are 3mm wide between the notches.
Q: To Sara: Is there a specific reason as to why you are using these notched specimens in your tensile tests and not a specimen with constant cross sectional area?”
Magdalena Kaplan
A: live answered
–
Q: To Sara Johansson: Really interesting work! I wonder, which fiber properties are included in micro-scale simulations? E.g. fiber wall thickness, bonding strength, various fiber stiffness depending on the specific fiber orientation and so on? Thanks
Gustav Lindberg
A: live answered
–
Q: Thank you for a nice presentation. Why was this specific model used? How would the choice of using other models influence the results?
Basel Al-Rudainy
A: live answered
–
Q: Is there any effect of adding EAA15 on the mechanical properties of CNC-EAA composite?
Atanu Kumar Das
A: live answered
–
Q: To Aleksandar, in the material at ambient conditions there will probably be a significant amount of water? Will you consider how this affects the properties?
Tobias Benselfelt
A: Thank you for the question Tobias. Yes, this is true, but the purpose of the simulations, at this point, was to see what is happening in the melt state. We can simulate and investigate how the moisture affects the interactions at ambient conditions in the next step.
–
Q: Thank you for a very nice presentation. Missed your detailed explanation to the electrostatic interactions between SO3 and COO. Can you explain a bit more in detail.
Lars Wågberg
A: Thank you for the question Lars. The interactions between SO3 and COO are mediated by the Na+ ions. We see in the simulations that Na+ ions can be found between SO3 and COO groups, Na+ is shared between the two groups. Therefore, Na+ binds the anionic groups together because otherwise they will tend to repel each other, of course.
–
Q: What is yield (%) of nanocellulose in terms of original bark?
Atanu Kumar Das
A: live answered
–
Q: Thanks Barbara for a nice presentation. The bark contains a lot of valuable chemicals, but which one do you think will the most valuable in the end, when one consider both the process costs and the price one can sell it for?
Anette Larsson
A: live answered
–
Q: Would it be possible to see the effect of changeing to Ca2+??
Lars Wågberg
A: live answered
Absolutely. We planned to do so in the next step of the study.
Q: That question was to Aleksandar
Lars Wågberg
A: live answered
–
Q: Great effort with all site-visits! Very much appreciated and well done! Thank you!
Eva Malmström Jonsson
A: live answered
–
Q: In which step would you like to set up Micro X-Ray in the process?
Atanu Kumar Das
A: live answered
–
Q: What is the precission level?
Atanu Kumar Das
A: live answered
–
Q: To Hafizur: Can XRF resolve sodium ions coordinated to carboxylic groups on the cellulose surface? Do you think it would be possible to evaluate it?”
Korneliya Gordeyeva
A: Very interesting question. I think this is possible. Actually we are investing not pure metal of Na itself. It is ionic Na+. Because we use Na2SO3 during impregnation and we try to investigate Na+ here as well. But the problem Na energy level is very lower that is hardly to see at lab setup. Sulfur is very promising. But for Na we are try trying to use Synchrotron. We are trying to improve the technique now. I hope in our lab set up it will also be possible to image of Na soon. So if I answer in this case- XRF resolve sodium ions coordinated to carboxylic groups on the cellulose surface: YES
–
Q: Thanks Barbara for a interesting presentation!
Anette Larsson
A: live answered
–
Q: what was the reason to use a lignin NPs as a support for the enzyme?”
Ievgen Pylypchuk
A: live answered
–
