09-06-02 02:58
No 353415
Anybee seen/heard of any otc sources?
Swim utfe and saw a few old posts stating that bees werent sure, and that its not suspicious to order from a chem supply, but swim would prefer to avoid such a place if at all possible.
"All that we are is the result of all that we have thought."
-Buddha
(Hive Bee)
09-06-02 04:52
No 353438
I think it would be a very unsuspicious purchase.
As for OTC sources, I know of none.
However I have seen Ca(OH)2 at the local pharmacist. This can be heated until it decomposes to CaO and H2O. Unfortunately this requires a temp of about 550 °C.
Mountain Boy
(Newbee)
09-06-02 05:25
No 353444
Sweet M_G, maybe there's a microwave method. A plastic wrap (microwavable) covering a microwavable dish.
(Title on BackOrder)
09-06-02 15:37
No 353593
Your local hobby shop will have small containers of CaO in their chemistry supply section. I have seen it H*bbytown's and other chain hobby shops.
All paths are the same: they lead nowhere
(Greenhorn)
09-06-02 18:31
No 353650
Youcould always try a rock quarry if you have one near you.
I went into the business for the money, and the art grew out of it.-Charlie Chaplin
(Hive Bee)
09-06-02 22:50
No 353707
MICROWAVES APPLICATION IN ORGANIC SYNTHESIS. Microwave-Assisted Preparation of Diphenylamines in 'Dry Media'
http://www.unibas.ch/mdpi/ecsoc/a0031.ht
Introduction
In the past few years there has been a growing attention in the use of microwave heating in organic synthesis since the first contributions by Gedye [1] and Giguere [2] in 1986. Microwave-assisted organic synthesis have several advantages over conventional technology: remarkable decreases in the times necessary to carry out reactions (up to 3 orders of magnitude), improved isolated yields of products (when thermal decomposition is associated with the conventionally heated reactions) and, sometimes effects on chemo-, regio- and stereoselectivity, are also achieved. On the other hand, it was shown that microwaves have a specific catalytic effect, named ³microwave effect², lowering the activation energy of a reaction [3]. Other investigators have observed similar microwave effects (i.e. reduced processing temperatures and times) in glasses and polymers, and these results have created much interest and controversy in the microwave processing community [4]. At present, there is a little doubt that measured processing temperatures and times are reduced when conventional heating is replaced with microwave energy. At issue are the underlying causes/mechanisms responsible for this effect. Specifically, is there a nonthermal effect, or are the measured temperatures not representative of the true temperatures due to inaccuracies in the temperature probe or the presence of temperature gradients? As we mentioned above, the issue of microwave effects is very controversial. Unfortunately, many of the expected results from microwave processing such as rapid and uniform heating, inverse temperature profiles, and selective heating are included in the general microwave effects [5]. However, it is affirmed that only those anomalies that cannot be predicted or easily explained based on our present understanding between thermal and microwave heating should be called ³microwave effects² [6]. Enhancements in the rates of activated processes involving material transport (i.e. sintering, ion exchange, and chemical reactions) are considered microwave effects because a reduction in the activation energy appears to be required, and investigators have been unable to provide a scientific basis for this behavior. In addition to enhanced rates, differences in reaction pathways and reaction products due to microwave processing also should be considered microwave effects [7]. Enhanced rates have been attributed to poor temperature measurements in a microwave field and localized temperature variations. To date, neither has been proven to be responsible for the observed enhancements. Many of the investigations reporting enhancements in processing rates and lower processing temperatures have paid close attention to temperature measurements; sheathed thermocuples, optical fibers [8] and non-contact measurements devices have been used. However, accurate temperature measurements are difficult in the presence of thermal gradients, which most certainly occur during microwave processing of bulk samples. Therefore, more emphasis should be placed on reporting the method of temperature measurement, the accuracy, and where the measurements are made (i.e. on the sample surface or in the interior). The simplest method for conducting microwave-assisted reactions involves irradiation of reactants only, in an open container made from quartz, Teflon or ceramic material. The scope for such processes is obviously limited, because of the reduced number of suitable organic compounds. Consequently, two other solvent-free techniques have been developed: reactions on solid mineral support in Œdry media¹, and solid-liquid phase transfer catalysis. For Œdry media¹ reactions, supports such as alumina, silica, bentonite, montmorillonite clays, and zeolites, have been investigated. Although this technique seems best suited to transformations involving a single organic species (e.g. as in deprotection, rearrangement, oxidation and dehydration), condensations have also been reported [9].
it's just mediocre in it's relevance, but anywho.
M_G, Dare ya to try it!
Calcium hydroxide thermally decomposed to calcium oxide and water using a microwave assisted dry (not for long hopefully)-media.
I will try it if you don't want to, or GOD you try it since you want it. Wouldn't it bee fun? yes
A ceramic dish, covered(?) with pierced microwavable plastic wrap. Zap it for a few seconds...Take it out of your mommas oven, if it appears wet, then goodie, try for 5seconds!
Wait for one of the red guys to say its alright.
(Bear With Me)
09-08-02 12:10
No 354347
MgO can be found in health food stores.
PB
Put your left leg down - your right leg up,
Tilt your head back - let's finish the cup!
(retarded)
09-08-02 22:10
No 354524
phooey: because I assume GOD wants CaO on Lughs advice on drying denatured alc or ethanol.(Post 329294 (former_chemist: "Denatured Alcohol", Chemicals & Equipment))could be wrong..?
ceramics suppliers I searched have MgO and many other oxides but I couldnt see CaO.
(Downer Dude)
09-09-02 17:29
No 354728
The trick to this substance is to get a lot of it. This is used to cause cement or plaster to set up rapidly. Addition of a shovelfull of this can cause cement to set up in the wheel barrow before you can pour it out.
So, go to a building supply that caters to the masonry business and ask for a bag of Quicklime. They'll point you to the slaked lime, but say no, your grandfather will only use the dried lime. Rattle off about how the set times matter a lot when working with submerged masonry and that floor repairs require you to mix on site.
20 pound bag less than 25 dollars. No questions, no records, pay cash, drag it away and keep it in two closed plastic bags, one inside the other. Get ANY water in it and you have a steaming rock to deal with. Exothermic reaction with water. They'll probably have to order it and you'll wait a week. Company in California makes it.
If you try to get a couple of pounds of it, the questions will never end. Just get a big bag and throw away what you don't use.
(Stranger)
09-10-02 13:48
No 354986
I have known of a furniture restoration business which use CaO, I believe they had it out in the locked 'dry-room' and it kept the wood dry. Check it out! (this is a genuine post)
I AM A UK BEE, FEEL FREE TO COMMUNICATE REGARDING SPECIFIC UK MATTERS
(Stranger)
09-10-02 16:53
No 355066
at your locale discount (orange) garden center buy the lawn lime (about $2 for 20 pouinds) - this is CaCO3. crushed marble etc.
heating this to around 600C will release CO2 and leave CaO. trick is to allow the released gas to exit the vicinity of the lime as the reaction is reversible.
i figure a metal tube rotating with a hot fire underneath. if the rotation and angle is correct a continuous production of CaO will resultfrom the lower end. ( would include graphic but mom took away my virtual crayons!!!)
who knows I could bee wrong.