Interesting question is raised because that result that what I have got. Interesting, in one side it is known that the coating of TiO2 has caused higher affinity of membrane surface. In my opinion higher affinity, more or less, means higher permeability, higher chance that more water passes the pore of membrane. But my experiment shows the opposite. I just did a simple permeability though, but I think despite of its simplicity, it offers a very powerful tool to gain some insight about what is going on after coating in terms of its ability to allow water pass through the membrane. This post is dedicated to find out is it really true that the coating of TiO2 affect the pore size of membrane surface and make it denser.
About ultrafiltration: introduction
Combine with microfiltration, ultrafiltration (UF) is a low pressure membrane. UF is usually used for potable water treatment, biological wastewater treatment and also for ultrapure water production. The latter is common method for metal or electronic industries. UF typically operates within 40-1000 kPa (5.8-145 psi) (0.4-10 bar) having molecular weight cut off (MWCO) ranging from 1 kDa to 100 kDa (kilo Dalton).
MWCO is a term used to define 90% of molecular weight of a compound can be retained by the UF. Since UF have higher pore size or MWCO than reverse osmosis (RO), it usually produce higher flux. However, since RO has denser pore size, thus the rejection is become more excellent, even a virus may be filtered out to result a high ultrapure water.
Summary of my theses
Well, as I have written several ideas in a very old posts, such as UF fractionation, TiO2 coating, photocatalysis effect to molecular weight distribution including gel filtration chromatography, now I want to summarize what I have done and brief result.
Environmental Impact Matrix
Basically interaction matrix is a two-dimensional listing, row listing and vertical listing constitutes impact interaction between each elements of characteristics and conditions of the environment and proposed actions that may affect the environment.
Check list application
I will give a very simple application of check list approach to identify the impact and gather all relevant information and value them in terms of importance and magnitude of the impacts. Suppose you are government official in your environmental agency in your city. You receive a proposed project to build a huge shopping mall in a certain area located in the center of the city, thus in a very crowded area. Identify and value the importance and magnitude of the impacts that may arise.
Gel Filtration Chromatography: procedures
Gel filtration chromatography or perhaps just gel filtration is used to separate or purify protein based on the size properties. These protein include enzyme, polysaccharides, nucleic acids and other biomolecules. There are two kinds which technique can be applied. One is for group separation, and second is for high resolution fractionation of biomolecules.
Environmental assessment and checklist methods
Okay, I have mentioned about environmental identification or inventories, let us move to the next step which is environmental assessment.
Identification elements of impacts
Brief overiew of impact assessment has been explained in previous post. As it has been mentioned, one crucial part of impact assessment is inventory. The inventory here means to identify, to note, to gather all information and factors that may be affected by proposed projects or actions.
Impact assessment: evolution and key stage
Basic overview of impact assessment has been provided from previous post. As you are probably aware, from the embrio of environmental impact assessment long time, as time runs, the implementation has evolved into something more social.
Impact assessment: general principle
Impact assessment history began at 1970, it was the President, Richard Nixon, who signed NEPA into law, establish a national policy to encourage “productive and enjoyable harmony” between people and their environment. Because of that, the Council on Environmental Quality (CEQ) was established with its main job to monitor the environmental effects of all federal activities, assists the President in evaluating environmental probles and determines solutions to these problems.